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spring学习之源码分析--AbstractAutowireCapableBeanFactory

AbstractAutowireCapableBeanFactory

抽象类AbstractAutowireCapableBeanFactory继承了AbstractBeanFactory类，以及实现了AutowireCapableBeanFactory的接口。

类结构

字段

// bean的生成策略，默认CGLIB
private InstantiationStrategy instantiationStrategy = new CglibSubclassingInstantiationStrategy();
// 解析策略的方法参数
private ParameterNameDiscoverer parameterNameDiscoverer = new DefaultParameterNameDiscoverer();
// 尝试解析循环引用
private boolean allowCircularReferences = true;
// 在循环引用的情况下，是否需要注入一个原始的bean实例
private boolean allowRawInjectionDespiteWrapping = false;
// 依赖项检查和自动装配时忽略的依赖项类型
private final Set> ignoredDependencyTypes = new HashSet<>();
// 依赖项检查和自动装配时忽略的依赖项接口
private final Set> ignoredDependencyInterfaces = new HashSet<>();
// 当前正在创建的bean
private final NamedThreadLocal currentlyCreatedBean = new NamedThreadLocal<>("Currently created bean");
// beanName和FactoryBean的映射
private final ConcurrentMap factoryBeanInstanceCache = new ConcurrentHashMap<>();
// 类和候选方法映射
private final ConcurrentMap, Method[]> factoryMethodCandidateCache = new ConcurrentHashMap<>();
// 类和PropertyDescriptor的映射
private final ConcurrentMap, PropertyDescriptor[]> filteredPropertyDescriptorsCache = new ConcurrentHashMap<>();

方法解析

AbstractAutowireCapableBeanFactory

构造函数，忽略BeanNameAware、BeanFactoryAware、BeanClassLoaderAware的依赖

public AbstractAutowireCapableBeanFactory() {
    super();
    ignoreDependencyInterface(BeanNameAware.class);
    ignoreDependencyInterface(BeanFactoryAware.class);
    ignoreDependencyInterface(BeanClassLoaderAware.class);
}
public AbstractAutowireCapableBeanFactory(@Nullable BeanFactory parentBeanFactory) {
    this();
    setParentBeanFactory(parentBeanFactory);
}

setInstantiationStrategy

getInstantiationStrategy

生成策略的设值与获取

public void setInstantiationStrategy(InstantiationStrategy instantiationStrategy) {
    this.instantiationStrategy = instantiationStrategy;
}
protected InstantiationStrategy getInstantiationStrategy() {
    return this.instantiationStrategy;
}

setParameterNameDiscoverer

getParameterNameDiscoverer

解析策略的方法参数的设值与获取

public void setParameterNameDiscoverer(@Nullable ParameterNameDiscoverer parameterNameDiscoverer) {
    this.parameterNameDiscoverer = parameterNameDiscoverer;
}
protected ParameterNameDiscoverer getParameterNameDiscoverer() {
    return this.parameterNameDiscoverer;
}

setAllowCircularReferences

尝试解析循环引用

public void setAllowCircularReferences(boolean allowCircularReferences) {
    this.allowCircularReferences = allowCircularReferences;
}

setAllowRawInjectionDespiteWrapping

在循环引用的情况下，是否需要注入一个原始的bean实例

public void setAllowRawInjectionDespiteWrapping(boolean allowRawInjectionDespiteWrapping) {
    this.allowRawInjectionDespiteWrapping = allowRawInjectionDespiteWrapping;
}

ignoreDependencyType

依赖项检查和自动装配时忽略的依赖项类型

public void ignoreDependencyType(Class type) {
    this.ignoredDependencyTypes.add(type);
}

ignoreDependencyInterface

依赖项检查和自动装配时忽略的依赖项接口

public void ignoreDependencyInterface(Class ifc) {
    this.ignoredDependencyInterfaces.add(ifc);
}

copyConfigurationFrom

除了复制父类的几种配置，好包括了instantiationStrategy、allowCircularReferences、ignoredDependencyTypes、ignoredDependencyInterfaces

public void copyConfigurationFrom(ConfigurableBeanFactory otherFactory) {
    super.copyConfigurationFrom(otherFactory);
    if (otherFactory instanceof AbstractAutowireCapableBeanFactory) {
        AbstractAutowireCapableBeanFactory otherAutowireFactory =
                (AbstractAutowireCapableBeanFactory) otherFactory;
        this.instantiationStrategy = otherAutowireFactory.instantiationStrategy;
        this.allowCircularReferences = otherAutowireFactory.allowCircularReferences;
        this.ignoredDependencyTypes.addAll(otherAutowireFactory.ignoredDependencyTypes);
        this.ignoredDependencyInterfaces.addAll(otherAutowireFactory.ignoredDependencyInterfaces);
    }
}

createBean

创建bean

public  T createBean(Class beanClass) throws BeansException {
    // Use prototype bean definition, to avoid registering bean as dependent bean.
    // 封装到BeanDefinition
    RootBeanDefinition bd = new RootBeanDefinition(beanClass);
    bd.setScope(SCOPE_PROTOTYPE);
    // 是否允许缓存
    bd.allowCaching = ClassUtils.isCacheSafe(beanClass, getBeanClassLoader());
    return (T) createBean(beanClass.getName(), bd, null);
}
protected Object createBean(String beanName, RootBeanDefinition mbd, @Nullable Object[] args)
            throws BeanCreationException {

    if (logger.isTraceEnabled()) {
        logger.trace("Creating instance of bean '" + beanName + "'");
    }
    RootBeanDefinition mbdToUse = mbd;

    // Make sure bean class is actually resolved at this point, and
    // clone the bean definition in case of a dynamically resolved Class
    // which cannot be stored in the shared merged bean definition.
    // 解析class
    Class resolvedClass = resolveBeanClass(mbd, beanName);
    if (resolvedClass != null && !mbd.hasBeanClass() && mbd.getBeanClassName() != null) {
        // 不为空，且mbd没有类信息，重新设值
        mbdToUse = new RootBeanDefinition(mbd);
        mbdToUse.setBeanClass(resolvedClass);
    }

    // Prepare method overrides.
    try {
        // 之前的lookup注解或者 标签就是这里实现的，还有
        mbdToUse.prepareMethodOverrides();
    }
    catch (BeanDefinitionValidationException ex) {
        throw new BeanDefinitionStoreException(mbdToUse.getResourceDescription(),
                beanName, "Validation of method overrides failed", ex);
    }

    try {
        // Give BeanPostProcessors a chance to return a proxy instead of the target bean instance.
        // 前置处理器是否返回bean
        Object bean = resolveBeforeInstantiation(beanName, mbdToUse);
        if (bean != null) {
            return bean;
        }
    }
    catch (Throwable ex) {
        throw new BeanCreationException(mbdToUse.getResourceDescription(), beanName,
                "BeanPostProcessor before instantiation of bean failed", ex);
    }

    try {
        // 创建bean
        Object beanInstance = doCreateBean(beanName, mbdToUse, args);
        if (logger.isTraceEnabled()) {
            logger.trace("Finished creating instance of bean '" + beanName + "'");
        }
        return beanInstance;
    }
    catch (BeanCreationException | ImplicitlyAppearedSingletonException ex) {
        // A previously detected exception with proper bean creation context already,
        // or illegal singleton state to be communicated up to DefaultSingletonBeanRegistry.
        throw ex;
    }
    catch (Throwable ex) {
        throw new BeanCreationException(
                mbdToUse.getResourceDescription(), beanName, "Unexpected exception during bean creation", ex);
    }
}
protected Object doCreateBean(final String beanName, final RootBeanDefinition mbd, final @Nullable Object[] args)
            throws BeanCreationException {

    // Instantiate the bean.
    BeanWrapper instanceWrapper = null;
    if (mbd.isSingleton()) {
        instanceWrapper = this.factoryBeanInstanceCache.remove(beanName);
    }
    if (instanceWrapper == null) {
        // 返回空，说明不是FactoryBean
        instanceWrapper = createBeanInstance(beanName, mbd, args);
    }
    // 获取bean的实例
    final Object bean = instanceWrapper.getWrappedInstance();
    // 获取bean的类型
    Class beanType = instanceWrapper.getWrappedClass();
    if (beanType != NullBean.class) {
        mbd.resolvedTargetType = beanType;
    }

    // Allow post-processors to modify the merged bean definition.
    // 后置处理器修改合并bean的定义
    synchronized (mbd.postProcessingLock) {
        if (!mbd.postProcessed) {
            try {
                applyMergedBeanDefinitionPostProcessors(mbd, beanType, beanName);
            }
            catch (Throwable ex) {
                throw new BeanCreationException(mbd.getResourceDescription(), beanName,
                        "Post-processing of merged bean definition failed", ex);
            }
            mbd.postProcessed = true;
        }
    }

    // Eagerly cache singletons to be able to resolve circular references
    // even when triggered by lifecycle interfaces like BeanFactoryAware.
    // 循环依赖
    boolean earlySingletonExposure = (mbd.isSingleton() && this.allowCircularReferences &&
            isSingletonCurrentlyInCreation(beanName));
    if (earlySingletonExposure) {
        if (logger.isTraceEnabled()) {
            logger.trace("Eagerly caching bean '" + beanName +
                    "' to allow for resolving potential circular references");
        }
        addSingletonFactory(beanName, () -> getEarlyBeanReference(beanName, mbd, bean));
    }

