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25 
26 package sun.tools.jstatd;
27 
28 import java.util.*;
29 import java.nio.*;
30 import java.io.*;
31 import java.net.*;
32 import java.rmi.*;
33 import java.rmi.server.*;
34 import sun.jvmstat.monitor.*;
35 import sun.jvmstat.monitor.event.*;
36 import sun.jvmstat.monitor.remote.*;
37 
38 /**
39  * Concrete implementation of the RemoteHost interface for the HotSpot
40  * PerfData <em>rmi:</em> protocol.
41  * <p>
42  * This class provides remote access to the instrumentation exported
43  * by HotSpot Java Virtual Machines through the PerfData shared memory
44  * interface.
45  *
46  * @author Brian Doherty
47  * @since 1.5
48  */
49 public class RemoteHostImpl implements RemoteHost, HostListener {
50 
51     private MonitoredHost monitoredHost;
52     private Set<Integer> activeVms;
53     private static RemoteVm rvm;
54     private final int rmiPort;
55 
RemoteHostImpl()56     public RemoteHostImpl() throws MonitorException {
57         this(0);
58     }
59 
RemoteHostImpl(int rmiPort)60     public RemoteHostImpl(int rmiPort) throws MonitorException {
61         this.rmiPort = rmiPort;
62         try {
63             monitoredHost = MonitoredHost.getMonitoredHost("localhost");
64         } catch (URISyntaxException e) { }
65 
66         activeVms = monitoredHost.activeVms();
67         monitoredHost.addHostListener(this);
68     }
69 
attachVm(int lvmid, String mode)70     public RemoteVm attachVm(int lvmid, String mode)
71                     throws RemoteException, MonitorException {
72         Integer v = lvmid;
73         RemoteVm stub = null;
74         StringBuilder sb = new StringBuilder();
75 
76         sb.append("local://").append(lvmid).append("@localhost");
77         if (mode != null) {
78             sb.append("?mode=").append(mode);
79         }
80 
81         String vmidStr = sb.toString();
82 
83         try {
84             VmIdentifier vmid = new VmIdentifier(vmidStr);
85             MonitoredVm mvm = monitoredHost.getMonitoredVm(vmid);
86             rvm = new RemoteVmImpl((BufferedMonitoredVm)mvm);
87             stub = (RemoteVm) UnicastRemoteObject.exportObject(rvm, rmiPort);
88         }
89         catch (URISyntaxException e) {
90             throw new RuntimeException("Malformed VmIdentifier URI: "
91                                        + vmidStr, e);
92         }
93         return stub;
94     }
95 
detachVm(RemoteVm rvm)96     public void detachVm(RemoteVm rvm) throws RemoteException {
97         rvm.detach();
98     }
99 
activeVms()100     public int[] activeVms() throws MonitorException {
101         Object[] vms = null;
102         int[] vmids = null;
103 
104         vms = monitoredHost.activeVms().toArray();
105         vmids = new int[vms.length];
106 
107         for (int i = 0; i < vmids.length; i++) {
108             vmids[i] = ((Integer)vms[i]).intValue();
109         }
110         return vmids;
111     }
112 
vmStatusChanged(VmStatusChangeEvent ev)113     public void vmStatusChanged(VmStatusChangeEvent ev) {
114         synchronized(this.activeVms) {
115             activeVms.retainAll(ev.getActive());
116         }
117     }
118 
disconnected(HostEvent ev)119     public void disconnected(HostEvent ev) {
120         // we only monitor the local host, so this event shouldn't occur.
121     }
122 }
123