/*
 * Copyright (c) 2005, 2011, 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
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package sun.tools.attach;

import com.sun.tools.attach.VirtualMachineDescriptor;
import com.sun.tools.attach.VirtualMachine;
import com.sun.tools.attach.AttachPermission;
import com.sun.tools.attach.AttachNotSupportedException;
import com.sun.tools.attach.spi.AttachProvider;

import java.io.IOException;
import java.util.List;
import java.util.Iterator;
import java.util.ArrayList;
import java.util.Set;
import java.net.URISyntaxException;

import sun.jvmstat.monitor.HostIdentifier;
import sun.jvmstat.monitor.Monitor;
import sun.jvmstat.monitor.MonitoredHost;
import sun.jvmstat.monitor.MonitoredVm;
import sun.jvmstat.monitor.MonitoredVmUtil;
import sun.jvmstat.monitor.VmIdentifier;
import sun.jvmstat.monitor.MonitorException;

/*
 * Platform specific provider implementations extend this
 */
public abstract class HotSpotAttachProvider extends AttachProvider {

    // perf count name for the JVM version
    private static final String JVM_VERSION = "java.property.java.vm.version";

    public HotSpotAttachProvider() {
    }

    public void checkAttachPermission() {
        SecurityManager sm = System.getSecurityManager();
        if (sm != null) {
            sm.checkPermission(
                new AttachPermission("attachVirtualMachine")
            );
        }
    }

    /*
     * This listVirtualMachines implementation is based on jvmstat. Can override
     * this in platform implementations when there is a more efficient mechanism
     * available.
     */
    public List<VirtualMachineDescriptor> listVirtualMachines() {
        ArrayList<VirtualMachineDescriptor> result =
            new ArrayList<VirtualMachineDescriptor>();

        MonitoredHost host;
        Set<Integer> vms;
        try {
            host = MonitoredHost.getMonitoredHost(new HostIdentifier((String)null));
            vms = host.activeVms();
        } catch (Throwable t) {
            if (t instanceof ExceptionInInitializerError) {
                t = t.getCause();
            }
            if (t instanceof ThreadDeath) {
                throw (ThreadDeath)t;
            }
            if (t instanceof SecurityException) {
                return result;
            }
            throw new InternalError();          // shouldn't happen
        }

        for (Integer vmid: vms) {
            String pid = vmid.toString();
            String name = pid;      // default to pid if name not available
            boolean isAttachable = false;
            MonitoredVm mvm = null;
            try {
                mvm = host.getMonitoredVm(new VmIdentifier(pid));
                try {
                    isAttachable = MonitoredVmUtil.isAttachable(mvm);
                    // use the command line as the display name
                    name =  MonitoredVmUtil.commandLine(mvm);
                } catch (Exception e) {
                }
                if (isAttachable) {
                    result.add(new HotSpotVirtualMachineDescriptor(this, pid, name));
                }
            } catch (Throwable t) {
                if (t instanceof ThreadDeath) {
                    throw (ThreadDeath)t;
                }
            } finally {
                if (mvm != null) {
                    mvm.detach();
                }
            }
        }
        return result;
    }

    
Test if a VM is attachable. If it's not attachable, an AttachNotSupportedException will be thrown. For example, 1.4.2 or 5.0 VM are not attachable. There are cases that we can't determine if a VM is attachable or not and this method will just return. This method uses the jvmstat counter to determine if a VM is attachable. If the target VM does not have a jvmstat share memory buffer, this method returns.
Throws:
  • AttachNotSupportedException – if it's not attachable
/** * Test if a VM is attachable. If it's not attachable, * an AttachNotSupportedException will be thrown. For example, * 1.4.2 or 5.0 VM are not attachable. There are cases that * we can't determine if a VM is attachable or not and this method * will just return. * * This method uses the jvmstat counter to determine if a VM * is attachable. If the target VM does not have a jvmstat * share memory buffer, this method returns. * * @exception AttachNotSupportedException if it's not attachable */
void testAttachable(String id) throws AttachNotSupportedException { MonitoredVm mvm = null; try { VmIdentifier vmid = new VmIdentifier(id); MonitoredHost host = MonitoredHost.getMonitoredHost(vmid); mvm = host.getMonitoredVm(vmid); if (MonitoredVmUtil.isAttachable(mvm)) { // it's attachable; so return false return; } } catch (Throwable t) { if (t instanceof ThreadDeath) { ThreadDeath td = (ThreadDeath)t; throw td; } // we do not know what this id is return; } finally { if (mvm != null) { mvm.detach(); } } // we're sure it's not attachable; throw exception throw new AttachNotSupportedException( "The VM does not support the attach mechanism"); }
A virtual machine descriptor to describe a HotSpot virtual machine.
/** * A virtual machine descriptor to describe a HotSpot virtual machine. */
static class HotSpotVirtualMachineDescriptor extends VirtualMachineDescriptor { HotSpotVirtualMachineDescriptor(AttachProvider provider, String id, String displayName) { super(provider, id, displayName); } public boolean isAttachable() { return true; } } }