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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
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 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package gc.metaspace;

/**
 * @test CompressedClassSpaceSizeInJmapHeap
 * @bug 8004924
 * @summary Checks that jmap -heap contains the flag CompressedClassSpaceSize
 * @requires vm.hasSA
 * @requires vm.bits == 64 & vm.opt.final.UseCompressedOops == true
 * @library /test/lib
 * @modules java.base/jdk.internal.misc
 *          java.management
 * @run main/timeout=240 gc.metaspace.CompressedClassSpaceSizeInJmapHeap
 */

import jdk.test.lib.JDKToolLauncher;
import jdk.test.lib.apps.LingeredApp;
import jdk.test.lib.process.OutputAnalyzer;
import jdk.test.lib.process.ProcessTools;
import jdk.test.lib.SA.SATestUtils;
import java.nio.file.*;
import java.io.File;
import java.nio.charset.Charset;
import java.util.List;

public class CompressedClassSpaceSizeInJmapHeap {

    // Note that on some platforms it may require root privileges to run this test.
    public static void main(String[] args) throws Exception {
        SATestUtils.skipIfCannotAttach(); // throws SkippedException if attach not expected to work.

        LingeredApp theApp = new LingeredApp();
        LingeredApp.startApp(theApp, "-XX:CompressedClassSpaceSize=48m");
        String pid = Long.toString(theApp.getPid());

        JDKToolLauncher jmap = JDKToolLauncher.create("jhsdb")
                                              .addToolArg("jmap")
                                              .addToolArg("--heap")
                                              .addToolArg("--pid")
                                              .addToolArg(pid);
        ProcessBuilder pb = SATestUtils.createProcessBuilder(jmap);

        File out = new File("CompressedClassSpaceSizeInJmapHeap.stdout.txt");
        pb.redirectOutput(out);

        File err = new File("CompressedClassSpaceSizeInJmapHeap.stderr.txt");
        pb.redirectError(err);

        // If we attempt to attach to LingeredApp before it has initialized, the heap dump request will fail, so we allow 3 tries
        int allowedTries = 3;
        int exitValue;
        do {
            exitValue = run(pb);
        } while ((exitValue != 0) && (allowedTries-- > 0));
        if (exitValue != 0) {
            throw new Exception("jmap -heap exited with error code: " + exitValue);
        }
        OutputAnalyzer output = new OutputAnalyzer(read(out));
        output.shouldContain("CompressedClassSpaceSize = 50331648 (48.0MB)");
        out.delete();

        LingeredApp.stopApp(theApp);
    }

    private static int run(ProcessBuilder pb) throws Exception {
        OutputAnalyzer output = ProcessTools.executeProcess(pb);
        return output.getExitValue();
    }

    private static String read(File f) throws Exception {
        Path p = f.toPath();
        List<String> lines = Files.readAllLines(p, Charset.defaultCharset());

        StringBuilder sb = new StringBuilder();
        for (String line : lines) {
            sb.append(line).append('\n');
        }
        return sb.toString();
    }
}
