1.业务描述
一次开发中，遇到接收多个表的数据，并批量插入数据库的需求，在此记录 代码逻辑
2.实际开发
因为涉及到的表有很多，差不多4,50个，所以考虑使用泛型和反射来简化代码，提高开发效率
2.1 接收数据bean
样例中会精简部分代码
/**
* 数据同步到保信--请求参数
* Created by Youdmeng on 2019/6/4 0004.
*/
@Data
public class SaveToBaoxin {
private String syncId;
/**
* 审核信息表
*/
@Valid
private List checkInfoEOList;
/**
* 组织机构表
*/
private List orgInfoEOList;
} 2.2 取出个属性的列表对象
使用反射依次获取每组数据，
因为每组数据的类型不尽相同，所有使用泛型T来接收
private void dataSave(SaveToBaoxin saveToBaoxin) {
List successItemEOS = new ArrayList<>();
syncDate = new Date();
Class cls = saveToBaoxin.getClass();
Field[] fields = cls.getDeclaredFields();
for (Field field : fields) {
if (StringUtils.equals(field.getName(), "syncId")) {
continue;
}
field.setAccessible(true);
Object object = ReflectionUtils.getFieldValue(saveToBaoxin, field.getName());
List list = (List) object;
save(list, successItemEOS);
}
try {
baoXinDao.insertSuccessItemList(successItemEOS);
} catch (Exception e) {
logger.error("成功数据记录存储失败", e);
//手动回滚事务
TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();
}
} 2.3 核心保存代码
private void save(List list, List successItemEOS) {
List checkInfoEOKeyList = new ArrayList<>();
String table = null;
String tableDesc = "";
String dataDesc = "";//审核信息表
for (T t : list) {
Class dataBean = t.getClass();
try {
table = SyncTableInfoEnums.getByLowerTableName(t.getClass().getSimpleName()).getTable();
tableDesc = SyncTableInfoEnums.getByLowerTableName(t.getClass().getSimpleName()).getTableDesc();
// dataDesc = t.getService() + "数据主键:" + checkInfoEO.getKeyId();
if (null == ReflectionUtils.getFieldValue(t, "id") || null == ReflectionUtils.getFieldValue(t, "systemId")) {
logger.error("|数据同步失败| " + " [" + table + "] [" + tableDesc + "] [" + dataDesc + "] [缺失数据主键]");
syncLogService.errorLog(t, table, tableDesc, dataDesc, "缺失数据主键");
} else {
ReflectionUtils.setFieldValue(t, "syncFlag", 2);
Class syncDao = Class.forName("com.adc.da.manual.dao.manage.BaoxinSyncDao");
try {
ReflectionUtils
.invokeMethod(sqlSession.getMapper(syncDao), "insert" + StringBuiltifer.formateClassName(table) + "EO", dataBean, t);
} catch (Exception e) {
if (e.getCause() instanceof DuplicateKeyException) {
logger.info("主键已存在,进行数据更新");
ReflectionUtils
.invokeMethod(
sqlSession.getMapper(syncDao),
"updateByPrimaryKey" + StringBuiltifer.formateClassName(table) + "EO",
dataBean,
t);
}else {
throw e;
}
}
}
checkInfoEOKeyList.add(ReflectionUtils.getFieldValue(t, "id") + "");
} catch (Exception e) {
logger.error("|数据同步失败| " + " [" + table + "] [" + tableDesc + "] [" + dataDesc + "] [" + e.getMessage() + "]", e);
syncLogService.errorLog(t, table, tableDesc, dataDesc, e.getMessage());
}
}
successItemEOS.add(putSuccessItem(table, checkInfoEOKeyList));
} 代码解析：
Class syncDao = Class.forName("com.adc.da.manual.dao.manage.BaoxinSyncDao") 之前的部分，是取出数据，并根据业务逻辑进行校验，
本段代码，是获取要存储数据的dao层接口
@Repository
public interface BaoxinSyncDao {
void insertcheckInfoEO(CheckInfoEO checkInfoEO);
void insertorgInfoEO (OrgInfoEO orgInfoEO);
}
核心插入代码 ：
ReflectionUtils.invokeMethod(sqlSession.getMapper(syncDao), "insert" + StringBuiltifer.formateClassName(table) + "EO", dataBean, t);本段代码等同于：
Method method = syncDao.getDeclaredMethod("insertcheckInfoEO", new Class[] { List.class });
method.invoke(sqlSession.getMapper(syncDao),t);在开发过程中，我们会遇到需要使用使用反射来规范化批量操作的情况，但是当我们直接操作对应dao时，是不对的，我们需要反射sqlSession，来获取dao层控制权
2.4 反射工具类ReflectionUtils
/**
* 反射工具类.
*
* 提供访问私有变量,获取泛型类型Class, 提取集合中元素的属性, 转换字符串到对象等Util函数.
*/
public class ReflectionUtils {
private static final Logger logger = LoggerFactory.getLogger(ReflectionUtils.class);
/**
* 调用Getter方法.
*/
public static Object invokeGetterMethod(Object obj, String propertyName) {
String getterMethodName = "get" + StringUtils.capitalize(propertyName);
return invokeMethod(obj, getterMethodName, null, new Object[] {});
}
/**
* 调用Setter方法.使用value的Class来查找Setter方法.
*/
public static void invokeSetterMethod(Object obj, String propertyName, Object value) {
invokeSetterMethod(obj, propertyName, value, null);
}
/**
* 调用Setter方法.
*
* @param propertyType 用于查找Setter方法,为空时使用value的Class替代.
