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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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
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 *
 * 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,
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package jdk.jfr.stress.javaagent;

import com.sun.tools.attach.VirtualMachine;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.jar.Attributes;
import java.util.jar.Manifest;
import jdk.jfr.consumer.RecordingFile;
import jdk.test.lib.Asserts;
import jdk.test.lib.Utils;
import jdk.test.lib.process.OutputAnalyzer;
import jdk.test.lib.process.ProcessTools;
import jdk.test.lib.util.JarUtils;

/**
 * @test
 * @key jfr
 * @summary Test event generation from within java agent
 * @requires vm.hasJFR
 *
 * @library /test/lib /test/jdk
 * @modules java.instrument
 *
 * @build JavaAgent SimpleLoop
 * @run driver jdk.jfr.stress.javaagent.TestEventsFromJavaAgent prepareAgent
 * @run main/othervm -javaagent:StressEventsAgent.jar jdk.jfr.stress.javaagent.TestEventsFromJavaAgent test
 */

public class TestEventsFromJavaAgent {
    public static void main(String... args) throws Exception {
        if(args[0].equals("prepareAgent")) {
            prepareAgent();
            return;
        }

        System.out.println("Hello from TestEventsFromJavaAgent");

        // Test Case 01: the test runs in premain() in this process.
        // The recording file can get fairly large; delete it upon exit.
        JavaAgent.RECORDING_FILE_PREMAIN.toFile().deleteOnExit();
        validateRecording(JavaAgent.RECORDING_FILE_PREMAIN);


        // Test Case 02: the test runs in agentmain() in a child process.
        testWithDynamicallyLoadedAgent();
        JavaAgent.RECORDING_FILE_AGENTMAIN.toFile().deleteOnExit();
        validateRecording(JavaAgent.RECORDING_FILE_AGENTMAIN);
    }


    // Run simple loop in a child process,
    // attach and dynamically load the agent to record events.
    private static void testWithDynamicallyLoadedAgent() throws Exception {
        ProcessBuilder pb =
            ProcessTools.createJavaProcessBuilder("jdk.jfr.stress.javaagent.SimpleLoop", "20");
        Process p = pb.start();

        VirtualMachine vm = VirtualMachine.attach("" + p.pid());
        vm.loadAgent("StressEventsAgent.jar");
        vm.detach();

        p.waitFor();
        OutputAnalyzer out = new OutputAnalyzer(p);
        System.out.println("========= child process output:");
        System.out.println(out.getOutput());
        System.out.println("========= ");
        out.shouldHaveExitValue(0)
            .shouldContain("agentmain(): done")
            .shouldNotContain("agentmain(): exception");
    }

    private static void prepareAgent() throws Exception {
        Manifest mf = new Manifest();
        Attributes attrs = mf.getMainAttributes();
        attrs.put(Attributes.Name.MANIFEST_VERSION, "1.0");
        attrs.putValue("Premain-Class", "jdk.jfr.stress.javaagent.JavaAgent");
        attrs.putValue("Agent-Class",   "jdk.jfr.stress.javaagent.JavaAgent");

        JarUtils.createJarFile(Paths.get(".", "StressEventsAgent.jar"), mf,
                               Paths.get(Utils.TEST_CLASSES),
                               Paths.get(Utils.TEST_CLASSES, "jdk", "jfr", "stress", "javaagent",
                                         "JavaAgent.class"));
    }

    private static void validateRecording(Path recordingFile) throws Exception {
        String eventName = "jdk.jfr.stress.javaagent.TestEvent";
        long testEventCount = RecordingFile.readAllEvents(recordingFile).stream()
            .filter(e -> e.getEventType().getName().equals(eventName))
            .count();

        long expectedEventCount = JavaAgent.NUMBER_OF_EVENT_GENERATOR_THREADS *
            JavaAgent.NUMBER_OF_EVENTS_PER_THREAD;
        Asserts.assertTrue(testEventCount == expectedEventCount,
                           "Mismatch in TestEvent count");
    }
}