    // Initialize the bean instance.
    Object exposedObject = bean;
    try {
        // 实例化后，对bean进行赋值
        populateBean(beanName, mbd, instanceWrapper);
        // 赋值后，调用init方法，InitializingBean这些
        exposedObject = initializeBean(beanName, exposedObject, mbd);
    }
    catch (Throwable ex) {
        if (ex instanceof BeanCreationException && beanName.equals(((BeanCreationException) ex).getBeanName())) {
            throw (BeanCreationException) ex;
        }
        else {
            throw new BeanCreationException(
                    mbd.getResourceDescription(), beanName, "Initialization of bean failed", ex);
        }
    }

    if (earlySingletonExposure) {
        Object earlySingletonReference = getSingleton(beanName, false);
        if (earlySingletonReference != null) {
            if (exposedObject == bean) {
                exposedObject = earlySingletonReference;
            }
            else if (!this.allowRawInjectionDespiteWrapping && hasDependentBean(beanName)) {
                String[] dependentBeans = getDependentBeans(beanName);
                Set actualDependentBeans = new LinkedHashSet<>(dependentBeans.length);
                for (String dependentBean : dependentBeans) {
                    if (!removeSingletonIfCreatedForTypeCheckOnly(dependentBean)) {
                        actualDependentBeans.add(dependentBean);
                    }
                }
                if (!actualDependentBeans.isEmpty()) {
                    throw new BeanCurrentlyInCreationException(beanName,
                            "Bean with name '" + beanName + "' has been injected into other beans [" +
                            StringUtils.collectionToCommaDelimitedString(actualDependentBeans) +
                            "] in its raw version as part of a circular reference, but has eventually been " +
                            "wrapped. This means that said other beans do not use the final version of the " +
                            "bean. This is often the result of over-eager type matching - consider using " +
                            "'getBeanNamesOfType' with the 'allowEagerInit' flag turned off, for example.");
                }
            }
        }
    }

    // Register bean as disposable.
    try {
        registerDisposableBeanIfNecessary(beanName, bean, mbd);
    }
    catch (BeanDefinitionValidationException ex) {
        throw new BeanCreationException(
                mbd.getResourceDescription(), beanName, "Invalid destruction signature", ex);
    }

    return exposedObject;
}

autowireBean

给bean的属性赋值

public void autowireBean(Object existingBean) {
    // Use non-singleton bean definition, to avoid registering bean as dependent bean.
    RootBeanDefinition bd = new RootBeanDefinition(ClassUtils.getUserClass(existingBean));
    bd.setScope(BeanDefinition.SCOPE_PROTOTYPE);
    bd.allowCaching = ClassUtils.isCacheSafe(bd.getBeanClass(), getBeanClassLoader());
    BeanWrapper bw = new BeanWrapperImpl(existingBean);
    // 初始化BeanWrapper
    initBeanWrapper(bw);
    // 给bean的属性赋值
    populateBean(bd.getBeanClass().getName(), bd, bw);
}

configureBean

public Object configureBean(Object existingBean, String beanName) throws BeansException {
    // 如果已经创建了，bean的定义要清除
    markBeanAsCreated(beanName);
    // 重新设置bean的定义
    BeanDefinition mbd = getMergedBeanDefinition(beanName);
    RootBeanDefinition bd = null;
    if (mbd instanceof RootBeanDefinition) {
        RootBeanDefinition rbd = (RootBeanDefinition) mbd;
        bd = (rbd.isPrototype() ? rbd : rbd.cloneBeanDefinition());
    }
    if (bd == null) {
        bd = new RootBeanDefinition(mbd);
    }
    if (!bd.isPrototype()) {
        bd.setScope(BeanDefinition.SCOPE_PROTOTYPE);
        bd.allowCaching = ClassUtils.isCacheSafe(ClassUtils.getUserClass(existingBean), getBeanClassLoader());
    }
    BeanWrapper bw = new BeanWrapperImpl(existingBean);
    // 初始化BeanWrapper
    initBeanWrapper(bw);
    // 给bean的属性赋值
    populateBean(beanName, bd, bw);
    // 调用init方法，InitializingBean这些
    return initializeBean(beanName, existingBean, bd);
}

autowire

使用指定的自动装配策略实例化给定类的新bean实例

public Object autowire(Class beanClass, int autowireMode, boolean dependencyCheck) throws BeansException {
    // Use non-singleton bean definition, to avoid registering bean as dependent bean.
    final RootBeanDefinition bd = new RootBeanDefinition(beanClass, autowireMode, dependencyCheck);
    bd.setScope(BeanDefinition.SCOPE_PROTOTYPE);
    // 如果是构造器注入
    if (bd.getResolvedAutowireMode() == AUTOWIRE_CONSTRUCTOR) {
        return autowireConstructor(beanClass.getName(), bd, null, null).getWrappedInstance();
    }
    else {
        Object bean;
        final BeanFactory parent = this;
        if (System.getSecurityManager() != null) {
            bean = AccessController.doPrivileged((PrivilegedAction) () ->
                    getInstantiationStrategy().instantiate(bd, null, parent),
                    getAccessControlContext());
        }
        else {
            // 生成bean
            bean = getInstantiationStrategy().instantiate(bd, null, parent);
        }
        // 给bean的属性赋值
        populateBean(beanClass.getName(), bd, new BeanWrapperImpl(bean));
        return bean;
    }
} 
 
autowireBeanProperties
 
 
根据名称或类型自动装配给定bean实例的bean属性。
 
 
public void autowireBeanProperties(Object existingBean, int autowireMode, boolean dependencyCheck)
        throws BeansException {

    if (autowireMode == AUTOWIRE_CONSTRUCTOR) {
        throw new IllegalArgumentException("AUTOWIRE_CONSTRUCTOR not supported for existing bean instance");
    }
    // Use non-singleton bean definition, to avoid registering bean as dependent bean.
    RootBeanDefinition bd =
            new RootBeanDefinition(ClassUtils.getUserClass(existingBean), autowireMode, dependencyCheck);
    bd.setScope(BeanDefinition.SCOPE_PROTOTYPE);
    BeanWrapper bw = new BeanWrapperImpl(existingBean);
    initBeanWrapper(bw);
    // 给bean的属性赋值
    populateBean(bd.getBeanClass().getName(), bd, bw);
}
 
 
applyBeanPropertyValues
 
 
将具有给定名称的bean定义的属性值应用于给定的bean实例
 
 
public void applyBeanPropertyValues(Object existingBean, String beanName) throws BeansException {
    markBeanAsCreated(beanName);
    BeanDefinition bd = getMergedBeanDefinition(beanName);
    BeanWrapper bw = new BeanWrapperImpl(existingBean);
    initBeanWrapper(bw);
    applyPropertyValues(beanName, bd, bw, bd.getPropertyValues());
}
 
 
initializeBean
 
 
public Object initializeBean(Object existingBean, String beanName) {
    return initializeBean(beanName, existingBean, null);
}
protected Object initializeBean(final String beanName, final Object bean, @Nullable RootBeanDefinition mbd) {
    if (System.getSecurityManager() != null) {
        AccessController.doPrivileged((PrivilegedAction) () -> {
            invokeAwareMethods(beanName, bean);
            return null;
        }, getAccessControlContext());
    }
    else {
        // 调用BeanNameAware、BeanClassLoaderAware、BeanFactoryAware
        invokeAwareMethods(beanName, bean);
    }

    Object wrappedBean = bean;
    if (mbd == null || !mbd.isSynthetic()) {
        // 前置处理器
        wrappedBean = applyBeanPostProcessorsBeforeInitialization(wrappedBean, beanName);
    }

    try {
        // 初始化方法
        invokeInitMethods(beanName, wrappedBean, mbd);
    }
    catch (Throwable ex) {
        throw new BeanCreationException(
                (mbd != null ? mbd.getResourceDescription() : null),
                beanName, "Invocation of init method failed", ex);
    }
    if (mbd == null || !mbd.isSynthetic()) {
        // 后置处理器
        wrappedBean = applyBeanPostProcessorsAfterInitialization(wrappedBean, beanName);
    }

    return wrappedBean;
} 
 
applyBeanPostProcessorsBeforeInitialization
 
 
前置处理器
 
 
public Object applyBeanPostProcessorsBeforeInitialization(Object existingBean, String beanName)
        throws BeansException {

    Object result = existingBean;
    // 获取BeanPostProcessor处理
    for (BeanPostProcessor processor : getBeanPostProcessors()) {
        Object current = processor.postProcessBeforeInitialization(result, beanName);
        if (current == null) {
            return result;
        }
        result = current;
    }
    return result;
}
 
 
applyBeanPostProcessorsAfterInitialization
 
 
后置处理器
 
 
public Object applyBeanPostProcessorsAfterInitialization(Object existingBean, String beanName)
        throws BeansException {

    Object result = existingBean;
    // 获取BeanPostProcessor处理
    for (BeanPostProcessor processor : getBeanPostProcessors()) {
        Object current = processor.postProcessAfterInitialization(result, beanName);
        if (current == null) {
            return result;
        }
        result = current;
    }
    return result;
}
 
 
destroyBean
 
 
销毁bean
 
 
public void destroyBean(Object existingBean) {
    new DisposableBeanAdapter(existingBean, getBeanPostProcessors(), getAccessControlContext()).destroy();
}
 
 
resolveBeanByName
 
 
解析给定bean名称的bean实例，为目标工厂方法提供依赖描述符。
 
 
public Object resolveBeanByName(String name, DependencyDescriptor descriptor) {
    InjectionPoint previousInjectionPoint = ConstructorResolver.setCurrentInjectionPoint(descriptor);
    try {
        // 获取bean
        return getBean(name, descriptor.getDependencyType());
    }
    finally {
        // 为目标工厂方法提供依赖描述符
        ConstructorResolver.setCurrentInjectionPoint(previousInjectionPoint);
    }
}
 
 
resolveDependency
 
 
根据工厂中定义的bean解析指定的依赖项。
 
 
public Object resolveDependency(DependencyDescriptor descriptor, @Nullable String requestingBeanName) throws BeansException {
    return resolveDependency(descriptor, requestingBeanName, null, null);
}
 
 
predictBeanType
 
 
预测bean类型
 
 
protected Class predictBeanType(String beanName, RootBeanDefinition mbd, Class... typesToMatch) {
    // 确定给定bean定义的目标类型。
    Class targetType = determineTargetType(beanName, mbd, typesToMatch);

