/*

 * Copyright (c) 2003, 2016, 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 sun.management;

import jdk.internal.perf.Perf;

import sun.management.counter.*;

import sun.management.counter.perf.*;

import java.nio.ByteBuffer;

import java.io.IOException;

import java.net.InetAddress;

import java.net.UnknownHostException;

import java.util.List;

import java.util.Arrays;

import java.util.Collections;

import java.security.AccessController;

import java.security.PrivilegedAction;

/**

 * Implementation of VMManagement interface that accesses the management

 * attributes and operations locally within the same Java virtual

 * machine.

 */

class VMManagementImpl implements VMManagement {

    private static String version;

    private static boolean compTimeMonitoringSupport;

    private static boolean threadContentionMonitoringSupport;

    private static boolean currentThreadCpuTimeSupport;

    private static boolean otherThreadCpuTimeSupport;

    private static boolean objectMonitorUsageSupport;

    private static boolean synchronizerUsageSupport;

    private static boolean threadAllocatedMemorySupport;

    private static boolean gcNotificationSupport;

    private static boolean remoteDiagnosticCommandsSupport;

    static {

        version = getVersion0();

        if (version == null) {

            throw new AssertionError("Invalid Management Version");

        }

        initOptionalSupportFields();

    }

    private native static String getVersion0();

    private native static void initOptionalSupportFields();

    // Optional supports

    public boolean isCompilationTimeMonitoringSupported() {

        return compTimeMonitoringSupport;

    }

    public boolean isThreadContentionMonitoringSupported() {

        return threadContentionMonitoringSupport;

    }

    public boolean isCurrentThreadCpuTimeSupported() {

        return currentThreadCpuTimeSupport;

    }

    public boolean isOtherThreadCpuTimeSupported() {

        return otherThreadCpuTimeSupport;

    }

    public boolean isBootClassPathSupported() {

        return false;

    }

    public boolean isObjectMonitorUsageSupported() {

        return objectMonitorUsageSupport;

    }

    public boolean isSynchronizerUsageSupported() {

        return synchronizerUsageSupport;

    }

    public boolean isThreadAllocatedMemorySupported() {

        return threadAllocatedMemorySupport;

    }

    public boolean isGcNotificationSupported() {

        boolean isSupported = true;

        try {

            Class.forName("com.sun.management.GarbageCollectorMXBean");

        } catch (ClassNotFoundException x) {

            isSupported = false;

        }

        return isSupported;

    }

    public boolean isRemoteDiagnosticCommandsSupported() {

        return remoteDiagnosticCommandsSupport;

    }

    public native boolean isThreadContentionMonitoringEnabled();

    public native boolean isThreadCpuTimeEnabled();

    public native boolean isThreadAllocatedMemoryEnabled();

    // Class Loading Subsystem

    public int    getLoadedClassCount() {

        long count = getTotalClassCount() - getUnloadedClassCount();

        return (int) count;

    }

    public native long getTotalClassCount();

    public native long getUnloadedClassCount();

    public native boolean getVerboseClass();

    // Memory Subsystem

    public native boolean getVerboseGC();

    // Runtime Subsystem

    public String   getManagementVersion() {

        return version;

    }

    public String getVmId() {

        int pid = getProcessId();

        String hostname = "localhost";

        try {

            hostname = InetAddress.getLocalHost().getHostName();

        } catch (UnknownHostException e) {

            // ignore

        }

        return pid + "@" + hostname;

    }

    private native int getProcessId();

    public String   getVmName() {

        return System.getProperty("java.vm.name");

    }

    public String   getVmVendor() {

        return System.getProperty("java.vm.vendor");

    }

    public String   getVmVersion() {

        return System.getProperty("java.vm.version");

    }

    public String   getVmSpecName()  {

        return System.getProperty("java.vm.specification.name");

    }

    public String   getVmSpecVendor() {

        return System.getProperty("java.vm.specification.vendor");

    }

    public String   getVmSpecVersion() {

        return System.getProperty("java.vm.specification.version");

    }

    public String   getClassPath() {

        return System.getProperty("java.class.path");

    }

    public String   getLibraryPath()  {

        return System.getProperty("java.library.path");

    }

    public String   getBootClassPath( ) {

        throw new UnsupportedOperationException(

            "Boot class path mechanism is not supported");

    }

    public long getUptime() {

        return getUptime0();

    }

    private List<String> vmArgs = null;

    public synchronized List<String> getVmArguments() {

        if (vmArgs == null) {

            String[] args = getVmArguments0();

            List<String> l = ((args != null && args.length != 0) ? Arrays.asList(args) :

                                        Collections.<String>emptyList());

            vmArgs = Collections.unmodifiableList(l);

        }

        return vmArgs;

    }

    public native String[] getVmArguments0();

    public native long getStartupTime();

    private native long getUptime0();

    public native int getAvailableProcessors();

    // Compilation Subsystem

    public String   getCompilerName() {

        String name =  AccessController.doPrivileged(

            new PrivilegedAction<String>() {

                public String run() {

                    return System.getProperty("sun.management.compiler");

                }

            });

        return name;

    }

    public native long getTotalCompileTime();

    // Thread Subsystem

    public native long getTotalThreadCount();

    public native int  getLiveThreadCount();

    public native int  getPeakThreadCount();

    public native int  getDaemonThreadCount();

    // Operating System

    public String getOsName() {

        return System.getProperty("os.name");

    }

    public String getOsArch() {

        return System.getProperty("os.arch");

    }

    public String getOsVersion() {

        return System.getProperty("os.version");

    }

    // Hotspot-specific runtime support

    public native long getSafepointCount();

    public native long getTotalSafepointTime();

    public native long getSafepointSyncTime();

    public native long getTotalApplicationNonStoppedTime();

    public native long getLoadedClassSize();

    public native long getUnloadedClassSize();

    public native long getClassLoadingTime();

    public native long getMethodDataSize();

    public native long getInitializedClassCount();

    public native long getClassInitializationTime();

    public native long getClassVerificationTime();

    // Performance Counter Support

    private PerfInstrumentation perfInstr = null;

    private boolean noPerfData = false;

    private synchronized PerfInstrumentation getPerfInstrumentation() {

        if (noPerfData || perfInstr != null) {

             return perfInstr;

        }

        // construct PerfInstrumentation object

        Perf perf =  AccessController.doPrivileged(new Perf.GetPerfAction());

        try {

            ByteBuffer bb = perf.attach(0, "r");

            if (bb.capacity() == 0) {

                noPerfData = true;

                return null;

            }

            perfInstr = new PerfInstrumentation(bb);

        } catch (IllegalArgumentException e) {

            // If the shared memory doesn't exist e.g. if -XX:-UsePerfData

            // was set

            noPerfData = true;

        } catch (IOException e) {

            throw new AssertionError(e);

        }

        return perfInstr;

    }

    public List<Counter> getInternalCounters(String pattern) {

        PerfInstrumentation perf = getPerfInstrumentation();

        if (perf != null) {

            return perf.findByPattern(pattern);

        } else {

            return Collections.emptyList();

        }

    }

}