Java example source code file (MessagerDiags.java)

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Java - Java tags/keywords

abstractprocessor, cname, diagnosticcollector, ioexception, list, messagerdiags, myfileobject, net, network, none, override, string, supportedannotationtypes, test_java, util, wrn_no_source, wrn_with_source

The MessagerDiags.java Java example source code

/*
 * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/*
 * @test
 * @bug 7166010
 * @summary  warnings printed by annotation processors uses incorrect source
 */
import com.sun.source.util.JavacTask;
import java.io.IOException;
import java.net.URI;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;
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.annotation.processing.SupportedSourceVersion;
import javax.lang.model.SourceVersion;
import javax.lang.model.element.Element;
import javax.lang.model.element.TypeElement;
import javax.tools.Diagnostic;
import javax.tools.DiagnosticCollector;
import javax.tools.JavaCompiler;
import javax.tools.JavaFileObject;
import javax.tools.SimpleJavaFileObject;
import javax.tools.ToolProvider;

import static javax.tools.Diagnostic.Kind.*;
import static javax.tools.JavaFileObject.Kind.*;

@SupportedSourceVersion(SourceVersion.RELEASE_6)
@SupportedAnnotationTypes("*")
public class MessagerDiags extends AbstractProcessor {
    static final String CNAME = "Test";
    static final String TEST_JAVA = CNAME + ".java";
    static final String TEST_JAVA_URI_NAME = "myfo:/" + TEST_JAVA;
    static final String WRN_NO_SOURCE   = "warning without source";
    static final String WRN_WITH_SOURCE = "warning with source";
    static final String NONE = "<none>";
    static final String[] EXPECTED = { NONE + ":-1--1:" + WRN_NO_SOURCE,
                                       TEST_JAVA + ":0-13:" + WRN_WITH_SOURCE,
                                       NONE + ":-1--1:" + WRN_NO_SOURCE
    };

    @Override
    public boolean process(Set<? extends TypeElement> annotations,
                           RoundEnvironment roundEnv) {
        Messager messager = processingEnv.getMessager();
        for (Element e : roundEnv.getRootElements()) {
            messager.printMessage(WARNING, WRN_NO_SOURCE);
            messager.printMessage(WARNING, WRN_WITH_SOURCE, e);
            messager.printMessage(WARNING, WRN_NO_SOURCE);
        }
        return false;
    }

    public static void main(String... args) throws IOException {
        final String bootPath = System.getProperty("sun.boot.class.path");
        final JavaCompiler tool = ToolProvider.getSystemJavaCompiler();
        assert tool != null;

        DiagnosticCollector<JavaFileObject> dc = new DiagnosticCollector<>();
        List<String> options = new LinkedList<>();
        options.addAll(Arrays.asList("-bootclasspath",  bootPath,
                        "-source", "1.6", "-classpath",
                        System.getProperty("java.class.path")));
        options.addAll(Arrays.asList("-processor",
                       MessagerDiags.class.getName()));
        JavacTask ct = (JavacTask)tool.getTask(null, null, dc, options, null,
                        Arrays.asList(new MyFileObject("class " + CNAME + " {}")));
        ct.analyze();

        List<String> obtainedErrors = new ArrayList<>();

        for (Diagnostic<? extends JavaFileObject> d : dc.getDiagnostics()) {
            String dSource;
            if (d.getSource() != null) {
                dSource = d.getSource().toUri().getPath();
                dSource = dSource.substring(dSource.lastIndexOf('/') + 1);
            } else {
                dSource = NONE;
            }
            obtainedErrors.add(dSource + ":" + d.getStartPosition() + "-" +
                    d.getEndPosition() + ":" + d.getMessage(null));
        }
        List<String> expectedErrors = Arrays.asList(EXPECTED);
        if (!expectedErrors.equals(obtainedErrors)) {
            System.err.println("Expected: " + expectedErrors);
            System.err.println("Obtained: " + obtainedErrors);
            throw new AssertionError("Messages don't match");
        }
    }

    static class MyFileObject extends SimpleJavaFileObject {
        private String text;
        public MyFileObject(String text) {
            super(URI.create(TEST_JAVA_URI_NAME), SOURCE);
            this.text = text;
        }
        @Override
        public CharSequence getCharContent(boolean ignoreEncodingErrors) {
            return text;
        }
    }
}