springBoot常见问题
参考http://blog.csdn.net/Peng_Hong_fu/article/details/53691705
不用每个接口都加@ResponseBody就可以实现返回json数据
解决方法：
把controller上面的@controller注解换成@RestController这个。设置全局捕获异常类
场景：当接口发生错误的时候就跑到那个类里面执行对应的方法，而不会出现错误页面，更人性化。
解决方法：
1.写一个controller类，用@ControllerAdvice注解标识
2.类里加上这样一句话@ExceptionHandler(RuntimeException.class)
3.任意写一个方法就可以。
@ControllerAdvice
public class ErroController {
@ExceptionHandler(RuntimeException.class)
@ResponseBody
public Map<String,String> xx(){
HashMap<String, String> map = new HashMap<String, String>();
map.put("500","错误");
return map;
}
}设置启动main入口函数的时候扫描指定的controller类
解决方法：
在该main函数的类上面加上@ComponentScan(basePackages = "controller")这样的注解。后面是路径修改默认的端口号
在resource目录下创建application.properties文件,默认加载，无需其他配置。
写上
server.port=8888springboot和mybaties集成
application.properties
server.port=9999
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/test?useSSL=false&useUnicode=true&characterEncoding=UTF-8
spring.datasource.username=root
spring.datasource.password=rootdao
package dao;
import domian.Student;
import org.apache.ibatis.annotations.Select;
import java.util.List;
public interface PayOrderDao {
@Select("select * from student;")
public List selectPayOrder();
}
app
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.ComponentScan;
/**
* SpringBoot启动类
*
* @author Administrator
*
*/
@ComponentScan(basePackages = { "controller" ,"service"})
@MapperScan(basePackages={ "dao" })
@EnableAutoConfiguration
public class App {
public static void main(String[] args) {
SpringApplication.run(App.class, args);
}
}
springboot的定时任务
附上http://cron.qqe2.com/
package com.itmayiedu.controller;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.Scheduled;
/**
* 定时任务调度
*
* @author Administrator
*
*/
@Configuration
@EnableScheduling // 启用定时任务
public class SchedulingConfig {
int count = 0;
@Scheduled(cron = "0/1 * * * * ?") // 每20秒执行一次
public void scheduler() {
count++;
System.out.println("定时任务已经出发,这是第" + count + "次");
}
}
springboot和jpa集成，启动springboot就可以在数据库中创建表。
application.yml
spring:
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:3306/test?useSSL=false&useUnicode=true&characterEncoding=UTF-8
username: root
password: root
jpa:
hibernate:
ddl-auto: create
show-sql: truepom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0modelVersion>
<groupId>com.qytxgroupId>
<artifactId>girlartifactId>
<version>0.0.1-SNAPSHOTversion>
<packaging>jarpackaging>
<name>girlname>
<description>Demo project for Spring Bootdescription>
<parent>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-parentartifactId>
<version>1.5.9.RELEASEversion>
<relativePath/>
parent>
<properties>
<project.build.sourceEncoding>UTF-8project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8project.reporting.outputEncoding>
<java.version>1.8java.version>
properties>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-testartifactId>
<scope>testscope>
dependency>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-thymeleafartifactId>
dependency>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-data-jpaartifactId>
dependency>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-devtoolsartifactId>
<optional>trueoptional>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
dependency>
dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-maven-pluginartifactId>
<configuration>
<fork>truefork>
configuration>
plugin>
plugins>
build>
project>
实体类
注意：必须有主键id和无参构造方法
package com.qytx;
import org.springframework.stereotype.Component;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
/**
* Created by lilipo on 2018/1/28.
*/
@Component
@Entity
public class girl {
@Id
@GeneratedValue
private Integer id;
private String name;
private Integer age;
public girl() {
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
}
jpa的增删改查，超级简单，不用写一条sql语句
dao层是一个接口，需要继承JpaRepository
public interface girlDao extends JpaRepository<girl,Integer> {
}
在controller层引入就可以
查讯全部
findAll()
查询一个通过id
findOne()
保存
save()
更新（前提是设置好id）
save()
删除根据id
delete()
自定义自己的查询方法 需要在接口dao层的接口拓展，但是方法名有讲究的，比如说根据age查询
方法名为 findByAge() 才可以springboot的事物注解
在需要事物的方法上加上
@Transactuionalspringboot的————————————————aop
首先引入pom
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-aopartifactId>
dependency>写个切面类
注意表达式的写法
package com.qytx;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.springframework.stereotype.Component;
/**
* Created by lilipo on 2018/1/28.
*/
@Aspect
@Component
public class HelloAspect {
@Before("execution(public * Hello.*(..))")
public void b1(){
System.out.println("1111111111");
}
@After("execution(public * Hello.*(..))")
public void b2(){
System.out.println("2222222222");
}
}
这样写的话每个方法都要写表达式好麻烦，所以把表达式抽出来。看下面
这个和上面作用一样，只不过更加灵活
package com.qytx;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;
/**
* Created by lilipo on 2018/1/28.
*/
@Aspect
@Component
public class HelloAspect {
@Pointcut("execution(public * Hello.*(..))")
public void point(){
}
@Before("point()")
public void b1(){
System.out.println("1111111111");
}
@After("point()")
public void b2(){
System.out.println("2222222222");
}
}
日志的实现
package com.qytx;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.*;
import org.omg.CORBA.Object;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.RequestAttribute;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import javax.servlet.http.HttpServletRequest;
/**
* Created by lilipo on 2018/1/28.
*/
@Aspect
@Component
public class HelloAspect {
private final static Logger log= LoggerFactory.getLogger(HelloAspect.class);
@Pointcut("execution(public * Hello.*(..))")
public void point(){
}
//想得到方法名需要传入JoinPoint这个类
@Before("point()")
public void b1(JoinPoint joinPoint){
ServletRequestAttributes requestAttributes = (ServletRequestAttributes)RequestContextHolder.getRequestAttributes();
HttpServletRequest request = requestAttributes.getRequest();
//url
log.info("url={}",request.getRequestURL());
//method类型 get 或者 post
log.info("methodType={}",request.getMethod());
//ip
log.info("ip={}",request.getRemoteAddr());
//类方法
log.info("method={}",joinPoint.getSignature().getDeclaringTypeName()+"."+joinPoint.getSignature().getName());
//参数
log.info("args={}",joinPoint.getArgs());
}
@After("point()")
public void b2(){
log.info("啦啦啦啦啦啦");
}
/**
* 得到返回之后的数据
* @param object
*/
@AfterReturning(returning = "object", pointcut = "point()")
public void doAfterReturing(Object object){
log.info("response={}",object.toString());
}
}