/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
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*
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* 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).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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package sun.jvmstat.perfdata.monitor.protocol.rmi;
import sun.jvmstat.monitor.*;
import sun.jvmstat.monitor.remote.*;
import sun.jvmstat.perfdata.monitor.*;
import java.io.*;
import java.rmi.RemoteException;
import java.nio.ByteBuffer;
/**
* The concrete PerfDataBuffer implementation for the <em>rmi:</em>
* protocol for the HotSpot PerfData monitoring implementation.
* <p>
* This class is responsible for acquiring the instrumentation buffer
* data for a remote target HotSpot Java Virtual Machine.
*
* @author Brian Doherty
* @since 1.5
*/
public class PerfDataBuffer extends AbstractPerfDataBuffer {
private RemoteVm rvm;
/**
* Create a PerfDataBuffer instance for accessing the specified
* instrumentation buffer.
*
* @param rvm the proxy to the remote MonitredVm object
* @param lvmid the local Java Virtual Machine Identifier of the
* remote target.
*
* @throws MonitorException
*/
public PerfDataBuffer(RemoteVm rvm, int lvmid) throws MonitorException {
this.rvm = rvm;
try {
ByteBuffer buffer = ByteBuffer.allocate(rvm.getCapacity());
sample(buffer);
createPerfDataBuffer(buffer, lvmid);
} catch (RemoteException e) {
throw new MonitorException("Could not read data for remote JVM "
+ lvmid, e);
}
}
/**
* Get a copy of the remote instrumentation buffer.
*<p>
* The data in the remote instrumentation buffer is copied into
* the local byte buffer.
*
* @param buffer the buffer to receive the copy of the remote
* instrumentation buffer.
* @throws RemoteException Thrown on any communications errors with
* the remote system.
*/
public void sample(ByteBuffer buffer) throws RemoteException {
assert buffer != null;
assert rvm != null;
synchronized(buffer) {
buffer.clear();
buffer.put(rvm.getBytes());
}
}
}