[MPLUGIN-320] JavaJavadocMojoDescriptorExtractor fails with Java 8 lambdas.

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.5
• Fix Version/s: 3.5.1
• Component/s: maven-plugin-tools-java
• Assignee: Guillaume Boué
• Reporter: Antony Riley
• Created: 21/Dec/16 10:33
• Updated: 15/Jan/17 13:04
• Resolved: 15/Jan/17 12:20

Description

JavaJavadocMojoDescriptorExtractor fails to parse the following source:

package com.example.plugin;

import com.amazonaws.AmazonWebServiceClient;
import com.amazonaws.services.ecr.AmazonECRClient;
import com.amazonaws.services.ecs.AmazonECSClient;

import java.util.function.Supplier;

public enum AmazonClients {
    ECS(AmazonECSClient::new),
    ECR(AmazonECRClient::new);

    private final Supplier<? extends AmazonWebServiceClient> supplier;

    <T extends AmazonWebServiceClient> AmazonClients(Supplier<T> supplier) {
        this.supplier = new SingletonSupplier<T>(supplier);
    }

    public <T extends AmazonWebServiceClient> T get() {
        return (T) supplier.get();
    }

    private static class SingletonSupplier<T> implements Supplier<T> {
        private final Supplier<T> realSupplier;
        private T instance;

        private SingletonSupplier(Supplier<T> realSupplier) {
            this.realSupplier = realSupplier;
        }

        @Override
        public synchronized T get() {
            return instance == null ? instance = realSupplier.get() : instance;
        }
    }
}

It fails on the lamdas in the constructors, this causes maven-plugin-plugin:helpmojo to fail with the following exception:

Caused by: com.thoughtworks.qdox.parser.ParseException: syntax error @[10,24] in file:/home/antony/work/example/src/main/java/com/example/plugin/AmazonClients.java
        at com.thoughtworks.qdox.parser.impl.Parser.yyerror(Parser.java:1739)
        at com.thoughtworks.qdox.parser.impl.Parser.yyparse(Parser.java:1861)
        at com.thoughtworks.qdox.parser.impl.Parser.parse(Parser.java:1720)
        at com.thoughtworks.qdox.library.SourceLibrary.parse(SourceLibrary.java:232)
        at com.thoughtworks.qdox.library.SourceLibrary.parse(SourceLibrary.java:209)
        at com.thoughtworks.qdox.library.SourceLibrary.addSource(SourceLibrary.java:157)
        at com.thoughtworks.qdox.library.SortedClassLibraryBuilder.addSource(SortedClassLibraryBuilder.java:173)
        at com.thoughtworks.qdox.JavaProjectBuilder.addSource(JavaProjectBuilder.java:151)
        at com.thoughtworks.qdox.JavaProjectBuilder$2.visitFile(JavaProjectBuilder.java:223)
        at com.thoughtworks.qdox.directorywalker.DirectoryScanner.walk(DirectoryScanner.java:103)
        at com.thoughtworks.qdox.directorywalker.DirectoryScanner.walk(DirectoryScanner.java:91)
        at com.thoughtworks.qdox.directorywalker.DirectoryScanner.walk(DirectoryScanner.java:91)
        at com.thoughtworks.qdox.directorywalker.DirectoryScanner.walk(DirectoryScanner.java:91)
        at com.thoughtworks.qdox.directorywalker.DirectoryScanner.walk(DirectoryScanner.java:91)
        at com.thoughtworks.qdox.directorywalker.DirectoryScanner.walk(DirectoryScanner.java:91)
        at com.thoughtworks.qdox.directorywalker.DirectoryScanner.scan(DirectoryScanner.java:81)
        at com.thoughtworks.qdox.JavaProjectBuilder.addSourceTree(JavaProjectBuilder.java:217)
        at com.thoughtworks.qdox.JavaProjectBuilder.addSourceTree(JavaProjectBuilder.java:204)
        at org.apache.maven.tools.plugin.extractor.javadoc.JavaJavadocMojoDescriptorExtractor.discoverClasses(JavaJavadocMojoDescriptorExtractor.java:625)
        at org.apache.maven.tools.plugin.extractor.javadoc.JavaJavadocMojoDescriptorExtractor.execute(JavaJavadocMojoDescriptorExtractor.java:573)
        at org.apache.maven.tools.plugin.scanner.DefaultMojoScanner.populatePluginDescriptor(DefaultMojoScanner.java:96)
        at org.apache.maven.plugin.plugin.AbstractGeneratorMojo.execute(AbstractGeneratorMojo.java:283)
        at org.apache.maven.plugin.plugin.HelpGeneratorMojo.execute(HelpGeneratorMojo.java:92)
        at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134)
        ... 21 more

Issue Links

• is related to: MPLUGIN-290 Version 3.4 fails to parse enums with Regex patterns
• relates to: MPLUGIN-314 invalid requirement role generated in plugin.xml