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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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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;

import sun.jvmstat.monitor.*;
import java.nio.ByteBuffer;
import java.nio.charset.Charset;

Class for monitoring a PerfData String instrument.
Author:
Brian Doherty
Since:
1.5/**
 * Class for monitoring a PerfData String instrument.
 *
 * @author Brian Doherty
 * @since 1.5
 */
public class PerfStringMonitor extends PerfByteArrayMonitor
       implements StringMonitor {

    private static Charset defaultCharset = Charset.defaultCharset();

    
Constructor to create a StringMonitor object for the string instrument
represented by the data in the given buffer.
Params:
name – the name of the string instrument
v – the variability attribute
supported – support level indicator
bb – the buffer containing the string instrument data./**
     * Constructor to create a StringMonitor object for the string instrument
     * represented by the data in the given buffer.
     *
     * @param name the name of the string instrument
     * @param v the variability attribute
     * @param supported support level indicator
     * @param bb the buffer containing the string instrument data.
     */
    public PerfStringMonitor(String name, Variability v, boolean supported,
                             ByteBuffer bb) {
        this(name, v, supported, bb, bb.limit());
    }

    
Constructor to create a StringMonitor object for the string instrument
represented by the data in the given buffer.
Params:
name – the name of the string instrument
v – the variability attribute
supported – support level indicator
bb – the buffer containing the string instrument data.
maxLength – the maximum length of the string data./**
     * Constructor to create a StringMonitor object for the string instrument
     * represented by the data in the given buffer.
     *
     * @param name the name of the string instrument
     * @param v the variability attribute
     * @param supported support level indicator
     * @param bb the buffer containing the string instrument data.
     * @param maxLength the maximum length of the string data.
     */
    public PerfStringMonitor(String name, Variability v, boolean supported,
                             ByteBuffer bb, int maxLength) {
        super(name, Units.STRING, v, supported, bb, maxLength);
    }

    
{@inheritDoc}
The object returned contains a String with a copy of the current
value of the StringInstrument.
Returns:
Object - a copy of the current value of the StringInstrument.
                 The return value is guaranteed to be of type String./**
     * {@inheritDoc}
     * The object returned contains a String with a copy of the current
     * value of the StringInstrument.
     *
     * @return Object - a copy of the current value of the StringInstrument.
     *                  The return value is guaranteed to be of type String.
     */
    public Object getValue() {
        return stringValue();
    }

    
Return the current value of the StringInstrument as a String.
Returns:
String - a copy of the current value of the StringInstrument./**
     * Return the current value of the StringInstrument as a String.
     *
     * @return String - a copy of the current value of the StringInstrument.
     */
    public String stringValue() {
        String str = "";
        byte[] b = byteArrayValue();

        // catch null strings
        if ((b == null) || (b.length <= 1) || (b[0] == (byte)0)) {
            return str;
        }

        int i;
        for (i = 0; i < b.length && b[i] != (byte)0; i++);

        return new String(b, 0, i, defaultCharset);
    }
}