Springboot学习笔记
Springboot学习笔记
1.基本配置
1.1springboot的入口类和@SpringBootApplication
POM文件配置
<parent>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-parentartifactId>
<version>1.5.10.RELEASEversion>
parent>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
dependencies>
<build>
<defaultGoal>installdefaultGoal>
<plugins>
<plugin>
<groupId>org.apache.maven.pluginsgroupId>
<artifactId>maven-compiler-pluginartifactId>
<version>3.7.0version>
<configuration>
<source>1.8source>
<target>1.8target>
configuration>
plugin>
<plugin>
<groupId>org.apache.maven.pluginsgroupId>
<artifactId>maven-resources-pluginartifactId>
<version>3.0.2version>
<configuration>
<encoding>UTF-8encoding>
configuration>
plugin>
<plugin>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-maven-pluginartifactId>
plugin>
plugins>
build>启动程序
@SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class);
}
}@SpringBootApplication是SpringBoot的核心注解，是一个组合注解，源码如下
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
@SpringBootConfiguration
@EnableAutoConfiguration
@ComponentScan(excludeFilters = {
@Filter(type = FilterType.CUSTOM, classes = TypeExcludeFilter.class),
@Filter(type = FilterType.CUSTOM, classes = AutoConfigurationExcludeFilter.class) })
public @interface SpringBootApplication {
@AliasFor(annotation = EnableAutoConfiguration.class, attribute = "exclude")
Class[] exclude() default {};
@AliasFor(annotation = EnableAutoConfiguration.class, attribute = "excludeName")
String[] excludeName() default {};
@AliasFor(annotation = ComponentScan.class, attribute = "basePackages")
String[] scanBasePackages() default {};
@AliasFor(annotation = ComponentScan.class, attribute = "basePackageClasses")
Class[] scanBasePackageClasses() default {};
}1.2 关闭特定的自动配置
关闭特定的自动配置应该使用@SpringBootApplication注解的exclude参数
例：
@SpringBootApplication(exclude = {DataSourceAutoConfiguration.class})1.3 定制Banner
在springboot启动的时候会有一个默认的启动图案
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v1.5.10.RELEASE)在src/main/resources下新建一个banner.txt，通过http://patorjk.com/software/taag网站生成字符，如敲入simba1949，将网站生成的字符复制在banner.txt中，即可定制
1.4 创建一个可执行的jar
添加打包插件
<plugin>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-maven-pluginartifactId>
plugin>命令运行：mvn package
会得到如下jar包
[INFO] Building jar: D:\Learn\IntelliJ IDEA\Workspace\springboot\springboot01\target\springboot01-1.0-SNAPSHOT.jar
在命令窗口输入下面命令即可运行：
java -jar springboot01-1.0-SNAPSHOT.jar1.5 SpringBoot的配置文件
springboot使用一个全局的配置文件application.properties或者application.yml，放置在src/main/resources目录下或者类路径/config下
读取properties文件时，需要引入依赖包
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-configuration-processorartifactId>
<optional>trueoptional>
dependency>在application.properties中添加如下数据
#配置对应的属性
user.username:simba1949
user.age:hi,${user.username}!!!@ConfigurationProperties注解读取properties配置文件,prefix=”user”
@Service
@ConfigurationProperties(prefix = "user")
public class UserServiceImpl implements UserService {
private String username;
private String say;
@Override
public void testProperties(){
System.out.println(username);
System.out.println("*******");
System.out.println(say);
}
//需要属性的settter方法
public void setUsername(String username) {
this.username = username;
}
public void setSay(String say) {
this.say = say;
}
}1.6 属性配置校验
@NotNull
private Integer age;运行时会报错
1.7 使用xml配置
@ImportResource({"classpath:ApplicationContext-tran.xml","classpath:ApplicationContext-dao.xml"})2.日志配置
在application.properties中配置日志系统
#日志配置
#日志级别
logging.level.root=DEBUG
logging.level.org.springframework.web=DEBUG
logging.level.org.hibernate=DEBUG
#输出日志名字
#logging.file=springboot001.log
#日志输出路径
logging.path=D:/logs3.Profile配置
Profile是Spring用来针对不同的环境进行不同的配置提供支持的，全局Profile配置实用application-{profile}.properties。
通过在application.properties中设置spring.profiles.active=dev指定活动的Profile。
测试：生产环境端口为80，开发环境端口为8888
