9月16日spring笔记
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AOP 通知的配置
示例
Man.java
package com.aop;
public class Man {
private String name = "大壮";
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public void qq(String toName){
if(b) {
throw new RuntimeException("聊天犯规了");
}
System.out.println(this.name + "在和[" + toName + "]聊QQ");
}
public String mm(){
System.out.println(this.name + "在聊MM");
return "很高兴";
}
}
FBI.java
package com.aop;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.Signature;
import java.util.Arrays;
public class FBI {
public void before(JoinPoint joinPoint){
Object obj = joinPoint.getTarget();
System.out.println("目标对象: "+ obj.getClass().getName());
Object[] args = joinPoint.getArgs();
System.out.println("目标对象方法参数: "+ Arrays.toString(args));
Signature signature = joinPoint.getSignature();
System.out.println("目标对象的方法: "+signature.getName());
}
public void after(JoinPoint joinPoint, Object val){
Signature signature = joinPoint.getSignature();
System.out.println("目标对象方法"+signature.getName()+"执行完毕,返回值"+ val);
}
public void throwsException(JoinPoint joinPoint, Throwable e){
Signature signature = joinPoint.getSignature();
System.out.println("目标对象方法"+signature.getName()+"异常! !, 信息: "+e.getMessage());
}
public void afterFinally(JoinPoint joinPoint){
Signature signature = joinPoint.getSignature();
System.out.println("目标对象的方法" + signature.getName() + "执行完毕");
}
// 无论有没有异常，都会执行
}
spring-aop.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 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/aop https://www.springframework.org/schema/aop/spring-aop.xsd">
<bean id="man" class="com.aop.Man"></bean>
<bean id="fbi" class="com.aop.FBI"></bean>
<aop:config>
<!-- 切面规则 执行在Man的任意方法,参数为任意-->
<aop:pointcut id="pointcut" expression="execution(* com.aop.Man.*(..))"/>
<aop:aspect ref="fbi">
<!-- fbi这个bean的before方法 :before为前置通知-->
<aop:before method="before" pointcut-ref="pointcut"></aop:before>
<aop:after-returning method="after" pointcut-ref="pointcut" returning="val"></aop:after-returning>
<!-- 注意：此处的val必须与fbi里面的Object val 参数形参名相同 -->
<aop:after-throwing method="throwsException" pointcut-ref="pointcut" throwing="e"></aop:after-throwing>
<!-- afterFinally 不管有无异常，都会执行 -->
<aop:after method="afterFinally" pointcut-ref="pointcut"></aop:after>
</aop:aspect>
</aop:config>
</beans>
TestAop.java
package com.aop;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class TestAop {
private ClassPathXmlApplicationContext ac;
@Before
public void init(){
ac = new ClassPathXmlApplicationContext("spring-aop.xml");
}
@Test
public void test(){
Man man = ac.getBean(Man.class);
man.qq("小美");
man.mm();
}
@After
public void destroy(){
ac.close();
}
}
输出结果
目标对象: com.aop.Man
目标对象方法参数: [小美]
目标对象的方法: qq
目标对象方法qq异常! !, 信息: 聊天犯规了
目标对象的方法qq执行完毕
java.lang.RuntimeException: 聊天犯规了
<!-- ...以下省略若干异常信息 -->
<!-- 如果没有异常，继续输出以下代码 -->
大壮在和[小美]聊QQ
目标对象方法qq执行完毕
目标对象: com.aop.Man
目标对象方法参数: []
目标对象的方法: mm
大壮在聊MM
目标对象方法mm执行完毕，返回值：很高兴
环绕通知
aop 配置: spring-aop.xml
<aop:around method="around" pointcut-ref="pointcut"></aop:around>
FBI.java
public Object around(ProceedingJoinPoint joinPoint){
Object result = null;
//前置通知
Object obj = joinPoint.getTarget();
System.out.println("目标对象: "+ obj.getClass().getName());
try {
//执行目标对象方法
result = joinPoint.proceed();
//返回后通知
System.out.println("result" + result);
}catch (Throwable e){
//执行异常通知
System.out.println("catch" + e.getMessage());
}finally {
//执行最终通知
System.out.println("finally");
}
return result;
}
结果：
目标对象: com.aop.Man
catch聊天犯规了
finally
目标对象: com.aop.Man
大壮在聊MM
result很高兴
finally
Process finished with exit code 0
采用注解方式配置通知
spring-auto.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop https://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">
<!-- 通过在的Spring的配置中引入下列元素来启用Spring对@AspectJ的支持-->
<aop:aspectj-autoproxy></aop:aspectj-autoproxy>
<context:component-scan base-package="com.auto"></context:component-scan>
</beans>
FBI.java
package com.auto;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import java.util.Arrays;
@Aspect
public class FBI {
@Before("execution(* com.auto.Man.*(..))")
public void before(JoinPoint joinPoint){
Object obj = joinPoint.getTarget();
System.out.println("目标对象: "+ obj.getClass().getName());
Object[] args = joinPoint.getArgs();
System.out.println("目标对象方法参数: "+ Arrays.toString(args));
Signature signature = joinPoint.getSignature();
System.out.println("目标对象的方法: "+signature.getName());
}
public void afterReturning(JoinPoint joinPoint, Object val){
Signature signature = joinPoint.getSignature();
System.out.println("目标对象方法"+signature.getName()+"执行完毕, 返回值："+val);
}
public void throwsException(JoinPoint joinPoint, Throwable e){
Signature signature = joinPoint.getSignature();
System.out.println("目标对象方法"+signature.getName()+"异常! !, 信息: "+e.getMessage());
}
public void afterFinally(JoinPoint joinPoint){
Signature signature = joinPoint.getSignature();
System.out.println("目标对象的方法" + signature.getName() + "执行完毕");
}
//环绕通知
public Object around(ProceedingJoinPoint joinPoint){
Object result = null;
//前置通知
Object obj = joinPoint.getTarget();
System.out.println("目标对象: "+ obj.getClass().getName());
try {
//执行目标对象方法
result = joinPoint.proceed();
//返回后通知
System.out.println("result" + result);
}catch (Throwable e){
//执行异常通知
System.out.println("catch" + e.getMessage());
}finally {
//执行最终通知
System.out.println("finally");
}
return result;
}
}
Man.java
package com.auto;
import org.springframework.stereotype.Component;
import java.util.Random;
@Component
public class Man {
private String name = "大壮";
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public void qq(String toName){
boolean b = new Random().nextBoolean();
if(b) {
throw new RuntimeException("聊天犯规了");
}
System.out.println(this.name + "在和[" + toName + "]聊QQ");
}
public String mm(){
System.out.println(this.name + "在聊MM");
return "很高兴";
}
}
TestAop.java
package com.auto;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class TestAop {
private ClassPathXmlApplicationContext ac;
@Test
public void test(){
Man man = ac.getBean(Man.class);
man.qq("小美");
}
@Before
public void init(){
ac = new ClassPathXmlApplicationContext("spring-auto.xml");
}
@After
public void destroy(){
ac.close();
}
}
结果
目标对象: com.auto.Man
目标对象方法参数: [小美]
目标对象的方法: qq
java.lang.RuntimeException: 聊天犯规了
对数据持久化的支持
传统的执行效率最高
Spring JDBC抽象框架由四部分组成：datasource、support、core、object
数据源：描述数据库，数据库连接池，(池化技术)
常用的数据源：DBCP, C3p0, Druid, HikariCP(光)
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