    // Apply SmartInstantiationAwareBeanPostProcessors to predict the
    // eventual type after a before-instantiation shortcut.
    // 通过SmartInstantiationAwareBeanPostProcessors获取实际类型
    if (targetType != null && !mbd.isSynthetic() && hasInstantiationAwareBeanPostProcessors()) {
        for (BeanPostProcessor bp : getBeanPostProcessors()) {
            if (bp instanceof SmartInstantiationAwareBeanPostProcessor) {
                SmartInstantiationAwareBeanPostProcessor ibp = (SmartInstantiationAwareBeanPostProcessor) bp;
                Class predicted = ibp.predictBeanType(targetType, beanName);
                if (predicted != null && (typesToMatch.length != 1 || FactoryBean.class != typesToMatch[0] ||
                        FactoryBean.class.isAssignableFrom(predicted))) {
                    return predicted;
                }
            }
        }
    }
    return targetType;
}
 
 
determineTargetType
 
 
确定给定bean定义的目标类型。
 
 
protected Class determineTargetType(String beanName, RootBeanDefinition mbd, Class... typesToMatch) {
    Class targetType = mbd.getTargetType();
    if (targetType == null) {
        targetType = (mbd.getFactoryMethodName() != null ?
                getTypeForFactoryMethod(beanName, mbd, typesToMatch) :
                resolveBeanClass(mbd, beanName, typesToMatch));
        if (ObjectUtils.isEmpty(typesToMatch) || getTempClassLoader() == null) {
            mbd.resolvedTargetType = targetType;
        }
    }
    return targetType;
}
 
 
getTypeForFactoryMethod
 
 
确定基于工厂方法的给定bean定义的目标类型。只有在没有为目标bean注册单例实例时才调用
 
 
protected Class getTypeForFactoryMethod(String beanName, RootBeanDefinition mbd, Class... typesToMatch) {
    // 获取目标方法返回类型
    ResolvableType cachedReturnType = mbd.factoryMethodReturnType;
    if (cachedReturnType != null) {
        return cachedReturnType.resolve();
    }

    Class factoryClass;
    boolean isStatic = true;

    String factoryBeanName = mbd.getFactoryBeanName();
    if (factoryBeanName != null) {
        // factoryBean的情况
        if (factoryBeanName.equals(beanName)) {
            throw new BeanDefinitionStoreException(mbd.getResourceDescription(), beanName,
                    "factory-bean reference points back to the same bean definition");
        }
        // Check declared factory method return type on factory class.
        // 获取指定beanName的类型
        factoryClass = getType(factoryBeanName);
        isStatic = false;
    }
    else {
        // Check declared factory method return type on bean class.
        // 解析类名
        factoryClass = resolveBeanClass(mbd, beanName, typesToMatch);
    }

    if (factoryClass == null) {
        return null;
    }
    factoryClass = ClassUtils.getUserClass(factoryClass);

    // If all factory methods have the same return type, return that type.
    // Can't clearly figure out exact method due to type converting / autowiring!
    Class commonType = null;
    Method uniqueCandidate = null;
    // 获取构造函数的参数个数
    int minNrOfArgs =
            (mbd.hasConstructorArgumentValues() ? mbd.getConstructorArgumentValues().getArgumentCount() : 0);
    // 方法候选
    Method[] candidates = this.factoryMethodCandidateCache.computeIfAbsent(
            factoryClass, ReflectionUtils::getUniqueDeclaredMethods);
    // 有多个的情况，需要遍历查找
    for (Method candidate : candidates) {
        if (Modifier.isStatic(candidate.getModifiers()) == isStatic && mbd.isFactoryMethod(candidate) &&
                candidate.getParameterCount() >= minNrOfArgs) {
            // Declared type variables to inspect?
            if (candidate.getTypeParameters().length > 0) {
                try {
                    // Fully resolve parameter names and argument values.
                    // 解析参数名和参数值
                    Class[] paramTypes = candidate.getParameterTypes();
                    String[] paramNames = null;
                    ParameterNameDiscoverer pnd = getParameterNameDiscoverer();
                    if (pnd != null) {
                        paramNames = pnd.getParameterNames(candidate);
                    }
                    ConstructorArgumentValues cav = mbd.getConstructorArgumentValues();
                    Set usedValueHolders = new HashSet<>(paramTypes.length);
                    Object[] args = new Object[paramTypes.length];
                    for (int i = 0; i < args.length; i++) {
                        ConstructorArgumentValues.ValueHolder valueHolder = cav.getArgumentValue(
                                i, paramTypes[i], (paramNames != null ? paramNames[i] : null), usedValueHolders);
                        if (valueHolder == null) {
                            valueHolder = cav.getGenericArgumentValue(null, null, usedValueHolders);
                        }
                        if (valueHolder != null) {
                            args[i] = valueHolder.getValue();
                            usedValueHolders.add(valueHolder);
                        }
                    }
                    Class returnType = AutowireUtils.resolveReturnTypeForFactoryMethod(
                            candidate, args, getBeanClassLoader());
                    uniqueCandidate = (commonType == null && returnType == candidate.getReturnType() ?
                            candidate : null);
                    commonType = ClassUtils.determineCommonAncestor(returnType, commonType);
                    if (commonType == null) {
                        // Ambiguous return types found: return null to indicate "not determinable".
                        return null;
                    }
                }
                catch (Throwable ex) {
                    if (logger.isDebugEnabled()) {
                        logger.debug("Failed to resolve generic return type for factory method: " + ex);
                    }
                }
            }
            else {
                uniqueCandidate = (commonType == null ? candidate : null);
                commonType = ClassUtils.determineCommonAncestor(candidate.getReturnType(), commonType);
                if (commonType == null) {
                    // Ambiguous return types found: return null to indicate "not determinable".
                    return null;
                }
            }
        }
    }

    mbd.factoryMethodToIntrospect = uniqueCandidate;
    if (commonType == null) {
        return null;
    }
    // Common return type found: all factory methods return same type. For a non-parameterized
    // unique candidate, cache the full type declaration context of the target factory method.
    cachedReturnType = (uniqueCandidate != null ?
            ResolvableType.forMethodReturnType(uniqueCandidate) : ResolvableType.forClass(commonType));
    mbd.factoryMethodReturnType = cachedReturnType;
    return cachedReturnType.resolve();
}
 
 
getTypeForFactoryBean
 
 
获取FactoryBean的类型
 
 
protected Class getTypeForFactoryBean(String beanName, RootBeanDefinition mbd) {
    if (mbd.getInstanceSupplier() != null) {
        ResolvableType targetType = mbd.targetType;
        if (targetType != null) {
            Class result = targetType.as(FactoryBean.class).getGeneric().resolve();
            if (result != null) {
                // 如果是FactoryBean就返回
                return result;
            }
        }
        if (mbd.hasBeanClass()) {
            Class result = GenericTypeResolver.resolveTypeArgument(mbd.getBeanClass(), FactoryBean.class);
            if (result != null) {
                return result;
            }
        }
    }

    String factoryBeanName = mbd.getFactoryBeanName();
    String factoryMethodName = mbd.getFactoryMethodName();

    if (factoryBeanName != null) {
        if (factoryMethodName != null) {
            // Try to obtain the FactoryBean's object type from its factory method declaration
            // without instantiating the containing bean at all.
            // 从声明中获取FactoryBean的对象类型
            BeanDefinition fbDef = getBeanDefinition(factoryBeanName);
            if (fbDef instanceof AbstractBeanDefinition) {
                AbstractBeanDefinition afbDef = (AbstractBeanDefinition) fbDef;
                if (afbDef.hasBeanClass()) {
                    Class result = getTypeForFactoryBeanFromMethod(afbDef.getBeanClass(), factoryMethodName);
                    if (result != null) {
                        return result;
                    }
                }
            }
        }
        // If not resolvable above and the referenced factory bean doesn't exist yet,
        // exit here - we don't want to force the creation of another bean just to
        // obtain a FactoryBean's object type...
        // 定义中没有，且没有创建过返回空
        if (!isBeanEligibleForMetadataCaching(factoryBeanName)) {
            return null;
        }
    }

    // Let's obtain a shortcut instance for an early getObjectType() call...
    // 如果是单例的，通过单例类型的方法获取FactoryBean，如果是多例的，通过多例类型的方法获取FactoryBean
    FactoryBean fb = (mbd.isSingleton() ?
            getSingletonFactoryBeanForTypeCheck(beanName, mbd) :
            getNonSingletonFactoryBeanForTypeCheck(beanName, mbd));

    if (fb != null) {
        // Try to obtain the FactoryBean's object type from this early stage of the instance.
        // 已经有FactoryBean实例，调用他的getObjectType方法
        Class result = getTypeForFactoryBean(fb);
        if (result != null) {
            return result;
        }
        else {
            // No type found for shortcut FactoryBean instance:
            // fall back to full creation of the FactoryBean instance.
            // 没有获取到通过beanName和定义获取FactoryBean的类型
            return super.getTypeForFactoryBean(beanName, mbd);
        }
    }

    if (factoryBeanName == null && mbd.hasBeanClass()) {
        // No early bean instantiation possible: determine FactoryBean's type from
        // static factory method signature or from class inheritance hierarchy...
        if (factoryMethodName != null) {
            return getTypeForFactoryBeanFromMethod(mbd.getBeanClass(), factoryMethodName);
        }
        else {
            return GenericTypeResolver.resolveTypeArgument(mbd.getBeanClass(), FactoryBean.class);
        }
    }

    return null;
}
 
 
getTypeForFactoryBeanFromMethod
 
 
查询FactoryBean的通用参数元数据(如果存在的话)以确定对象类型
 
 
private Class getTypeForFactoryBeanFromMethod(Class beanClass, final String factoryMethodName) {

    /**
     * Holder used to keep a reference to a {@code Class} value.
     */
    class Holder {

        @Nullable
        Class value = null;
    }

    final Holder objectType = new Holder();

    // CGLIB subclass methods hide generic parameters; look at the original user class.
    Class fbClass = ClassUtils.getUserClass(beanClass);

