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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 
RemoteHostImpl()55     public RemoteHostImpl() throws MonitorException {
56         try {
57             monitoredHost = MonitoredHost.getMonitoredHost("localhost");
58         } catch (URISyntaxException e) { }
59 
60         activeVms = monitoredHost.activeVms();
61         monitoredHost.addHostListener(this);
62     }
63 
attachVm(int lvmid, String mode)64     public RemoteVm attachVm(int lvmid, String mode)
65                     throws RemoteException, MonitorException {
66         Integer v = lvmid;
67         RemoteVm stub = null;
68         StringBuilder sb = new StringBuilder();
69 
70         sb.append("local://").append(lvmid).append("@localhost");
71         if (mode != null) {
72             sb.append("?mode=").append(mode);
73         }
74 
75         String vmidStr = sb.toString();
76 
77         try {
78             VmIdentifier vmid = new VmIdentifier(vmidStr);
79             MonitoredVm mvm = monitoredHost.getMonitoredVm(vmid);
80             rvm = new RemoteVmImpl((BufferedMonitoredVm)mvm);
81             stub = (RemoteVm) UnicastRemoteObject.exportObject(rvm, 0);
82         }
83         catch (URISyntaxException e) {
84             throw new RuntimeException("Malformed VmIdentifier URI: "
85                                        + vmidStr, e);
86         }
87         return stub;
88     }
89 
detachVm(RemoteVm rvm)90     public void detachVm(RemoteVm rvm) throws RemoteException {
91         rvm.detach();
92     }
93 
activeVms()94     public int[] activeVms() throws MonitorException {
95         Object[] vms = null;
96         int[] vmids = null;
97 
98         vms = monitoredHost.activeVms().toArray();
99         vmids = new int[vms.length];
100 
101         for (int i = 0; i < vmids.length; i++) {
102             vmids[i] = ((Integer)vms[i]).intValue();
103         }
104         return vmids;
105     }
106 
vmStatusChanged(VmStatusChangeEvent ev)107     public void vmStatusChanged(VmStatusChangeEvent ev) {
108         synchronized(this.activeVms) {
109             activeVms.retainAll(ev.getActive());
110         }
111     }
112 
disconnected(HostEvent ev)113     public void disconnected(HostEvent ev) {
114         // we only monitor the local host, so this event shouldn't occur.
115     }
116 }
117