一、环境准备
本案例使用的JDK版本是JDK1.8
二、步骤
1、新建项目
图片.png
2、输入项目名称
输入项目名称.png
3、生成项目
生成项目.jpg
4、加入maven框架支持
加入maven框架支持.jpg
5、加入aspectj的maven依赖和maven的aspectj的编译支持插件
<?xml version="1.0" encoding="UTF-8"?>
<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>4.0.0</modelVersion>
<groupId>groupId</groupId>
<artifactId>aspectj-helloworld</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.9.2</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>aspectj-maven-plugin</artifactId>
<version>1.5</version>
<configuration>
<complianceLevel>1.7</complianceLevel>
<includes>
<include>**/*.java</include>
<include>**/*.aj</include>
</includes>
<aspectDirectory>src/main/java/aspectj</aspectDirectory>
<XaddSerialVersionUID>true</XaddSerialVersionUID>
<showWeaveInfo>true</showWeaveInfo>
</configuration>
<executions>
<execution>
<id>compile_with_aspectj</id>
<goals>
<goal>compile</goal>
</goals>
</execution>
<execution>
<id>test-compile_with_aspectj</id>
<goals>
<goal>test-compile</goal>
</goals>
</execution>
</executions>
<dependencies>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjtools</artifactId>
<version>1.8.5</version>
</dependency>
</dependencies>
</plugin>
</plugins>
</build>
</project>
6、新建com.lin.aspectj.HelloAsectj.aj文件
package com.lin.aspectj;
public aspect HelloAspect {
pointcut HelloWorldPointCut() : execution(* com.lin.aspectj.*.*(..));
Object around():HelloAspect.HelloWorldPointCut(){
System.out.println("asp");
proceed();
return new Object();
}
}
7、新建com.lin.aspectj.Hello类
package com.lin.aspectj;
public class Hello {
public void test(){
System.out.println("hello world");
}
public static void main(String[] args) {
new Hello().test();
}
}
8、运行Hello类中的main方法,结果如下：
/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/bin/java -Dfile.encoding=UTF-8 -classpath /Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/lib/tools.jar:/Users/xmly/workspace/java/aspectj-helloworld/target/classes:/Users/xmly/workspace/repository/org/aspectj/aspectjweaver/1.9.2/aspectjweaver-1.9.2.jar com.lin.aspectj.Hello
asp
asp
hello world
Process finished with exit code 0
9、该项目的总体结构如下图所示：
全局.png
10、该demo项目已放在github上，有需要的同学可以上去下载
https://github.com/lwbkfc/aspectj-helloworld
11、提问：有同学能解释一下为什么asp打印了两次吗？
