Java example source code file (TestJavacTask.java)

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Java - Java tags/keywords

error, file, illegalargumentexception, ioexception, iterable, javacompiler, javactaskimpl, javafileobject, runtimeexception, standardjavafilemanager, string, testjavactask, typeelement, util

The TestJavacTask.java Java example source code

/*
 * Copyright (c) 2005, 2013, 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.
 *
 * 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     4813736 8015073
 * @summary Provide a basic test of access to the Java Model from javac, and error messages
 * @author  Peter von der Ah\u00e9
 * @run main TestJavacTask TestJavacTask.java
 */

import com.sun.tools.javac.api.JavacTaskImpl;
import java.io.File;
import java.io.IOException;
import java.util.Arrays;
import javax.lang.model.element.TypeElement;
import javax.tools.JavaCompiler;
import javax.tools.JavaFileObject;
import javax.tools.StandardJavaFileManager;
import javax.tools.ToolProvider;

public class TestJavacTask {
    static final JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
    static JavacTaskImpl getTask(File... file) {
        StandardJavaFileManager fm = compiler.getStandardFileManager(null, null, null);
        Iterable<? extends JavaFileObject> files =
            fm.getJavaFileObjectsFromFiles(Arrays.asList(file));
        return (JavacTaskImpl)compiler.getTask(null, fm, null, null, null, files);
    }

    static void basicTest(String... args) throws IOException {
        String srcdir = System.getProperty("test.src");
        File file = new File(srcdir, args[0]);
        JavacTaskImpl task = getTask(file);
        for (TypeElement clazz : task.enter(task.parse()))
            System.out.println(clazz.getSimpleName());
    }

    static void checkKindError() {
        final File testFile = new File("Test.java "); // <-note trailing space!
        try {
            getTask(testFile);
        } catch (IllegalArgumentException iae) {
            if (!iae.getMessage().contains("\"" + testFile.getName() + "\"")) {
                System.err.println("Got message: " + iae.getMessage());
                throw new RuntimeException("Error: expected string not found");
            }
        }
    }

    public static void main(String... args) throws IOException {
        basicTest(args);
        checkKindError();
    }
}