jdk/src/share/classes/sun/management/counter/perf/PerfDataType.java

/*
 * Copyright 2003 Sun Microsystems, Inc.  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.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

package sun.management.counter.perf;

import java.io.UnsupportedEncodingException;

/**
 * A typesafe enumeration for the data types supported for
 * performance data.
 *
 * <p> The enumeration values for this typesafe enumeration must be
 * kept in sychronization with the PerfDataType enum in the
 * globalsDefinitions.hpp file in the HotSpot source base.</p>
 *
 * @author  Brian Doherty
 */
class PerfDataType {

    private final String name;
    private final byte value;
    private final int size;

    public static final PerfDataType BOOLEAN = new PerfDataType("boolean",  "Z", 1);
    public static final PerfDataType CHAR    = new PerfDataType("char",     "C", 1);
    public static final PerfDataType FLOAT   = new PerfDataType("float",    "F", 8);
    public static final PerfDataType DOUBLE  = new PerfDataType("double",   "D", 8);
    public static final PerfDataType BYTE    = new PerfDataType("byte",     "B", 1);
    public static final PerfDataType SHORT   = new PerfDataType("short",    "S", 2);
    public static final PerfDataType INT     = new PerfDataType("int",      "I", 4);
    public static final PerfDataType LONG    = new PerfDataType("long",     "J", 8);
    public static final PerfDataType ILLEGAL = new PerfDataType("illegal",  "X", 0);

    private static PerfDataType basicTypes[] = {
        LONG, BYTE, BOOLEAN, CHAR, FLOAT, DOUBLE, SHORT, INT
    };

    public String toString() {
        return name;
    }

    public byte byteValue() {
        return value;
    }

    public int size() {
        return size;
    }

    /**
     * Maps an integer PerfDataType value to its corresponding PerfDataType
     * object.
     *
     * @param   i  an integer representation of a PerfDataType
     * @return     The PerfDataType object for <code>i</code>
     */
    public static PerfDataType toPerfDataType(byte type) {
        for (int j = 0; j < basicTypes.length; j++) {
            if (basicTypes[j].byteValue() == type) {
                return (basicTypes[j]);
            }
        }
        return ILLEGAL;
    }

    private PerfDataType(String name, String c, int size) {
        this.name = name;
        this.size = size;
        try {
            byte[] b = c.getBytes("UTF-8");
            this.value = b[0];
        } catch (UnsupportedEncodingException e) {
            // ignore, "UTF-8" is always a known encoding
            throw new InternalError("Unknown encoding");
        }
    }
}