生产环境（application-prod.properties）配置如下：
server.port=80开发环境（application-dev.properties）配置如下：
server.port=8888application.properties配置：
spring.profiles.active=dev运行如图
4.SpringBoot运行原理
5.http的编码配置
SpringBoot内置的自动配置功能：http的编码配置
在常规项目中配置http编码的时候在web.xml里配置一个filter
<filter>
<filter-name>encodingfilter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilterfilter-class>
<init-param>
<param-name>encodingparam-name>
<param-value>UTF-8param-value>
init-param>
<init-param>
<param-name>forceEncodingparam-name>
<param-value>trueparam-value>
init-param>
filter>
<filter-mapping>
<filter-name>encodingfilter-name>
<url-pattern>/*url-pattern>
filter-mapping>自动配置要满足俩个条件
- 能配置CharacterEncodingFilter这个Bean
- 能配置encoding和forceEncoding这俩个参数
默认编码方式为UTF-8，若修改可使用spring.http.encoding.charset=编码；
设置forceEncoding，默认为true，若修改可使用spring.http.encoding.force=false
6.SSL配置
将生成的.keystore文件复制到项目的根目录下，然后再application.properties中配饰SSL
server.ssl.key-store=mykey.keystore
server.ssl.key-password=123456
server.ssl.key-store-type=JKS
server.ssl.key-alias=tomcat
目录结构
7.SpringBoot的开发
7.1Tomcat配置
springboot默认内嵌Tomcat为servlet容器
配置servlet容器
#配置程序端口，默认为8080
server.port=
#用户会话session过期时间，以秒为单位
server.session.timeout=
#配置访问路径，默认为/
server.context-path=配置tomcat
#配置tomcat编码，默认为utf-8
server.tomcat.uri-encoding=7.2Favicon配置
springboot默认开启，关闭favicon在application.properties中配置即可
spring.mvc.favicon.enabled=false定制Favicon
需要spring.mvc.favicon.enabled开启，不配置默认开启也可，将favicon.ico(文件名不能变动过)放置在src/main/resources/static下即可，运行效果
目录结构
7.3集成springmvc
Json Rest实现
在springboot应用中，任何spring@RestController默认渲染为JSON响应
例如：
@GetMapping(value = "/list",produces = "application/json")
@ResponseBody
public List list(){
List users = new ArrayList();
users.add(new User("李白","诗仙"));
users.add(new User("杜甫","诗圣"));
users.add(new User("王维","诗佛"));
users.add(new User("白居易","诗魔"));
users.add(new User("李贺","诗鬼"));
users.add(new User("苏轼","诗神"));
return users;
} 
XML Rest实现
如果classpath下存在Jackson XML扩展（jackson-dataformat-xml） ， 它会被用来渲染XML响应， 示例和JSON的非常相似。想要使用它， 只需为你的项目添加以下的依赖
<dependency>
<groupId>com.fasterxml.jackson.dataformatgroupId>
<artifactId>jackson-dataformat-xmlartifactId>
dependency>例如：
@GetMapping(value = "/xml",produces = "application/xml")
@ResponseBody
public List xml(){
List users = new ArrayList();
users.add(new User("李 白","诗仙"));
users.add(new User("杜 甫","诗圣"));
users.add(new User("王 维","诗佛"));
users.add(new User("白居易","诗魔"));
users.add(new User("李 贺","诗鬼"));
users.add(new User("苏 轼","诗神"));
return users;
} 
SpringMVC视图解析器配置
由于springboot已经不推荐使用jsp了，如果想使用jsp，需要手动引入相关依赖包。
<dependency>
<groupId>org.apache.tomcat.embedgroupId>
<artifactId>tomcat-embed-jasperartifactId>
dependency>
<dependency>
<groupId>javax.servletgroupId>
<artifactId>javax.servlet-apiartifactId>
dependency>
<dependency>
<groupId>javax.servletgroupId>
<artifactId>jstlartifactId>
dependency>在application.properties配置视图解析器
#视图解析器
spring.mvc.view.prefix=/WEB-INF/view/
spring.mvc.view.suffix=.jsp7.4集成MyBatis
pom文件添加依赖
<dependency>
<groupId>org.mybatis.spring.bootgroupId>
<artifactId>mybatis-spring-boot-starterartifactId>
<version>1.3.1version>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<version>6.0.6version>
<scope>runtimescope>
dependency>mybatis在application.properties配置
#配置数据源
spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/test?serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=19491001
#表示打印出sql语句
logging.level.com.shyroke.mapper=debug
#mybatis配置
mybatis.mapper-locations=classpath*:top/simba1949/mapper/*Mapper.xml
mybatis.type-aliases-package=top.simba1949.entity还需要在Application配置@MapperScan(basePackages = “top.simba1949.mapper”)
@SpringBootApplication
//@mapperscan 指定被扫描的mapper所在的包路径
@MapperScan(basePackages = "top.simba1949.mapper")
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class);
}
}7.5 集成druid连接池
