问题
I have 2 aspects that are applied on the same method. When the method executes correctly I have no problem, everything is working fine and both aspects work as expected. The problem is when the method throw an exception. In these cases, the first aspect re-throw correctly the exception, but the second aspect is generating a nullpointerexception. I was able to reproduce the problem isolating the case on a unit test in a separated project. Those are the aspects (actually I removed all the logic, at the moment they do nothing):
@Aspect
public class LogContextConstantAspect {
@Around("execution(* *(..)) && @annotation(logContextConstant)")
public Object aroundMethod(ProceedingJoinPoint joinPoint, LogContextConstant logContextConstant) throws Throwable {
try {
Object res = joinPoint.proceed();
return res;
} catch (Throwable e) {
throw e;
}
}
}
and
@Aspect
public class LogExecutionTimeAspect {
@Around("execution(* *(..)) && @annotation(logExecutionTime)")
public Object around(ProceedingJoinPoint joinPoint, LogExecutionTime logExecutionTime) throws Throwable {
try {
Object res = joinPoint.proceed();
return res;
} catch (Throwable e) {
throw e;
}
}
}
while those are the 2 custom annotation that I implemented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface LogExecutionTime {
String paramKey() default "execution_time";
}
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD, ElementType.TYPE})
@Documented
public @interface LogContextConstant {
String name();
String value();
}
then I created a simple class with the following methods
public class AspectSimple {
public int execute() {
System.out.println("ok");
return 1;
}
public int failSimple() throws CustomException {
throw new CustomException("ko");
}
@LogExecutionTime
public int failWithAspect1() throws CustomException {
throw new CustomException("ko");
}
@LogContextConstant(name="test", value = "test")
public int failWithAspect2() throws CustomException {
throw new CustomException("ko");
}
@LogExecutionTime
@LogContextConstant(name="test", value = "test")
public int executeWithAspect() {
return 1;
}
@LogExecutionTime
@LogContextConstant(name="test", value = "test")
public int failWithAspect3() throws CustomException {
throw new CustomException("ko");
}
}
and finally this unit test
public class TestSample {
static AspectSimple as = null;
@BeforeAll
public static void setup() {
as = new AspectSimple();
}
@Test
public void test1() {
int res = as.execute();
assertEquals(1, res);
}
@Test
public void test2() {
int res = as.executeWithAspect();
assertEquals(1, res);
}
@Test
public void test3() {
try {
int res = as.failSimple();
} catch (CustomException e) {
assertNotNull(e);
} catch (Exception e) {
fail();
}
}
@Test
public void test4() {
try {
int res = as.failWithAspect1();
} catch (CustomException e) {
assertNotNull(e);
} catch (Exception e) {
fail();
}
}
@Test
public void test5() {
try {
int res = as.failWithAspect2();
} catch (CustomException e) {
assertNotNull(e);
} catch (Exception e) {
fail();
}
}
@Test
public void test6() {
try {
int res = as.failWithAspect3();
} catch (CustomException e) {
assertNotNull(e);
} catch (Exception e) {
fail();
}
}
}
All tests are running correctly, only the last one (test6) fails.
the application is running on java 8, with aspectj 1.9.4 and junit 5. Here the complete pom.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>4.0.0</modelVersion>
<groupId>it.pivimarco.samples.aspects</groupId>
<artifactId>aspect-sample</artifactId>
<version>0.0.1-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-api</artifactId>
<version>5.5.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.platform</groupId>
<artifactId>junit-platform-launcher</artifactId>
<version>1.5.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.platform</groupId>
<artifactId>junit-platform-engine</artifactId>
<version>1.5.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.platform</groupId>
<artifactId>junit-platform-commons</artifactId>
<version>1.5.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-engine</artifactId>
<version>5.5.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
<version>5.5.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-params</artifactId>
<version>5.5.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjrt</artifactId>
<version>1.9.4</version>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjtools</artifactId>
<version>1.9.4</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
<configuration>
<archive>
<manifest>
<mainClass>
org.baeldung.executable.ExecutableMavenJar
</mainClass>
</manifest>
</archive>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.22.0</version>
<executions>
<execution>
<id>default-test</id>
<phase>test</phase>
<goals>
<goal>test</goal>
</goals>
<configuration>
<includes>
<include>**/Test*.java</include>
<include>**/*Test.java</include>
<include>**/*Tests.java</include>
<include>**/*TestCase.java</include>
</includes>
<properties>
<excludeTags>slow</excludeTags>
</properties>
<forkCount>1</forkCount>
<reuseForks>false</reuseForks>
</configuration>
</execution>
</executions>
<configuration>
<includes>
<include>**/Test*.java</include>
<include>**/*Test.java</include>
<include>**/*Tests.java</include>
<include>**/*TestCase.java</include>
</includes>
<properties>
<excludeTags>slow</excludeTags>
</properties>
<forkCount>1</forkCount>
<reuseForks>false</reuseForks>
</configuration>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<target>1.8</target>
<source>1.8</source>
<parameters>true</parameters>
</configuration>
</plugin>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>aspectj-maven-plugin</artifactId>
<version>1.11</version>
<dependencies>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjtools</artifactId>
<version>1.9.4</version>
<scope>compile</scope>
</dependency>
</dependencies>
<configuration>
<source>1.8</source>
<target>1.8</target>
<proc>none</proc>
<complianceLevel>1.8</complianceLevel>
</configuration>
</plugin>
</plugins>
</build>
</project>
If I apply just a single aspect the CustomException is throwed as aspected, but when both aspects are applied I'm getting a nullpointerexception.
I've also tried to declare the precedence of the aspects, using DeclarePrecedence annotation, but it didn't work
@DeclarePrecedence("it.pivimarco.samples.aspects.LogContextConstantAspect,it.pivimarco.samples.aspects.LogExecutionTimeAspect")
This is the stacktrace of the NPE
java.lang.NullPointerException
at it.pivimarco.samples.aspects.AspectSimple.failWithAspect3_aroundBody10(AspectSimple.java:35)
at it.pivimarco.samples.aspects.AspectSimple$AjcClosure11.run(AspectSimple.java:1)
at org.aspectj.runtime.reflect.JoinPointImpl.proceed(JoinPointImpl.java:170)
at it.pivimarco.samples.aspects.LogContextConstantAspect.aroundMethod(LogContextConstantAspect.java:18)
at it.pivimarco.samples.aspects.AspectSimple.failWithAspect3(AspectSimple.java:35)
at it.pivimarco.samples.aspects.TestSample.test6(TestSample.java:70)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
回答1:
I think you uncovered a bug in the AspectJ compiler (versions 1.9.3, 1.9.4) which does not occur in version 1.9.2, as I said in my comment. I have just created AspectJ bug ticket #552687 on your behalf. Please check there for further updates. For now you can just downgrade to 1.9.2 and continue working.
Update: AspectJ 1.9.5 with the bugfix is out. Please try again. My retest was successful.
来源：https://stackoverflow.com/questions/58626598/aspectj-exceptions-handling-on-multiple-matching-advices