Question

我试图实现自己的注释处理器，它看起来像这样：

MyProcessor.java：

package com.example.processing;

import java.util.Set;

import javax.annotation.processing.AbstractProcessor;
import javax.annotation.processing.RoundEnvironment;
import javax.annotation.processing.SupportedAnnotationTypes;
import javax.annotation.processing.SupportedSourceVersion;
import javax.lang.model.SourceVersion;
import javax.lang.model.element.TypeElement;

@SupportedAnnotationTypes({"com.example.annotations.Service", "com.example.annotations.Module"})
@SupportedSourceVersion(SourceVersion.RELEASE_6)
public class MyProcessor extends AbstractProcessor {

@Override
public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {

    //...        

    return true;

}

下面是pom：

的pom.xml：

<?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>com.example</groupId>
<artifactId>crawler</artifactId>
<version>1.0-SNAPSHOT</version>

<properties>
    <java.version>1.6</java.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>commons-lang3</artifactId>
        <version>3.3.2</version>
    </dependency>

    <dependency>
        <groupId>com.google.guava</groupId>
        <artifactId>guava</artifactId>
        <version>17.0</version>
    </dependency>

    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.11</version>
    </dependency>

    <dependency>
        <groupId>org.mockito</groupId>
        <artifactId>mockito-core</artifactId>
        <version>1.9.5</version>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <artifactId>maven-compiler-plugin</artifactId>
            <configuration>
                <compilerArgument>-proc:none</compilerArgument>
                <source>${java.version}</source>
                <target>${java.version}</target>
            </configuration>
        </plugin>
    </plugins>
</build>

</project>

在另一个应用程序中，我使用处理应用程序中定义的自定义注释 com.example.annotations.Service 和 com.example.annotations.Module 注释了一些类。。处理应用程序作为依赖性添加到另一个应用程序中。见下文：

pom.xml（在带注释的应用程序中）

...

<dependencies>
    ...
    <dependency>
         <groupId>com.example</groupId>
         <artifactId>crawler</artifactId>
         <version>1.0-SNAPSHOT</version>
         <scope>provided</scope>
    </dependecy>
    ...
</dependencies>

...

但是，当我在带注释的应用程序上尝试 mvn clean install 时（在处理应用程序上执行 mvn install 之后），我最终得到以下错误：

堆栈追踪：

org.apache.maven.BuildFailureException: Compilation failure
error: Bad service configuration file, or exception thrown while constructing Processor object: javax.annotation.processing.Processor: Provider com.example.processing.MyProcessor could not be instantiated: java.lang.NoClassDefFoundError: com.google.common.base.Predicate
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:715)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalWithLifecycle(DefaultLifecycleExecutor.java:556)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:535)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:387)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:348)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:180)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:328)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:138)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:362)
    at org.apache.maven.cli.compat.CompatibleMain.main(CompatibleMain.java:60)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:60)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37)
    at java.lang.reflect.Method.invoke(Method.java:611)
    at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)
    at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)
    at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)
    at org.codehaus.classworlds.Launcher.main(Launcher.java:375)
Caused by: org.apache.maven.plugin.CompilationFailureException:     Compilation failure
error: Bad service configuration file, or exception thrown while constructing Processor object: javax.annotation.processing.Processor: Provider com.example.processing.MyProcessor could not be instantiated: java.lang.NoClassDefFoundError: com.google.common.base.Predicate
    at org.apache.maven.plugin.AbstractCompilerMojo.execute(AbstractCompilerMojo.java:516)
    at org.apache.maven.plugin.CompilerMojo.execute(CompilerMojo.java:114)
    at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:490)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:694)
    ... 17 more

这里有什么问题。我是否需要构建我的处理应用程序jar，以便它包含所有依赖项？根据我的研究，我不应该这样做。

任何帮助将不胜感激。谢谢。

无法解析自定义注释处理器的依赖关系。 NoClassDefFoundError的

0 个答案: