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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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package sun.jvmstat.perfdata.monitor;
import sun.jvmstat.monitor.*;
import java.nio.ByteBuffer;
/**
* Class for monitoring a PerfData Byte Array instrumentation object.
*
* This class is provided to support the PerfStringMonitor classes.
* Instrumentation objects of this direct type currently cannot be
* created or monitored.
*
* @author Brian Doherty
* @since 1.5
* @see sun.jvmstat.instrument.ByteArrayInstrument
*/
public class PerfByteArrayMonitor extends AbstractMonitor
implements ByteArrayMonitor {
/**
* The buffer containing the data for the byte array instrument.
*/
ByteBuffer bb;
/**
* Constructor to create a ByteArrayMonitor for the byte array instrument
* represented by the data in the given buffer.
*
* @param name the name of the instrumentation object
* @param u the units of measure attribute
* @param v the variability attribute
* @param supported support level indicator
* @param bb the buffer containing the byte array instrument data
* @param vectorLength the length of the vector.
*/
public PerfByteArrayMonitor(String name, Units u, Variability v,
boolean supported, ByteBuffer bb,
int vectorLength) {
super(name, u, v, supported, vectorLength);
this.bb = bb;
}
/**
* {@inheritDoc}
* The object returned contains a byte[] with a copy of the current
* elements of the ByteArrayInstrument.
*
* @return Object - a copy of the current value of the elements of the
* byte array instrument. The return type is guaranteed
* to be of type byte[].
*/
public Object getValue() {
return byteArrayValue();
}
/**
* Get a copy of the elements of the byte array instrument.
*
* @return byte[] - a copy of the current value of the elements of the
* byte array instrument.
*/
public byte[] byteArrayValue() {
bb.position(0);
byte[] b = new byte[bb.limit()];
// copy the bytes
bb.get(b);
return b;
}
/**
* Get the current value of an element of the byte array instrument.
*
* @return byte - a copy of the current value of the element at index
* <tt>index</tt> of the byte array instrument.
*/
public byte byteAt(int index) {
bb.position(index);
return bb.get();
}
/**
* Get the maximum length of the byte array for this byte array instrument.
*
* @return int - the maximum length of the byte array.
*/
public int getMaximumLength() {
return bb.limit();
}
}