pom文件添加依赖
<dependency>
<groupId>com.alibabagroupId>
<artifactId>druidartifactId>
<version>1.0.20version>
dependency>在application.properties配置
#配置数据源
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/test?serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=19491001
#表示打印出sql语句
logging.level.com.shyroke.mapper=debug
# 下面为连接池的补充设置，应用到上面所有数据源中
# 初始化大小，最小，最大
spring.datasource.initialSize=5
spring.datasource.minIdle=5
spring.datasource.maxActive=207.6 声明式事务配置
7.6.1 基于注解
只需要在参与事务控制的方法上加上@Transactional注解即可。
@Transactional
@Override
public void addUser(User user) {
int acount = userMapper.addUser(user);
}7.6.2 基于xml配置文件
引入aop依赖
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-aopartifactId>
dependency>xml事务传播特性配置
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd">
<aop:config>
<aop:pointcut expression="execution(* top.simba1949.service.impl.*.*(..))" id="tranpointcut" />
<aop:advisor advice-ref="txAdvice" pointcut-ref="tranpointcut" />
aop:config>
<tx:advice id="txAdvice" transaction-manager="txManager">
<tx:attributes>
<tx:method name="add*" propagation="REQUIRED" isolation="DEFAULT"
rollback-for="java.lang.Exception" />
<tx:method name="save*" propagation="REQUIRED" isolation="DEFAULT"
rollback-for="java.lang.Exception" />
<tx:method name="insert*" propagation="REQUIRED" isolation="DEFAULT"
rollback-for="java.lang.Exception" />
<tx:method name="query*" read-only="true" />
<tx:method name="select*" read-only="true" />
<tx:method name="find*" read-only="true" />
tx:attributes>
tx:advice>
<bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource" />
bean>
beans>配置导入
@SpringBootApplication
//@mapperscan 指定被扫描的mapper所在的包路径
@MapperScan(basePackages = "top.simba1949.mapper")
//@ImportResource 导入事务配置
@ImportResource(value = "classpath:spring-aop.xml")
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class);
}
}7.7 文件上传
配置文件上传属性
#默认支持文件上传.
spring.http.multipart.enabled=true
#支持文件写入磁盘.
spring.http.multipart.file-size-threshold=0
# 最大支持文件大小
spring.http.multipart.max-file-size=1Mb
# 最大支持请求大小
spring.http.multipart.max-request-size=10Mbjava代码
@RestController
@RequestMapping(value = "/upload")
public class UploadController {
@PostMapping(value = "/image")
public String image(@RequestParam(value = "userimage")MultipartFile file, HttpSession session) throws Exception{
//获取upload目录，不存在就创建
String realPath = session.getServletContext().getRealPath("upload");
File path = new File(realPath);
if(!path.exists()){
path.mkdirs();
}
//上传
file.transferTo(new File(realPath+"/"+file.getOriginalFilename()));
return "http://localhost:8080/upload/"+file.getOriginalFilename();
}
}7.8 注册拦截器
7.8.1自定义拦截器
public class UserInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o) throws Exception {
System.out.println("preHandle-------------------------------");
return true;
}
@Override
public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
System.out.println("postHandle-------------------------------");
}
@Override
public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
System.out.println("afterCompletion-------------------------------");
}
}7.8.2 注册拦截器
@Configuration
public class WebRegister extends WebMvcConfigurerAdapter {
@Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(new UserInterceptor()).addPathPatterns("/add");
super.addInterceptors(registry);
}
}7.9 springboot异常处理
@ControllerAdvice
该注解是spring2.3以后新增的一个注解，主要是用来Controller的一些公共的需求的低侵入性增强提供辅助，作用于@RequestMapping标注的方法上。
@ExceptionHandler
该注解是配合@ControllerAdvice一起使用的注解，自定义错误处理器，可自己组装json字符串，并返回到页面。
@ControllerAdvice
public class ErrorHandlerController {
@ResponseBody
@ExceptionHandler(value = Exception.class)
public String handleGlobalException(Exception e){
System.out.println("0000000000000000000000------------------00000000000000000000000000"+e.getMessage());
return "error";
}
}