    // Find the given factory method, taking into account that in the case of
    // @Bean methods, there may be parameters present.
    ReflectionUtils.doWithMethods(fbClass, method -> {
        if (method.getName().equals(factoryMethodName) &&
                FactoryBean.class.isAssignableFrom(method.getReturnType())) {
            Class currentType = GenericTypeResolver.resolveReturnTypeArgument(method, FactoryBean.class);
            if (currentType != null) {
                objectType.value = ClassUtils.determineCommonAncestor(currentType, objectType.value);
            }
        }
    });

    return (objectType.value != null && Object.class != objectType.value ? objectType.value : null);
}
 
 
getEarlyBeanReference
 
 
获取指定bean的早期访问引用，通常用于解析循环引用。
 
 
protected Object getEarlyBeanReference(String beanName, RootBeanDefinition mbd, Object bean) {
    Object exposedObject = bean;
    if (!mbd.isSynthetic() && hasInstantiationAwareBeanPostProcessors()) {
        for (BeanPostProcessor bp : getBeanPostProcessors()) {
            if (bp instanceof SmartInstantiationAwareBeanPostProcessor) {
                SmartInstantiationAwareBeanPostProcessor ibp = (SmartInstantiationAwareBeanPostProcessor) bp;
                exposedObject = ibp.getEarlyBeanReference(exposedObject, beanName);
            }
        }
    }
    return exposedObject;
}
 
 
getSingletonFactoryBeanForTypeCheck
 
 
单例的话，获取FactoryBean
 
 
private FactoryBean getSingletonFactoryBeanForTypeCheck(String beanName, RootBeanDefinition mbd) {
    // 加锁
    synchronized (getSingletonMutex()) {
        // 是否已经实例化
        BeanWrapper bw = this.factoryBeanInstanceCache.get(beanName);
        if (bw != null) {
            // 实例化直接返回
            return (FactoryBean) bw.getWrappedInstance();
        }
        // factoryBeanInstanceCache没有，看看是否已经创建
        Object beanInstance = getSingleton(beanName, false);
        // 创建好的单例是FactoryBean，直接返回
        if (beanInstance instanceof FactoryBean) {
            return (FactoryBean) beanInstance;
        }
        // 创建好的单例不是FactoryBean，或者已经创建或者正在创建，返回空
        if (isSingletonCurrentlyInCreation(beanName) ||
                (mbd.getFactoryBeanName() != null && isSingletonCurrentlyInCreation(mbd.getFactoryBeanName()))) {
            return null;
        }
        // 
        Object instance;
        try {
            // Mark this bean as currently in creation, even if just partially.
            // 创建前检查
            beforeSingletonCreation(beanName);
            // Give BeanPostProcessors a chance to return a proxy instead of the target bean instance.
            // 看看代理能不能返回一个实例
            instance = resolveBeforeInstantiation(beanName, mbd);
            if (instance == null) {
                // 代理没返回，就创建一个
                bw = createBeanInstance(beanName, mbd, null);
                instance = bw.getWrappedInstance();
            }
        }
        catch (UnsatisfiedDependencyException ex) {
            // Don't swallow, probably misconfiguration...
            throw ex;
        }
        catch (BeanCreationException ex) {
            // Instantiation failure, maybe too early...
            if (logger.isDebugEnabled()) {
                logger.debug("Bean creation exception on singleton FactoryBean type check: " + ex);
            }
            onSuppressedException(ex);
            return null;
        }
        finally {
            // Finished partial creation of this bean.
            // 创建后检查
            afterSingletonCreation(beanName);
        }
        // 获取到的实例转换为FactoryBean
        FactoryBean fb = getFactoryBean(beanName, instance);
        if (bw != null) {
            // 放入缓存
            this.factoryBeanInstanceCache.put(beanName, bw);
        }
        return fb;
    }
}
 
 
getNonSingletonFactoryBeanForTypeCheck
 
 
不是单例的话，获取FactoryBean，比单例少的步骤是factoryBeanInstanceCache缓冲的操作
 
 
private FactoryBean getNonSingletonFactoryBeanForTypeCheck(String beanName, RootBeanDefinition mbd) {
    // 当前线程有在创建
    if (isPrototypeCurrentlyInCreation(beanName)) {
        return null;
    }

    Object instance;
    try {
        // Mark this bean as currently in creation, even if just partially.
        // 标记正在创建
        beforePrototypeCreation(beanName);
        // Give BeanPostProcessors a chance to return a proxy instead of the target bean instance.
        // 看看代理能不能返回一个实例
        instance = resolveBeforeInstantiation(beanName, mbd);
        if (instance == null) {
            BeanWrapper bw = createBeanInstance(beanName, mbd, null);
            instance = bw.getWrappedInstance();
        }
    }
    catch (UnsatisfiedDependencyException ex) {
        // Don't swallow, probably misconfiguration...
        throw ex;
    }
    catch (BeanCreationException ex) {
        // Instantiation failure, maybe too early...
        if (logger.isDebugEnabled()) {
            logger.debug("Bean creation exception on non-singleton FactoryBean type check: " + ex);
        }
        onSuppressedException(ex);
        return null;
    }
    finally {
        // Finished partial creation of this bean.
        // 标记创建结束
        afterPrototypeCreation(beanName);
    }
    // 直接转换为FactoryBean
    return getFactoryBean(beanName, instance);
}
 
 
applyMergedBeanDefinitionPostProcessors
 
 
MergedBeanDefinitionPostProcessor的合并定义
 
 
protected void applyMergedBeanDefinitionPostProcessors(RootBeanDefinition mbd, Class beanType, String beanName) {
    for (BeanPostProcessor bp : getBeanPostProcessors()) {
        if (bp instanceof MergedBeanDefinitionPostProcessor) {
            MergedBeanDefinitionPostProcessor bdp = (MergedBeanDefinitionPostProcessor) bp;
            bdp.postProcessMergedBeanDefinition(mbd, beanType, beanName);
        }
    }
}
 
 
resolveBeforeInstantiation
 
 
应用实例化前后处理程序，解决指定bean是否有实例化前快捷方式
 
 
protected Object resolveBeforeInstantiation(String beanName, RootBeanDefinition mbd) {
    Object bean = null;
    // 没有明确标明false
    if (!Boolean.FALSE.equals(mbd.beforeInstantiationResolved)) {
        // Make sure bean class is actually resolved at this point.
        if (!mbd.isSynthetic() && hasInstantiationAwareBeanPostProcessors()) {
            Class targetType = determineTargetType(beanName, mbd);
            if (targetType != null) {
                // 尝试初始化
                bean = applyBeanPostProcessorsBeforeInstantiation(targetType, beanName);
                if (bean != null) {
                    bean = applyBeanPostProcessorsAfterInitialization(bean, beanName);
                }
            }
        }
        mbd.beforeInstantiationResolved = (bean != null);
    }
    return bean;
}
 
 
applyBeanPostProcessorsBeforeInstantiation
 
 
尝试初始化
 
 
@Nullable
protected Object applyBeanPostProcessorsBeforeInstantiation(Class beanClass, String beanName) {
    for (BeanPostProcessor bp : getBeanPostProcessors()) {
        if (bp instanceof InstantiationAwareBeanPostProcessor) {
            InstantiationAwareBeanPostProcessor ibp = (InstantiationAwareBeanPostProcessor) bp;
            Object result = ibp.postProcessBeforeInstantiation(beanClass, beanName);
            if (result != null) {
                return result;
            }
        }
    }
    return null;
}
 
 
createBeanInstance
 
 
protected BeanWrapper createBeanInstance(String beanName, RootBeanDefinition mbd, @Nullable Object[] args) {
    // Make sure bean class is actually resolved at this point.
    // 解析beanClass
    Class beanClass = resolveBeanClass(mbd, beanName);

    // 判断是否有类的访问权限
    if (beanClass != null && !Modifier.isPublic(beanClass.getModifiers()) && !mbd.isNonPublicAccessAllowed()) {
        throw new BeanCreationException(mbd.getResourceDescription(), beanName,
                "Bean class isn't public, and non-public access not allowed: " + beanClass.getName());
    }

    // 是否有其他回调
    Supplier instanceSupplier = mbd.getInstanceSupplier();
    if (instanceSupplier != null) {
        return obtainFromSupplier(instanceSupplier, beanName);
    }

    // 是否有工厂方法回调
    if (mbd.getFactoryMethodName() != null) {
        return instantiateUsingFactoryMethod(beanName, mbd, args);
    }

    // Shortcut when re-creating the same bean...
    // 是否解析过
    boolean resolved = false;
    // 为false说明无参，true有参
    boolean autowireNecessary = false;
    if (args == null) {
        synchronized (mbd.constructorArgumentLock) {
            if (mbd.resolvedConstructorOrFactoryMethod != null) {
                resolved = true;
                autowireNecessary = mbd.constructorArgumentsResolved;
            }
        }
    }
    if (resolved) {
        if (autowireNecessary) {
            // 构造器注入
            return autowireConstructor(beanName, mbd, null, null);
        }
        else {
            // 无参构造
            return instantiateBean(beanName, mbd);
        }
    }

    // Candidate constructors for autowiring?
    Constructor[] ctors = determineConstructorsFromBeanPostProcessors(beanClass, beanName);
    if (ctors != null || mbd.getResolvedAutowireMode() == AUTOWIRE_CONSTRUCTOR ||
            mbd.hasConstructorArgumentValues() || !ObjectUtils.isEmpty(args)) {
        // 构造器注入
        return autowireConstructor(beanName, mbd, ctors, args);
    }

    // Preferred constructors for default construction?
    ctors = mbd.getPreferredConstructors();
    if (ctors != null) {
        // 构造器注入
        return autowireConstructor(beanName, mbd, ctors, null);
    }

