AOP aspectj idea 笔记

忘是亡心i 2022-10-29 07:37 160阅读 0赞

1、 idea专业版本 （非专业版不支持aspectj）

2、创建个maven项目

加入如下依赖   plugin尤其重要 ，需要运行编译后版本，才能发现生效

<dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjrt</artifactId>
        <version>1.9.6</version>
    </dependency>
    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjtools</artifactId>
        <version>1.9.6</version>
    </dependency>

<build>
            <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <version>2.3.2</version>
                    <configuration>
                        <source>8</source>
                        <target>8</target>
                    </configuration>
                </plugin>
                <plugin>
                    <groupId>com.nickwongdev</groupId>
                    <artifactId>aspectj-maven-plugin</artifactId>
                    <version>1.12.6</version>
    
    
    
                    <configuration>
                        <complianceLevel>1.8</complianceLevel>
                        <source>1.8</source>
                    </configuration>
                    <executions>
                        <execution>
                            <goals>
                                <goal>compile</goal>
                            </goals>
                        </execution>
                    </executions>
                </plugin>
            </plugins>
        </build>

3、配置AJC编译jar

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4、 写拦截器类

@Slf4j
    @Aspect
    public class SimpleIntercept {
    
        @Pointcut("execution(public * org.simple.aop.web..*(..))")
        public void traceLogAspect() {
        }
    
        @Before(value = "traceLogAspect()")
        public void doBefore() {
            System.out.println("-------------before");
        }
    
        @Around(value = "traceLogAspect()")
        public Object doAround(ProceedingJoinPoint pjp) {
            System.out.println("-------------doAround--start");
            Object ob = null;
            try {
                //请求埋点
                ob = pjp.proceed();
                //成功埋点
            } catch (Throwable e) {
                e.printStackTrace();
            }
            System.out.println("-------------doAround--end");
            return ob;
    
        }
        @AfterReturning(returning = "obj", pointcut = "traceLogAspect()")
        public void doAfterReturning(Object obj) {
            System.out.println("-------------doAfterReturning");
        }
    
        @AfterThrowing(throwing = "ex"  ,pointcut = "traceLogAspect()")
        public void AfterThrowing(Throwable ex) {
            System.out.println("-------------AfterThrowing");
        }
        @After(value = "traceLogAspect()")
        public void doAfter() {
            System.out.println("-------------doAfter");
        }
    
    }

5、写业务类

public class SimpleWepApp {
    
        public String simple() {
            return this.getClass().getName();
        }
    
    
    }

6、写启动类

public class Application {
        public static void main(String[] args) {
    
            SimpleWepApp app = new SimpleWepApp();
            String simple = app.simple();
            System.out.println(simple);
    
        }
    }

7、 编译当前应用，并运行启动函数

最终AOP --aspectj的执行顺序如下

-------------before
    -------------doAround--start
    -------------doAround--end
    -------------doAfterReturning
    -------------doAfter
    org.simple.aop.web.SimpleWepApp

8、懵逼问题

1、业务类抛异常case    并且支持顺序存在差异    另外AfterThrowing 并没有生效（最终解决之后发现完全是大意了）

-------------before
    -------------doAround--start
    java.lang.RuntimeException
    	at org.simple.aop.web.SimpleWepApp.simple_aroundBody0(SimpleWepApp.java:8)
    	at org.simple.aop.web.SimpleWepApp.simple_aroundBody1$advice(SimpleWepApp.java:27)
    	at org.simple.aop.web.SimpleWepApp.simple(SimpleWepApp.java:8)
    	at org.simple.aop.Application.main(Application.java:9)
    -------------doAround--end
    -------------doAfterReturning
    -------------doAfter
    null

-------------before
    -------------doAround--start
    -------------doAround--end
    -------------doAfterReturning
    -------------doAfter
    null
    java.lang.RuntimeException
    	at org.simple.aop.web.SimpleWepApp.simple_aroundBody0(SimpleWepApp.java:8)
    	at org.simple.aop.web.SimpleWepApp.simple_aroundBody1$advice(SimpleWepApp.java:27)
    	at org.simple.aop.web.SimpleWepApp.simple(SimpleWepApp.java:8)
    	at org.simple.aop.Application.main(Application.java:9)

编译后业务代码如下  看着感觉流程很正常

public class SimpleWepApp {
        public SimpleWepApp() {
        }
    
        public String simple() {
            JoinPoint var1 = Factory.makeJP(ajc$tjp_0, this, this);
    
            String var6;
            try {
                try {
                    SimpleIntercept.aspectOf().doBefore();
                    String var2;
                    String var3 = var2 = (String)simple_aroundBody1$advice(this, var1, SimpleIntercept.aspectOf(), (ProceedingJoinPoint)var1);
                    SimpleIntercept.aspectOf().doAfterReturning(var3);
                    var6 = var2;
                } catch (Throwable var7) {
                    SimpleIntercept.aspectOf().AfterThrowing(var7);
                    throw var7;
                }
            } catch (Throwable var8) {
                SimpleIntercept.aspectOf().doAfter();
                throw var8;
            }
    
            SimpleIntercept.aspectOf().doAfter();
            return var6;
        }
    
        static {
            ajc$preClinit();
        }
    }

找到问题原因  替换如下两种case均可 around的case 把 异常处理了   导致最终没有出现异常    AfterThrowing 在around之后 导致无法触发

@Around(value = "traceLogAspect()")
        public Object doAround(ProceedingJoinPoint pjp) {
            System.out.println("-------------doAround--start");
            Object ob = null;
            try {
                //请求埋点
                ob = pjp.proceed();
                //成功埋点
            } catch (Throwable e) {
                e.printStackTrace();
            }
            System.out.println("-------------doAround--end");
            return ob;
        }
    
    
    
        @Around(value = "traceLogAspect()")
        public Object doAround(ProceedingJoinPoint pjp) throws Throwable{
            System.out.println("-------------doAround--start");
            Object ob = null;
            try {
                //请求埋点
                ob = pjp.proceed();
                //成功埋点
            } catch (Throwable e) {
                throw e;
            }
            System.out.println("-------------doAround--end");
            return ob;
        }
    
    
    
        @Around(value = "traceLogAspect()")
        public Object doAround(ProceedingJoinPoint pjp) throws Throwable {
            System.out.println("-------------doAround--start");
            Object ob = null;
    
            ob = pjp.proceed();
    
            System.out.println("-------------doAround--end");
            return ob;
        }

最终结果如下

-------------before
    -------------doAround--start
    -------------AfterThrowing
    -------------doAfter
    Exception in thread "main" java.lang.RuntimeException
    	at org.simple.aop.web.SimpleWepApp.simple_aroundBody0(SimpleWepApp.java:8)
    	at org.simple.aop.web.SimpleWepApp.simple_aroundBody1$advice(SimpleWepApp.java:25)
    	at org.simple.aop.web.SimpleWepApp.simple(SimpleWepApp.java:8)
    	at org.simple.aop.Application.main(Application.java:9)

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