/*

 * Copyright (c) 2015, 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.

 */

package build.tools.symbolgenerator;

import com.sun.source.util.JavacTask;

import com.sun.tools.javac.api.JavacTool;

import com.sun.tools.javac.util.Context;

import java.io.BufferedInputStream;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.nio.charset.Charset;

import java.util.Arrays;

import java.util.EnumSet;

import java.util.List;

import java.util.Set;

import javax.tools.JavaFileManager;

import javax.tools.JavaFileManager.Location;

import javax.tools.JavaFileObject;

import javax.tools.JavaFileObject.Kind;

import javax.tools.StandardLocation;

/**A tool to dump the content of the default javac's bootclasspath. This tool should not use any

 * features not available on the oldest supported target JDK, or not available in the boot JDK.

 *

 * For more information on use of this site, please see CreateSymbols.

 */

public class ProbeModular {

    public static void main(String... args) throws IOException {

        if (args.length != 1) {

            System.err.println("Not enough arguments.");

            System.err.println("Usage:");

            System.err.println("    java " +

                               ProbeModular.class.getName() +

                               " <output-file>");

            return ;

        }

        File outFile = new File(args[0]);

        Charset cs = Charset.forName("UTF-8");

        JavacTool tool = JavacTool.create();

        Context ctx = new Context();

        String version = System.getProperty("java.specification.version");

        JavacTask task = tool.getTask(null, null, null,

                                      Arrays.asList("--release", version),

                                      null, null, ctx);

        task.getElements().getTypeElement("java.lang.Object");

        JavaFileManager fm = ctx.get(JavaFileManager.class);

        try (OutputStream out = new FileOutputStream(outFile)) {

            for (Location modLoc : LOCATIONS) {

                for (Set<JavaFileManager.Location> module :

                        fm.listLocationsForModules(modLoc)) {

                    for (JavaFileManager.Location loc : module) {

                        Iterable<JavaFileObject> files =

                                fm.list(loc,

                                        "",

                                        EnumSet.of(Kind.CLASS),

                                        true);

                        for (JavaFileObject jfo : files) {

                            try (InputStream is = jfo.openInputStream();

                                 InputStream in =

                                         new BufferedInputStream(is)) {

                                ByteArrayOutputStream baos =

                                        new ByteArrayOutputStream();

                                StringBuilder textual = new StringBuilder();

                                int read;

                                while ((read = in.read()) != (-1)) {

                                    baos.write(read);

                                    String hex = String.format("%02x", read);

                                    textual.append(hex);

                                }

                                textual.append("\n");

                                out.write(textual.toString().getBytes(cs));

                            }

                        }

                    }

                }

            }

        }

    }

    //where:

        private static final List<StandardLocation> LOCATIONS =

                Arrays.asList(StandardLocation.SYSTEM_MODULES,

                              StandardLocation.UPGRADE_MODULE_PATH);

}