    // No special handling: simply use no-arg constructor.
    // 无参构造
    return instantiateBean(beanName, mbd);
}
 
 
obtainFromSupplier
 
 
从Supplier获取bean
 
 
protected BeanWrapper obtainFromSupplier(Supplier instanceSupplier, String beanName) {
    Object instance;
    // 获取原先创建的beanName
    String outerBean = this.currentlyCreatedBean.get();
    // 用当前的替换
    this.currentlyCreatedBean.set(beanName);
    try {
        // 调用Supplier的方法
        instance = instanceSupplier.get();
    }
    finally {
        // 原先的bean存在，设置为原先的
        if (outerBean != null) {
            this.currentlyCreatedBean.set(outerBean);
        }
        // 原先的不存在，就移除，反正原本也为空
        else {
            this.currentlyCreatedBean.remove();
        }
    }
    // 没有创建对象，默认为NullBean
    if (instance == null) {
        instance = new NullBean();
    }
    // 初始化BeanWrapper并返回
    BeanWrapper bw = new BeanWrapperImpl(instance);
    initBeanWrapper(bw);
    return bw;
}
 
 
getObjectForBeanInstance
 
 
protected Object getObjectForBeanInstance(
        Object beanInstance, String name, String beanName, @Nullable RootBeanDefinition mbd) {
    // 注册当前创建的bean和给定beanName的依赖
    String currentlyCreatedBean = this.currentlyCreatedBean.get();
    if (currentlyCreatedBean != null) {
        registerDependentBean(beanName, currentlyCreatedBean);
    }
    // 返回一个bean
    return super.getObjectForBeanInstance(beanInstance, name, beanName, mbd);
}
 
 
determineConstructorsFromBeanPostProcessors
 
 
确定bean的构造函数
 
 
protected Constructor[] determineConstructorsFromBeanPostProcessors(@Nullable Class beanClass, String beanName)
        throws BeansException {

    if (beanClass != null && hasInstantiationAwareBeanPostProcessors()) {
        for (BeanPostProcessor bp : getBeanPostProcessors()) {
            if (bp instanceof SmartInstantiationAwareBeanPostProcessor) {
                // 从SmartInstantiationAwareBeanPostProcessor判断
                SmartInstantiationAwareBeanPostProcessor ibp = (SmartInstantiationAwareBeanPostProcessor) bp;
                Constructor[] ctors = ibp.determineCandidateConstructors(beanClass, beanName);
                if (ctors != null) {
                    return ctors;
                }
            }
        }
    }
    return null;
}
 
 
instantiateBean
 
 
无参构造bean
 
 
protected BeanWrapper instantiateBean(final String beanName, final RootBeanDefinition mbd) {
    try {
        Object beanInstance;
        final BeanFactory parent = this;
        if (System.getSecurityManager() != null) {
            beanInstance = AccessController.doPrivileged((PrivilegedAction) () ->
                    getInstantiationStrategy().instantiate(mbd, beanName, parent),
                    getAccessControlContext());
        }
        else {
            // 创建一个bean
            beanInstance = getInstantiationStrategy().instantiate(mbd, beanName, parent);
        }
        // 初始化BeanWrapper并返回
        BeanWrapper bw = new BeanWrapperImpl(beanInstance);
        initBeanWrapper(bw);
        return bw;
    }
    catch (Throwable ex) {
        throw new BeanCreationException(
                mbd.getResourceDescription(), beanName, "Instantiation of bean failed", ex);
    }
} 
 
instantiateUsingFactoryMethod
 
 
使用FactoryMethod实例化一个bean
 
 
protected BeanWrapper instantiateUsingFactoryMethod(
        String beanName, RootBeanDefinition mbd, @Nullable Object[] explicitArgs) {

    return new ConstructorResolver(this).instantiateUsingFactoryMethod(beanName, mbd, explicitArgs);
}
 
 
autowireConstructor
 
 
实例化后封装成BeanWrapper
 
 
protected BeanWrapper autowireConstructor(
        String beanName, RootBeanDefinition mbd, @Nullable Constructor[] ctors, @Nullable Object[] explicitArgs) {

    return new ConstructorResolver(this).autowireConstructor(beanName, mbd, ctors, explicitArgs);
}
 
 
populateBean
 
 
protected void populateBean(String beanName, RootBeanDefinition mbd, @Nullable BeanWrapper bw) {  
    if (bw == null) {
        // 如果BeanWrapper为空，但是有属性值，就跑异常
        if (mbd.hasPropertyValues()) {
            throw new BeanCreationException(
                    mbd.getResourceDescription(), beanName, "Cannot apply property values to null instance");
        }
        else {
            // Skip property population phase for null instance.
            return;
        }
    }

    // Give any InstantiationAwareBeanPostProcessors the opportunity to modify the
    // state of the bean before properties are set. This can be used, for example,
    // to support styles of field injection.
    // 看看InstantiationAwareBeanPostProcessors是否有注入值，如果有注入，就不继续注入，直接返回
    boolean continueWithPropertyPopulation = true;

    if (!mbd.isSynthetic() && hasInstantiationAwareBeanPostProcessors()) {
        for (BeanPostProcessor bp : getBeanPostProcessors()) {
            if (bp instanceof InstantiationAwareBeanPostProcessor) {
                InstantiationAwareBeanPostProcessor ibp = (InstantiationAwareBeanPostProcessor) bp;
                if (!ibp.postProcessAfterInstantiation(bw.getWrappedInstance(), beanName)) {
                    continueWithPropertyPopulation = false;
                    break;
                }
            }
        }
    }

    if (!continueWithPropertyPopulation) {
        return;
    }

    PropertyValues pvs = (mbd.hasPropertyValues() ? mbd.getPropertyValues() : null);

    if (mbd.getResolvedAutowireMode() == AUTOWIRE_BY_NAME || mbd.getResolvedAutowireMode() == AUTOWIRE_BY_TYPE) {
        // 拷贝配置信息
        MutablePropertyValues newPvs = new MutablePropertyValues(pvs);
        // Add property values based on autowire by name if applicable.
        // 根据名称注入
        if (mbd.getResolvedAutowireMode() == AUTOWIRE_BY_NAME) {
            autowireByName(beanName, mbd, bw, newPvs);
        }
        // Add property values based on autowire by type if applicable.
        // 根据类型注入
        if (mbd.getResolvedAutowireMode() == AUTOWIRE_BY_TYPE) {
            autowireByType(beanName, mbd, bw, newPvs);
        }
        pvs = newPvs;
    }
    // r容器是否有InstantiationAwareBeanPostProcessors
    boolean hasInstAwareBpps = hasInstantiationAwareBeanPostProcessors();
    // 是否进行依赖检查
    boolean needsDepCheck = (mbd.getDependencyCheck() != AbstractBeanDefinition.DEPENDENCY_CHECK_NONE);

    PropertyDescriptor[] filteredPds = null;
    if (hasInstAwareBpps) {
        if (pvs == null) {
            pvs = mbd.getPropertyValues();
        }
        // 后置处理
        for (BeanPostProcessor bp : getBeanPostProcessors()) {
            if (bp instanceof InstantiationAwareBeanPostProcessor) {
                InstantiationAwareBeanPostProcessor ibp = (InstantiationAwareBeanPostProcessor) bp;
                PropertyValues pvsToUse = ibp.postProcessProperties(pvs, bw.getWrappedInstance(), beanName);
                if (pvsToUse == null) {
                    if (filteredPds == null) {
                        filteredPds = filterPropertyDescriptorsForDependencyCheck(bw, mbd.allowCaching);
                    }
                    pvsToUse = ibp.postProcessPropertyValues(pvs, filteredPds, bw.getWrappedInstance(), beanName);
                    if (pvsToUse == null) {
                        return;
                    }
                }
                pvs = pvsToUse;
            }
        }
    }
    if (needsDepCheck) {
        if (filteredPds == null) {
            // 过滤出需要依赖检查的属性
            filteredPds = filterPropertyDescriptorsForDependencyCheck(bw, mbd.allowCaching);
        }
        // 检查依赖关系，保证依赖项已初始化
        checkDependencies(beanName, mbd, filteredPds, pvs);
    }

    if (pvs != null) {
        // 此时才开始赋值
        applyPropertyValues(beanName, mbd, bw, pvs);
    }
}
 
 
autowireByName
 
 
根据名称注入
 
 
protected void autowireByName(
        String beanName, AbstractBeanDefinition mbd, BeanWrapper bw, MutablePropertyValues pvs) {
    // 获取可set的属性，且这个属性不是简单的属性，比如基本类型、包装类这些
    String[] propertyNames = unsatisfiedNonSimpleProperties(mbd, bw);
    for (String propertyName : propertyNames) {
        // 是否有这个bean
        if (containsBean(propertyName)) {
            // 有的话获取
            Object bean = getBean(propertyName);
            // 添加到pvs
            pvs.add(propertyName, bean);
            // 注册依赖关系
            registerDependentBean(propertyName, beanName);
            if (logger.isTraceEnabled()) {
                logger.trace("Added autowiring by name from bean name '" + beanName +
                        "' via property '" + propertyName + "' to bean named '" + propertyName + "'");
            }
        }
        else {
            if (logger.isTraceEnabled()) {
                logger.trace("Not autowiring property '" + propertyName + "' of bean '" + beanName +
                        "' by name: no matching bean found");
            }
        }
    }
}
 
 
autowireByType
 
 
根据类型注入
 
 
protected void autowireByType(
        String beanName, AbstractBeanDefinition mbd, BeanWrapper bw, MutablePropertyValues pvs) {
    // 类型转换器获取
    TypeConverter converter = getCustomTypeConverter();
    if (converter == null) {
        converter = bw;
    }