*/
public static void invokeSetterMethod(Object obj, String propertyName, Object value, Class propertyType) {
Class type = propertyType != null ? propertyType : value.getClass();
String setterMethodName = "set" + StringUtils.capitalize(propertyName);
invokeMethod(obj, setterMethodName, type, new Object[] { value });
}
/**
* 直接读取对象属性值, 无视private/protected修饰符, 不经过getter函数.
*/
public static Object getFieldValue(final Object obj, final String fieldName) {
Field field = getAccessibleField(obj, fieldName);
if (field == null) {
throw new IllegalArgumentException("Could not find field [" + fieldName + "] on target [" + obj + "]");
}
Object result = null;
try {
result = field.get(obj);
} catch (IllegalAccessException e) {
logger.error("不可能抛出的异常{}", e.getMessage());
}
return result;
}
/**
* 直接设置对象属性值, 无视private/protected修饰符, 不经过setter函数.
*/
public static void setFieldValue(final Object obj, final String fieldName, final Object value) {
Field field = getAccessibleField(obj, fieldName);
if (field == null) {
throw new IllegalArgumentException("Could not find field [" + fieldName + "] on target [" + obj + "]");
}
try {
field.set(obj, value);
} catch (IllegalAccessException e) {
logger.error("不可能抛出的异常:{}", e.getMessage());
}
}
/**
* 循环向上转型, 获取对象的DeclaredField, 并强制设置为可访问.
*
* 如向上转型到Object仍无法找到, 返回null.
*/
public static Field getAccessibleField(final Object obj, final String fieldName) {
Assert.notNull(obj, "object不能为空");
Assert.hasText(fieldName, "fieldName");
for (Class superClass = obj.getClass(); superClass != Object.class; superClass = superClass.getSuperclass()) {
try {
Field field = superClass.getDeclaredField(fieldName);
field.setAccessible(true);
return field;
} catch (NoSuchFieldException e) {//NOSONAR
// Field不在当前类定义,继续向上转型
}
}
return null;
}
/**
* 直接调用对象方法, 无视private/protected修饰符.
* 用于一次性调用的情况.
*/
public static Object invokeMethod(final Object obj, final String methodName, final Class tClass, final Object args) {
Method method = getAccessibleMethod(obj, methodName, tClass);
if (method == null) {
throw new IllegalArgumentException("Could not find method [" + methodName + "] on target [" + obj + "]");
}
try {
return method.invoke(obj, args);
} catch (Exception e) {
throw convertReflectionExceptionToUnchecked(e);
}
}
/**
* 循环向上转型, 获取对象的DeclaredMethod,并强制设置为可访问.
* 如向上转型到Object仍无法找到, 返回null.
*
* 用于方法需要被多次调用的情况. 先使用本函数先取得Method,然后调用Method.invoke(Object obj, Object... args)
*/
public static Method getAccessibleMethod(final Object obj, final String methodName, final Class tClass) {
Assert.notNull(obj, "object不能为空");
for (Class superClass = obj.getClass(); superClass != Object.class; superClass = superClass.getSuperclass()) {
try {
Method method = superClass.getDeclaredMethod(methodName, new Class[] { tClass });
method.setAccessible(true);
return method;
} catch (NoSuchMethodException e) {//NOSONAR
// Method不在当前类定义,继续向上转型
}
}
return null;
}
/**
* 通过反射, 获得Class定义中声明的父类的泛型参数的类型.
* 如无法找到, 返回Object.class.
* eg.
* public UserDao extends HibernateDao
*
* @param clazz The class to introspect
* @return the first generic declaration, or Object.class if cannot be determined
*/
@SuppressWarnings({ "unchecked", "rawtypes" })
public static Class getSuperClassGenricType(final Class clazz) {
return getSuperClassGenricType(clazz, 0);
}
/**
* 通过反射, 获得Class定义中声明的父类的泛型参数的类型.
* 如无法找到, 返回Object.class.
*
* 如public UserDao extends HibernateDao
*
* @param clazz clazz The class to introspect
* @param index the Index of the generic ddeclaration,start from 0.
* @return the index generic declaration, or Object.class if cannot be determined
*/
@SuppressWarnings("rawtypes")
public static Class getSuperClassGenricType(final Class clazz, final int index) {
Type genType = clazz.getGenericSuperclass();
if (!(genType instanceof ParameterizedType)) {
logger.warn(clazz.getSimpleName() + "'s superclass not ParameterizedType");
return Object.class;
}
Type[] params = ((ParameterizedType) genType).getActualTypeArguments();
if (index >= params.length || index < 0) {
logger.warn("Index: " + index + ", Size of " + clazz.getSimpleName() + "'s Parameterized Type: "
+ params.length);
return Object.class;
}
if (!(params[index] instanceof Class)) {
logger.warn(clazz.getSimpleName() + " not set the actual class on superclass generic parameter");
return Object.class;
}
return (Class) params[index];
}
/**
* 将反射时的checked exception转换为unchecked exception.
*/
public static RuntimeException convertReflectionExceptionToUnchecked(Exception e) {
if (e instanceof IllegalAccessException || e instanceof IllegalArgumentException
|| e instanceof NoSuchMethodException) {
return new IllegalArgumentException("Reflection Exception.", e);
} else if (e instanceof InvocationTargetException) {
return new RuntimeException("Reflection Exception.", ((InvocationTargetException) e).getTargetException());
} else if (e instanceof RuntimeException) {
return (RuntimeException) e;
}
return new RuntimeException("Unexpected Checked Exception.", e);
}
}
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