'Annotation processor @autoservice
Need help with annotation processor . I have created a simple annotation processor which uses @autoservice annotation that checks whether the field which is annotated is final. But it is not showing any compile time errors. This is my configuration
Annotation:
@Retention(RetentionPolicy.SOURCE)
@Target(ElementType.FIELD)
public @interface Store {
int temp() default 0;
}
Annotation Processor:
@SupportedAnnotationTypes("com.self.Store")
@AutoService(Processor.class)
public class Process extends AbstractProcessor {
@Override
public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
for (Element element : roundEnv.getElementsAnnotatedWith(Store.class)) {
TypeElement typeElement = (TypeElement) element;
for (Element element2 : typeElement.getEnclosedElements()) {
VariableElement variableElement = (VariableElement) element2;
if (!variableElement.getModifiers().contains(Modifier.FINAL)) {
processingEnv.getMessager().printMessage(Diagnostic.Kind.ERROR, "it should be final");
}
}
}
return true;
}
}
pom file:
<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>annotations</groupId>
<artifactId>annotations</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>annotation</name>
<dependencies>
<dependency>
<groupId>com.google.auto.service</groupId>
<artifactId>auto-service</artifactId>
<version>1.0-rc2</version>
<optional>true</optional>
</dependency>
</dependencies>
<build>
<sourceDirectory>src</sourceDirectory>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.5.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
</project>
Testing file:
public class Test {
@Store
public int id;
}
Solution 1:[1]
According to the Baeldung's topic on annotation processor development, you must configure your maven compiler plugin first and declare the auto-service annotation processor there. That is the missing step. FYI, if you are using Gradle you may declare it under dependencies closure:
dependencies {
annotationProcessor 'com.google.auto.service:auto-service:1.0-rc5'
compileOnly 'com.google.auto.service:auto-service:1.0-rc5'
}
Solution 2:[2]
It looks like you are missing a step. Running Maven build of this project will invoke the Google AutoService annotation processor, create a registration file for your custom processor, and build a .jar with it. In order for your processor to work, that .jar must be included as a dependency before compiling the project that contains Test
. Otherwise the registration file that must be picked up by Java ServiceLoader is generated during compilation and obviously not included in the compiler's classpath.
Sources
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Source: Stack Overflow
Solution | Source |
---|---|
Solution 1 | Mohsents |
Solution 2 |