    Set autowiredBeanNames = new LinkedHashSet<>(4);
     // 获取可set的属性，且这个属性不是简单的属性，比如基本类型、包装类这些
    String[] propertyNames = unsatisfiedNonSimpleProperties(mbd, bw);
    for (String propertyName : propertyNames) {
        try {
            PropertyDescriptor pd = bw.getPropertyDescriptor(propertyName);
            // Don't try autowiring by type for type Object: never makes sense,
            // even if it technically is a unsatisfied, non-simple property.
            // 如果是Object，就不管了
            if (Object.class != pd.getPropertyType()) {
                // 获取写参数
                MethodParameter methodParam = BeanUtils.getWriteMethodParameter(pd);
                // Do not allow eager init for type matching in case of a prioritized post-processor.
                // 是否立即初始化
                boolean eager = !PriorityOrdered.class.isInstance(bw.getWrappedInstance());
                // 依赖描述
                DependencyDescriptor desc = new AutowireByTypeDependencyDescriptor(methodParam, eager);
                // 解析依赖
                Object autowiredArgument = resolveDependency(desc, beanName, autowiredBeanNames, converter);
                if (autowiredArgument != null) {
                    pvs.add(propertyName, autowiredArgument);
                }
                for (String autowiredBeanName : autowiredBeanNames) {
                    // 注册依赖
                    registerDependentBean(autowiredBeanName, beanName);
                    if (logger.isTraceEnabled()) {
                        logger.trace("Autowiring by type from bean name '" + beanName + "' via property '" +
                                propertyName + "' to bean named '" + autowiredBeanName + "'");
                    }
                }
                autowiredBeanNames.clear();
            }
        }
        catch (BeansException ex) {
            throw new UnsatisfiedDependencyException(mbd.getResourceDescription(), beanName, propertyName, ex);
        }
    }
}
 
 
unsatisfiedNonSimpleProperties
 
 
返回一个不是简单的bean属性数组不包括基本类型或字符串等简单属性。
 
 
protected String[] unsatisfiedNonSimpleProperties(AbstractBeanDefinition mbd, BeanWrapper bw) {
    Set result = new TreeSet<>();
    PropertyValues pvs = mbd.getPropertyValues();
    PropertyDescriptor[] pds = bw.getPropertyDescriptors();
    for (PropertyDescriptor pd : pds) {
        if (pd.getWriteMethod() != null && !isExcludedFromDependencyCheck(pd) && !pvs.contains(pd.getName()) &&
                !BeanUtils.isSimpleProperty(pd.getPropertyType())) {
            result.add(pd.getName());
        }
    }
    return StringUtils.toStringArray(result);
}
 
 
filterPropertyDescriptorsForDependencyCheck
 
 
过滤出需要依赖检查的属性
 
 
protected PropertyDescriptor[] filterPropertyDescriptorsForDependencyCheck(BeanWrapper bw, boolean cache) {
    PropertyDescriptor[] filtered = this.filteredPropertyDescriptorsCache.get(bw.getWrappedClass());
    if (filtered == null) {
        filtered = filterPropertyDescriptorsForDependencyCheck(bw);
        // 缓存
        if (cache) {
            PropertyDescriptor[] existing =
                    this.filteredPropertyDescriptorsCache.putIfAbsent(bw.getWrappedClass(), filtered);
            if (existing != null) {
                filtered = existing;
            }
        }
    }
    return filtered;
}
protected PropertyDescriptor[] filterPropertyDescriptorsForDependencyCheck(BeanWrapper bw) {
    List pds = new ArrayList<>(Arrays.asList(bw.getPropertyDescriptors()));
    pds.removeIf(this::isExcludedFromDependencyCheck);
    return pds.toArray(new PropertyDescriptor[0]);
}
 
 
isExcludedFromDependencyCheck
 
 
指定的bean属性是否被排除在依赖项检查之外。
 
 
protected boolean isExcludedFromDependencyCheck(PropertyDescriptor pd) {
    return (AutowireUtils.isExcludedFromDependencyCheck(pd) ||
            this.ignoredDependencyTypes.contains(pd.getPropertyType()) ||
            AutowireUtils.isSetterDefinedInInterface(pd, this.ignoredDependencyInterfaces));
}
 
 
checkDependencies
 
 
检查依赖项是否是公开的
 
 
protected void checkDependencies(
        String beanName, AbstractBeanDefinition mbd, PropertyDescriptor[] pds, @Nullable PropertyValues pvs)
        throws UnsatisfiedDependencyException {

    int dependencyCheck = mbd.getDependencyCheck();
    for (PropertyDescriptor pd : pds) {
        if (pd.getWriteMethod() != null && (pvs == null || !pvs.contains(pd.getName()))) {
            boolean isSimple = BeanUtils.isSimpleProperty(pd.getPropertyType());
            boolean unsatisfied = (dependencyCheck == AbstractBeanDefinition.DEPENDENCY_CHECK_ALL) ||
                    (isSimple && dependencyCheck == AbstractBeanDefinition.DEPENDENCY_CHECK_SIMPLE) ||
                    (!isSimple && dependencyCheck == AbstractBeanDefinition.DEPENDENCY_CHECK_OBJECTS);
            if (unsatisfied) {
                throw new UnsatisfiedDependencyException(mbd.getResourceDescription(), beanName, pd.getName(),
                        "Set this property value or disable dependency checking for this bean.");
            }
        }
    }
}
 
 
applyPropertyValues
 
 
protected void applyPropertyValues(String beanName, BeanDefinition mbd, BeanWrapper bw, PropertyValues pvs) {
    // 为空直接返回
    if (pvs.isEmpty()) {
        return;
    }

    if (System.getSecurityManager() != null && bw instanceof BeanWrapperImpl) {
        ((BeanWrapperImpl) bw).setSecurityContext(getAccessControlContext());
    }

    MutablePropertyValues mpvs = null;
    List original;

    if (pvs instanceof MutablePropertyValues) {
        mpvs = (MutablePropertyValues) pvs;
        if (mpvs.isConverted()) {
            // Shortcut: use the pre-converted values as-is.
            try {
                // 已完成，直接返回
                bw.setPropertyValues(mpvs);
                return;
            }
            catch (BeansException ex) {
                throw new BeanCreationException(
                        mbd.getResourceDescription(), beanName, "Error setting property values", ex);
            }
        }
        original = mpvs.getPropertyValueList();
    }
    else {
        original = Arrays.asList(pvs.getPropertyValues());
    }

    TypeConverter converter = getCustomTypeConverter();
    if (converter == null) {
        converter = bw;
    }
    // bean定义解析器
    BeanDefinitionValueResolver valueResolver = new BeanDefinitionValueResolver(this, beanName, mbd, converter);

    // Create a deep copy, resolving any references for values.
    List deepCopy = new ArrayList<>(original.size());
    boolean resolveNecessary = false;
    // 对original的深度复制，已解析的直接加到deepCopy，没解析的先解析，再加入到deepCopy
    for (PropertyValue pv : original) {
        // 已解析
        if (pv.isConverted()) {
            deepCopy.add(pv);
        }
        else {
            String propertyName = pv.getName();
            Object originalValue = pv.getValue();
            // 解析值
            Object resolvedValue = valueResolver.resolveValueIfNecessary(pv, originalValue);
            Object convertedValue = resolvedValue;
            boolean convertible = bw.isWritableProperty(propertyName) &&
                    !PropertyAccessorUtils.isNestedOrIndexedProperty(propertyName);
            // 是否需要转换
            if (convertible) {
                // 尝试转换
                convertedValue = convertForProperty(resolvedValue, propertyName, bw, converter);
            }
            // Possibly store converted value in merged bean definition,
            // in order to avoid re-conversion for every created bean instance.
            // 解析值和原值一样
            if (resolvedValue == originalValue) {
                // 避免重复转换
                if (convertible) {
                    pv.setConvertedValue(convertedValue);
                }
                deepCopy.add(pv);
            }
            else if (convertible && originalValue instanceof TypedStringValue &&
                    !((TypedStringValue) originalValue).isDynamic() &&
                    !(convertedValue instanceof Collection || ObjectUtils.isArray(convertedValue))) {
                pv.setConvertedValue(convertedValue);
                deepCopy.add(pv);
            }
            else {
                resolveNecessary = true;
                deepCopy.add(new PropertyValue(pv, convertedValue));
            }
        }
    }
    if (mpvs != null && !resolveNecessary) {
        mpvs.setConverted();
    }

    // Set our (possibly massaged) deep copy.
    try {
        // 设值
        bw.setPropertyValues(new MutablePropertyValues(deepCopy));
    }
    catch (BeansException ex) {
        throw new BeanCreationException(
                mbd.getResourceDescription(), beanName, "Error setting property values", ex);
    }
}
 
 
convertForProperty
 
 
转换值initializeBean
 
 
private Object convertForProperty(
        @Nullable Object value, String propertyName, BeanWrapper bw, TypeConverter converter) {

    if (converter instanceof BeanWrapperImpl) {
        return ((BeanWrapperImpl) converter).convertForProperty(value, propertyName);
    }
    else {
        PropertyDescriptor pd = bw.getPropertyDescriptor(propertyName);
        MethodParameter methodParam = BeanUtils.getWriteMethodParameter(pd);
        return converter.convertIfNecessary(value, pd.getPropertyType(), methodParam);
    }
}
 
 
invokeInitMethods
 
 
protected void invokeInitMethods(String beanName, final Object bean, @Nullable RootBeanDefinition mbd)
        throws Throwable {

    boolean isInitializingBean = (bean instanceof InitializingBean);
    // 如果是InitializingBean并且有afterPropertiesSet，调用afterPropertiesSet方法
    if (isInitializingBean && (mbd == null || !mbd.isExternallyManagedInitMethod("afterPropertiesSet"))) {
        if (logger.isTraceEnabled()) {
            logger.trace("Invoking afterPropertiesSet() on bean with name '" + beanName + "'");
        }
        if (System.getSecurityManager() != null) {
            try {
                AccessController.doPrivileged((PrivilegedExceptionAction) () -> {
                    ((InitializingBean) bean).afterPropertiesSet();
                    return null;
                }, getAccessControlContext());
            }
            catch (PrivilegedActionException pae) {
                throw pae.getException();
            }
        }
        else {
            ((InitializingBean) bean).afterPropertiesSet();
        }
    }
    // 如果是InitializingBean，但没有afterPropertiesSet，调用自定义的方法
    if (mbd != null && bean.getClass() != NullBean.class) {
        String initMethodName = mbd.getInitMethodName();
        if (StringUtils.hasLength(initMethodName) &&
                !(isInitializingBean && "afterPropertiesSet".equals(initMethodName)) &&
                !mbd.isExternallyManagedInitMethod(initMethodName)) {
            invokeCustomInitMethod(beanName, bean, mbd);
        }
    }
} 
 
invokeCustomInitMethod
 
 
protected void invokeCustomInitMethod(String beanName, final Object bean, RootBeanDefinition mbd)
        throws Throwable {
    // 获取初始化方法名称
    String initMethodName = mbd.getInitMethodName();
    Assert.state(initMethodName != null, "No init method set");
    // 获取初始化方法
    final Method initMethod = (mbd.isNonPublicAccessAllowed() ?
            BeanUtils.findMethod(bean.getClass(), initMethodName) :
            ClassUtils.getMethodIfAvailable(bean.getClass(), initMethodName));

