我正在用Java编写一个简单的自定义注释,但遇到了一个问题。
LogMeCustomAnnotation.java
package fun.n.learn.annotation;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
// We need this annotation only till before compilation.
@Retention(RetentionPolicy.SOURCE)
// This is a simple custom annotation.
public @interface LogMeCustomAnnotation {
}
LogMeCustomAnnotationProcessor.java
package fun.n.learn.annotation;
import java.util.Set;
import javax.annotation.processing.AbstractProcessor;
import javax.annotation.processing.Messager;
import javax.annotation.processing.RoundEnvironment;
import javax.annotation.processing.SupportedAnnotationTypes;
import javax.lang.model.element.TypeElement;
import javax.tools.Diagnostic;
// List the custom annotations that are supported.
@SupportedAnnotationTypes({ "fun.n.learn.annotation.LogMeCustomAnnotation" })
// Extend AbstractProcessor. This will let you process.
public class LogMeCustomAnnotationProcessor extends AbstractProcessor {
@Override
public boolean process(Set<? extends TypeElement> annotations,
RoundEnvironment roundEnv) {
Messager messager = processingEnv.getMessager();
messager.printMessage(Diagnostic.Kind.NOTE, "I was here.");
// TODO: Put some meaningful code here. Right now just get it to work.
// return false;
// We have already handled these annotations. No more. So return true.
return true;
}
}
/src/main/resources/META-INF/services/javax.annotation.processing.Processor
fun.n.learn.annotation.LogMeCustomAnnotationProcessor
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>fun.n.learn</groupId>
<artifactId>javaCustomAnnotation</artifactId>
<version>0.1.0</version>
<build>
<plugins>
<plugin>
<!-- Configure the project to use java 8 version. -->
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.5.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
<!-- Disable annotation processing for ourselves. -->
<!-- <compilerArgument>-proc:none</compilerArgument> -->
</configuration>
</plugin>
</plugins>
</build>
</project>
现在,当我运行mvn -e clean install
时,我会遇到以下问题
[ERROR] COMPILATION ERROR :
[INFO] -------------------------------------------------------------
[ERROR] Bad service configuration file, or exception thrown while constructing Processor object: javax.annotation.processing.Processor: Provider fun.n.learn.annotation.LogMeCustomAnnotationProcessor not found
[INFO] 1 error
我一定错过了一个简单的技巧。有什么帮助吗?
默认的maven生命周期使用javax.annotation.processing.Processor文件作为类路径的一部分来运行javac。这会导致编译器期望文件中列出的注释处理器的已编译实例。但LogMeCustomAnnotationProcessor
此时尚未编译,因此编译器会引发"错误的服务配置文件…"错误。请参阅错误报告。
为了解决这个问题,maven编译阶段可以分开,首先编译注释处理器,然后编译整个项目。
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.5.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
<executions>
<execution>
<id>default-compile</id>
<configuration>
<compilerArgument>-proc:none</compilerArgument>
<includes>
<include>fun/n/learn/annotation/LogMeCustomAnnotationProcessor.java</include>
<!--include dependencies required for LogMeCustomAnnotationProcessor -->
</includes>
</configuration>
</execution>
<execution>
<id>compile-project</id>
<phase>compile</phase>
<goals>
<goal>compile</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
default-compile
执行在禁用注释处理的情况下编译LogMeCustomAnnotationProcessor
,以便成功编译。compile-project
通过注释处理编译了整个项目。
好的。发现问题。早些时候,我的pom.xml已经注释掉了proc:none
行。现在我已经把它重新投入使用了,它正在编译得很好。我需要弄清楚这条线到底是干什么的,但我的问题的答案只是把proc:none
放回游戏中。这就是pom.xml的构建部分现在的样子。
<build>
<plugins>
<plugin>
<!-- Configure the project to use java 8 version. -->
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.5.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
<!-- Disable annotation processing for ourselves. -->
<compilerArgument>-proc:none</compilerArgument>
</configuration>
</plugin>
</plugins>
</build>
按照以下步骤解决此问题:
- 编辑
nbproject/project.properties
文件 - 搜索
javac.processorpath
,并将其更改为:
javac.processorpath=
${javac.classpath}:
${libs.eclipselink.classpath}
我遇到过这个错误,特别是
Bad service configuration file, or exception thrown while constructing Processor object: javax.annotation.processing.Processor: Provider com.iviz.schemarestriction.processor.SchemaRestrictionCompilationProcessor could not be instantiated
将maven项目从JDK 1.8(1.8.0_201)迁移到OpenJDK 11(11.0.2)时。
它是通过添加对(2.3.1是最新的稳定版本)的依赖来修复的
<dependency>
<groupId>javax.xml.bind</groupId>
<artifactId>jaxb-api</artifactId>
<version>2.3.1</version>
</dependency>
我只需删除注释处理器的Target文件夹就解决了以下问题,并重新编译了框架。它像魔术一样发挥作用。
问题:
java: Bad service configuration file, or exception thrown while constructing Processor object: javax.annotation.processing.Processor: Provider com.tracelink.automation.framework.processors.FeedFactoryProcessor not found
尝试使用以下标志编译它:-proc:none