/* * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * 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). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ 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();    }}