    if (initMethod == null) {
        if (mbd.isEnforceInitMethod()) {
            throw new BeanDefinitionValidationException("Could not find an init method named '" +
                    initMethodName + "' on bean with name '" + beanName + "'");
        }
        else {
            if (logger.isTraceEnabled()) {
                logger.trace("No default init method named '" + initMethodName +
                        "' found on bean with name '" + beanName + "'");
            }
            // Ignore non-existent default lifecycle methods.
            return;
        }
    }

    if (logger.isTraceEnabled()) {
        logger.trace("Invoking init method  '" + initMethodName + "' on bean with name '" + beanName + "'");
    }

    if (System.getSecurityManager() != null) {
        AccessController.doPrivileged((PrivilegedAction) () -> {
            ReflectionUtils.makeAccessible(initMethod);
            return null;
        });
        try {
            AccessController.doPrivileged((PrivilegedExceptionAction) () ->
                initMethod.invoke(bean), getAccessControlContext());
        }
        catch (PrivilegedActionException pae) {
            InvocationTargetException ex = (InvocationTargetException) pae.getException();
            throw ex.getTargetException();
        }
    }
    else {
        try {
            // 给权限
            ReflectionUtils.makeAccessible(initMethod);
            // 反射
            initMethod.invoke(bean);
        }
        catch (InvocationTargetException ex) {
            throw ex.getTargetException();
        }
    }
} 
 
postProcessObjectFromFactoryBean
 
 
调用后置处理器
 
 
protected Object postProcessObjectFromFactoryBean(Object object, String beanName) {
    return applyBeanPostProcessorsAfterInitialization(object, beanName);
}
 
 
removeSingleton
 
 
移除单例，这边额外多了factoryBeanInstanceCache缓存
 
 
protected void removeSingleton(String beanName) {
    synchronized (getSingletonMutex()) {
        super.removeSingleton(beanName);
        this.factoryBeanInstanceCache.remove(beanName);
    }
}
 
 
clearSingletonCache
 
 
清空单例，这边额外多了factoryBeanInstanceCache缓存
 
 
protected void clearSingletonCache() {
    synchronized (getSingletonMutex()) {
        super.clearSingletonCache();
        this.factoryBeanInstanceCache.clear();
    }
}
 
 
getLogger
 
 
获取logger
 
 
Log getLogger() {
    return logger;
}
 

                            
                        
                    
                    
                    

                    
                    
                    

                
                

                    
                

            
        
    
    

        
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                        苹果酱0567
面试题汇总与解析springboot后端java中间件开发语言
                        
    这段时间抽空给女朋友搭建一个个人博客，想着记录一下建站的过程，就当做笔记吧。虽然复制zjblog只要一个小时就可以搞定一个网站，或者用cms系统，三四个小时就可以做出一个前后台都有的网站，而且想做成啥样也都行。但是就是要从新做，自己做的意义不一样，更何况，俺就是专门干这个的，嘿嘿嘿要做一个网站，而且从零开始，首先呢就是技术选型了，经过一番思量决定选择-SpringBoot做后端，前端使用Vue做一
    
                    
    • 
                    
  • JavaScript 中，深拷贝（Deep Copy）和浅拷贝（Shallow Copy）
                        跳房子的前端
前端面试javascript开发语言ecmascript
                        
    在JavaScript中，深拷贝（DeepCopy）和浅拷贝（ShallowCopy）是用于复制对象或数组的两种不同方法。了解它们的区别和应用场景对于避免潜在的bugs和高效地处理数据非常重要。以下是对深拷贝和浅拷贝的详细解释，包括它们的概念、用途、优缺点以及实现方式。1.浅拷贝（ShallowCopy）概念定义：浅拷贝是指创建一个新的对象或数组，其中包含了原对象或数组的基本数据类型的值和对引用数
    
                    
    • 
                    
  • JAVA·一个简单的登录窗口
                        MortalTom
java开发语言学习
                        
    文章目录概要整体架构流程技术名词解释技术细节资源概要JavaSwing是Java基础类库的一部分，主要用于开发图形用户界面（GUI）程序整体架构流程新建项目，导入sql.jar包（链接放在了文末），编译项目并运行技术名词解释一、特点丰富的组件提供了多种可视化组件，如按钮（JButton）、文本框（JTextField）、标签（JLabel）、下拉列表（JComboBox）等，可以满足不同的界面设计
    
                    
    • 
                    
  • Spring MVC 全面指南：从入门到精通的详细解析
                        一杯梅子酱
技术栈学习springmvcjava
                        
    引言：SpringMVC，作为Spring框架的一个重要模块，为构建Web应用提供了强大的功能和灵活性。无论是初学者还是有一定经验的开发者，掌握SpringMVC都将显著提升你的Web开发技能。本文旨在为初学者提供一个全面且易于理解的学习路径，通过详细的知识点分析和实际案例，帮助你快速上手SpringMVC，让学习过程既深刻又高效。一、SpringMVC简介1.1什么是SpringMVC？Spri
    
                    
    • 
                    
  • Spring Boot中实现跨域请求
                        BABA8891
springboot后端java
                        
    在SpringBoot中实现跨域请求（CORS，Cross-OriginResourceSharing）可以通过多种方式，以下是几种常见的方法：1.使用@CrossOrigin注解在SpringBoot中，你可以在控制器或者具体的请求处理方法上使用@CrossOrigin注解来允许跨域请求。在控制器上应用：importorg.springframework.web.bind.annotation.
    
                    
    • 
                    
  • WebMagic：强大的Java爬虫框架解析与实战
                        Aaron_945
Javajava爬虫开发语言
                        
    文章目录引言官网链接WebMagic原理概述基础使用1.添加依赖2.编写PageProcessor高级使用1.自定义Pipeline2.分布式抓取优点结论引言在大数据时代，网络爬虫作为数据收集的重要工具，扮演着不可或缺的角色。Java作为一门广泛使用的编程语言，在爬虫开发领域也有其独特的优势。WebMagic是一个开源的Java爬虫框架，它提供了简单灵活的API，支持多线程、分布式抓取，以及丰富的
    
                    
    • 
                    
  • 博客网站制作教程
                        2401_85194651
javamaven
                        
    首先就是技术框架：后端：Java+SpringBoot数据库：MySQL前端：Vue.js数据库连接：JPA(JavaPersistenceAPI)1.项目结构blog-app/├──backend/│├──src/main/java/com/example/blogapp/││├──BlogApplication.java││├──config/│││└──DatabaseConfig.java
    
                    
    • 
                                
  • redis学习笔记——不仅仅是存取数据
                                    Everyday都不同
returnSourceexpire/delincr/lpush数据库分区redis
                                    
    最近项目中用到比较多redis，感觉之前对它一直局限于get/set数据的层面。其实作为一个强大的NoSql数据库产品，如果好好利用它，会带来很多意想不到的效果。（因为我搞java，所以就从jedis的角度来补充一点东西吧。PS：不一定全，只是个人理解，不喜勿喷） 
  
1、关于JedisPool.returnSource(Jedis jeids) 
  
这个方法是从red
    
                                
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  • SQL性能优化-持续更新中。。。。。。
                                    atongyeye
oraclesql
                                    
    1 通过ROWID访问表--索引 
你可以采用基于ROWID的访问方式情况,提高访问表的效率, , ROWID包含了表中记录的物理位置信息..ORACLE采用索引(INDEX)实现了数据和存放数据的物理位置(ROWID)之间的联系. 通常索引提供了快速访问ROWID的方法,因此那些基于索引列的查询就可以得到性能上的提高. 
 
2 共享SQL语句--相同的sql放入缓存 
 
3 选择最有效率的表
    
                                
    • 
                                
  • [JAVA语言]JAVA虚拟机对底层硬件的操控还不完善
                                    comsci
JAVA虚拟机
                                    
     
     如果我们用汇编语言编写一个直接读写CPU寄存器的代码段，然后利用这个代码段去控制被操作系统屏蔽的硬件资源，这对于JVM虚拟机显然是不合法的，对操作系统来讲，这样也是不合法的，但是如果是一个工程项目的确需要这样做，合同已经签了，我们又不能够这样做，怎么办呢？ 那么一个精通汇编语言的那种X客，是否在这个时候就会发生某种至关重要的作用呢？ 
 
&n
    
                                
    • 
                                
  • lvs- real
                                    男人50
LVS
                                    
    #!/bin/bash 
# 
# Script to start LVS DR real server. 
# description: LVS DR real server 
# 
#.  /etc/rc.d/init.d/functions 
 
VIP=10.10.6.252 
host='/bin/hostname' 
 
case "$1" in 
sta
    
                                
    • 
                                
  • 生成公钥和私钥
                                    oloz
DSA安全加密
                                    
    package com.msserver.core.util;

import java.security.KeyPair;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.SecureRandom;

public class SecurityUtil {

    
                                
    • 
                                
  • UIView 中加入的cocos2d，背景透明
                                    374016526
cocos2dglClearColor
                                    
    要点是首先pixelFormat:kEAGLColorFormatRGBA8，必须有alpha层才能透明。然后view设置为透明glView.opaque = NO;[director setOpenGLView:glView];[self.viewController.view setBackgroundColor:[UIColor clearColor]];[self.viewControll
    
                                
    • 
                                
  • mysql常用命令
                                    香水浓
mysql
                                    
    连接数据库 
mysql -u troy -ptroy 
 
备份表 
mysqldump -u troy -ptroy mm_database mm_user_tbl > user.sql 
 
恢复表（与恢复数据库命令相同） 
mysql -u troy -ptroy mm_database < user.sql 
 
备份数据库 
mysqldump -u troy -ptroy
    
                                
    • 
                                
  • 我的架构经验系列文章 - 后端架构 - 系统层面
                                    agevs
JavaScriptjquerycsshtml5
                                    
    系统层面：
高可用性

所谓高可用性也就是通过避免单独故障加上快速故障转移实现一旦某台物理服务器出现故障能实现故障快速恢复。一般来说，可以采用两种方式，如果可以做业务可以做负载均衡则通过负载均衡实现集群，然后针对每一台服务器进行监控，一旦发生故障则从集群中移除；如果业务只能有单点入口那么可以通过实现Standby机加上虚拟IP机制，实现Active机在出现故障之后虚拟IP转移到Standby的快速
    
                                
    • 
                                
  • 利用ant进行远程tomcat部署
                                    aijuans
tomcat
                                    
    在javaEE项目中，需要将工程部署到远程服务器上，如果部署的频率比较高，手动部署的方式就比较麻烦，可以利用Ant工具实现快捷的部署。这篇博文详细介绍了ant配置的步骤（http://www.cnblogs.com/GloriousOnion/archive/2012/12/18/2822817.html），但是在tomcat7以上不适用，需要修改配置，具体如下： 
1.配置tomcat的用户角色
    
                                
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  • 获取复利总收入
                                    baalwolf
获取
                                    
           public static void main(String args[]){ 
        int money=200; 
        int year=1; 
        double rate=0.1; 
&
    
                                
    • 
                                
  • eclipse.ini解释
                                    BigBird2012
eclipse
                                    
    大多数java开发者使用的都是eclipse，今天感兴趣去eclipse官网搜了一下eclipse.ini的配置，供大家参考，我会把关键的部分给大家用中文解释一下。还是推荐有问题不会直接搜谷歌，看官方文档，这样我们会知道问题的真面目是什么，对问题也有一个全面清晰的认识。 
Overview 
1、Eclipse.ini的作用 
Eclipse startup is controlled by th
    
                                
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  • AngularJS实现分页功能
                                    bijian1013
JavaScriptAngularJS分页
                                    
            对于大多数web应用来说显示项目列表是一种很常见的任务。通常情况下，我们的数据会比较多，无法很好地显示在单个页面中。在这种情况下，我们需要把数据以页的方式来展示，同时带有转到上一页和下一页的功能。既然在整个应用中这是一种很常见的需求，那么把这一功能抽象成一个通用的、可复用的分页（Paginator）服务是很有意义的。 
  &nbs
    
                                
    • 
                                
  • [Maven学习笔记三]Maven archetype
                                    bit1129
ArcheType
                                    
    archetype的英文意思是原型，Maven archetype表示创建Maven模块的模版，比如创建web项目，创建Spring项目等等. 
  
mvn archetype提供了一种命令行交互式创建Maven项目或者模块的方式， 
  
mvn archetype 
  
1.在LearnMaven-ch03目录下，执行命令mvn archetype:gener
    
                                
    • 
                                
  • 【Java命令三】jps
                                    bit1129
Java命令
                                    
    jps很简单，用于显示当前运行的Java进程，也可以连接到远程服务器去查看 
  
[hadoop@hadoop bin]$ jps -help
usage: jps [-help]
       jps [-q] [-mlvV] [<hostid>]

Definitions:
    <hostid>:      <hostname>[:
    
                                
    • 
                                
  • ZABBIX2.2 2.4 等各版本之间的兼容性
                                    ronin47

                                    
    zabbix更新很快，从2009年到现在已经更新多个版本，为了使用更多zabbix的新特性，随之而来的便是升级版本，zabbix版本兼容性是必须优先考虑的一点 客户端AGENT兼容 
zabbix1.x到zabbix2.x的所有agent都兼容zabbix server2.4：如果你升级zabbix server，客户端是可以不做任何改变，除非你想使用agent的一些新特性。 Zabbix代理（p
    
                                
    • 
                                
  • unity 3d还是cocos2dx哪个适合游戏？
                                    brotherlamp
unity自学unity教程unity视频unity资料unity
                                    
    unity 3d还是cocos2dx哪个适合游戏？ 
问：unity 3d还是cocos2dx哪个适合游戏？ 
答：首先目前来看unity视频教程因为是3d引擎，目前对2d支持并不完善，unity 3d 目前做2d普遍两种思路，一种是正交相机，3d画面2d视角，另一种是通过一些插件，动态创建mesh来绘制图形单元目前用的较多的是2d toolkit，ex2d，smooth moves，sm2， 

    
                                
    • 
                                
  • 百度笔试题：一个已经排序好的很大的数组，现在给它划分成m段，每段长度不定，段长最长为k，然后段内打乱顺序，请设计一个算法对其进行重新排序
                                    bylijinnan
java算法面试百度招聘
                                    
    

import java.util.Arrays;

/**
 * 最早是在陈利人老师的微博看到这道题：
 * #面试题#An array with n elements which is K most sorted，就是每个element的初始位置和它最终的排序后的位置的距离不超过常数K
 * 设计一个排序算法。It should be faster than O(n*lgn)。
    
                                
    • 
                                
  • 获取checkbox复选框的值
                                    chiangfai
checkbox
                                    
    <title>CheckBox</title>
  <script type = "text/javascript">
	doGetVal: function  doGetVal()
	{
		//var fruitName = document.getElementById("apple").value;//根据
    
                                
    • 
                                
  • MySQLdb用户指南
                                    chenchao051
mysqldb
                                    
    原网页被墙，放这里备用。  MySQLdb User's Guide  
Contents 
 
 Introduction 
 Installation 
  _mysql 
   
   MySQL C API translation 
   MySQL C API function mapping 
   Some _mysql examples 
    
  MySQLdb 
   
 
    
                                
    • 
                                
  • HIVE 窗口及分析函数
                                    daizj
hive窗口函数分析函数
                                    
    窗口函数应用场景： 
（1）用于分区排序 
（2）动态Group By 
（3）Top N 
（4）累计计算 
（5）层次查询 
 
一、分析函数 
用于等级、百分点、n分片等。 
函数             说明 
RANK()     &nbs
    
                                
    • 
                                
  • PHP ZipArchive 实现压缩解压Zip文件
                                    dcj3sjt126com
PHPzip
                                    
      
PHP ZipArchive 是PHP自带的扩展类，可以轻松实现ZIP文件的压缩和解压，使用前首先要确保PHP ZIP 扩展已经开启，具体开启方法就不说了，不同的平台开启PHP扩增的方法网上都有，如有疑问欢迎交流。这里整理一下常用的示例供参考。 
一、解压缩zip文件        01   02   03   04   05   06   07   08   09   10   11   
    
                                
    • 
                                
  • 精彩英语贺词
                                    dcj3sjt126com
英语
                                    
    I'm always here  
            我会一直在这里支持你  
              &nb
    
                                
    • 
                                
  • 基于Java注解的Spring的IoC功能
                                    e200702084
javaspringbeanIOCOffice
                                    
                                    
  
    
                                
    • 
                                
  • java模拟post请求
                                    geeksun
java
                                    
    一般API接收客户端（比如网页、APP或其他应用服务）的请求，但在测试时需要模拟来自外界的请求，经探索，使用HttpComponentshttpClient可模拟Post提交请求。  此处用HttpComponents的httpclient来完成使命。   
import org.apache.http.HttpEntity ;
import org.apache.http.HttpRespon
    
                                
    • 
                                
  • Swift语法之 ---- ?和!区别
                                    hongtoushizi
?swift!
                                    
    转载自： http://blog.sina.com.cn/s/blog_71715bf80102ux3v.html 
  
Swift语言使用var定义变量，但和别的语言不同，Swift里不会自动给变量赋初始值，也就是说变量不会有默认值，所以要求使用变量之前必须要对其初始化。如果在使用变量之前不进行初始化就会报错：  
var stringValue : String 
//
    
                                
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  • centos7安装jdk1.7
                                    jisonami
jdkcentos
                                    
    安装JDK1.7 
步骤1、解压tar包在当前目录 
[root@localhost usr]#tar -xzvf jdk-7u75-linux-x64.tar.gz 
步骤2：配置环境变量 
在etc/profile文件下添加 
export JAVA_HOME=/usr/java/jdk1.7.0_75 
export CLASSPATH=/usr/java/jdk1.7.0_75/lib 

    
                                
    • 
                                
  • 数据源架构模式之数据映射器
                                    home198979
PHP架构数据映射器datamapper
                                    
    前面分别介绍了数据源架构模式之表数据入口、数据源架构模式之行和数据入口数据源架构模式之活动记录，相较于这三种数据源架构模式，数据映射器显得更加“高大上”。 
  
一、概念 
数据映射器（Data Mapper）：在保持对象和数据库（以及映射器本身）彼此独立的情况下，在二者之间移动数据的一个映射器层。概念永远都是抽象的，简单的说，数据映射器就是一个负责将数据映射到对象的类数据。 
&nb
    
                                
    • 
                                
  • 在Python中使用MYSQL
                                    pda158
mysqlpython
                                    
    缘由   　　近期在折腾一个小东西须要抓取网上的页面。然后进行解析。将结果放到 
数据库中。   　　了解到 
Python在这方面有优势，便选用之。   　　由于我有台 
server上面安装有 
mysql，自然使用之。在进行数据库的这个操作过程中遇到了不少问题，这里 
记录一下，大家共勉。   　　 
python中mysql的调用   　　 
百度之后能够通过MySQLdb进行数据库操作。
    
                                
    • 
                                
  • 单例模式
                                    hxl1988_0311
java单例设计模式单件
                                    
    package com.sosop.designpattern.singleton;

/*
 * 单件模式：保证一个类必须只有一个实例，并提供全局的访问点
 * 
 * 所以单例模式必须有私有的构造器，没有私有构造器根本不用谈单件
 * 
 * 必须考虑到并发情况下创建了多个实例对象
 * */

/**
 * 虽然有锁，但是只在第一次创建对象的时候加锁，并发时不会存在效率
    
                                
    • 
                                
  • 27种迹象显示你应该辞掉程序员的工作
                                    vipshichg
工作
                                    
    1、你仍然在等待老板在2010年答应的要提拔你的暗示。 2、你的上级近10年没有开发过任何代码。 3、老板假装懂你说的这些技术，但实际上他完全不知道你在说什么。 4、你干完的项目6个月后才部署到现场服务器上。 5、时不时的，老板在检查你刚刚完成的工作时，要求按新想法重新开发。 6、而最终这个软件只有12个用户。 7、时间全浪费在办公室政治中，而不是用在开发好的软件上。 8、部署前5分钟才开始测试。
    
                                
    •