001: /*
002: * Copyright 2001-2005 Sun Microsystems, Inc. All Rights Reserved.
003: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004: *
005: * This code is free software; you can redistribute it and/or modify it
006: * under the terms of the GNU General Public License version 2 only, as
007: * published by the Free Software Foundation. Sun designates this
008: * particular file as subject to the "Classpath" exception as provided
009: * by Sun in the LICENSE file that accompanied this code.
010: *
011: * This code is distributed in the hope that it will be useful, but WITHOUT
012: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
014: * version 2 for more details (a copy is included in the LICENSE file that
015: * accompanied this code).
016: *
017: * You should have received a copy of the GNU General Public License version
018: * 2 along with this work; if not, write to the Free Software Foundation,
019: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020: *
021: * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
022: * CA 95054 USA or visit www.sun.com if you need additional information or
023: * have any questions.
024: */
025:
026: package java.io;
027:
028: /**
029: * Utility methods for packing/unpacking primitive values in/out of byte arrays
030: * using big-endian byte ordering.
031: */
032: class Bits {
033:
034: /*
035: * Methods for unpacking primitive values from byte arrays starting at
036: * given offsets.
037: */
038:
039: static boolean getBoolean(byte[] b, int off) {
040: return b[off] != 0;
041: }
042:
043: static char getChar(byte[] b, int off) {
044: return (char) (((b[off + 1] & 0xFF) << 0) + ((b[off + 0]) << 8));
045: }
046:
047: static short getShort(byte[] b, int off) {
048: return (short) (((b[off + 1] & 0xFF) << 0) + ((b[off + 0]) << 8));
049: }
050:
051: static int getInt(byte[] b, int off) {
052: return ((b[off + 3] & 0xFF) << 0) + ((b[off + 2] & 0xFF) << 8)
053: + ((b[off + 1] & 0xFF) << 16) + ((b[off + 0]) << 24);
054: }
055:
056: static float getFloat(byte[] b, int off) {
057: int i = ((b[off + 3] & 0xFF) << 0) + ((b[off + 2] & 0xFF) << 8)
058: + ((b[off + 1] & 0xFF) << 16) + ((b[off + 0]) << 24);
059: return Float.intBitsToFloat(i);
060: }
061:
062: static long getLong(byte[] b, int off) {
063: return ((b[off + 7] & 0xFFL) << 0)
064: + ((b[off + 6] & 0xFFL) << 8)
065: + ((b[off + 5] & 0xFFL) << 16)
066: + ((b[off + 4] & 0xFFL) << 24)
067: + ((b[off + 3] & 0xFFL) << 32)
068: + ((b[off + 2] & 0xFFL) << 40)
069: + ((b[off + 1] & 0xFFL) << 48)
070: + (((long) b[off + 0]) << 56);
071: }
072:
073: static double getDouble(byte[] b, int off) {
074: long j = ((b[off + 7] & 0xFFL) << 0)
075: + ((b[off + 6] & 0xFFL) << 8)
076: + ((b[off + 5] & 0xFFL) << 16)
077: + ((b[off + 4] & 0xFFL) << 24)
078: + ((b[off + 3] & 0xFFL) << 32)
079: + ((b[off + 2] & 0xFFL) << 40)
080: + ((b[off + 1] & 0xFFL) << 48)
081: + (((long) b[off + 0]) << 56);
082: return Double.longBitsToDouble(j);
083: }
084:
085: /*
086: * Methods for packing primitive values into byte arrays starting at given
087: * offsets.
088: */
089:
090: static void putBoolean(byte[] b, int off, boolean val) {
091: b[off] = (byte) (val ? 1 : 0);
092: }
093:
094: static void putChar(byte[] b, int off, char val) {
095: b[off + 1] = (byte) (val >>> 0);
096: b[off + 0] = (byte) (val >>> 8);
097: }
098:
099: static void putShort(byte[] b, int off, short val) {
100: b[off + 1] = (byte) (val >>> 0);
101: b[off + 0] = (byte) (val >>> 8);
102: }
103:
104: static void putInt(byte[] b, int off, int val) {
105: b[off + 3] = (byte) (val >>> 0);
106: b[off + 2] = (byte) (val >>> 8);
107: b[off + 1] = (byte) (val >>> 16);
108: b[off + 0] = (byte) (val >>> 24);
109: }
110:
111: static void putFloat(byte[] b, int off, float val) {
112: int i = Float.floatToIntBits(val);
113: b[off + 3] = (byte) (i >>> 0);
114: b[off + 2] = (byte) (i >>> 8);
115: b[off + 1] = (byte) (i >>> 16);
116: b[off + 0] = (byte) (i >>> 24);
117: }
118:
119: static void putLong(byte[] b, int off, long val) {
120: b[off + 7] = (byte) (val >>> 0);
121: b[off + 6] = (byte) (val >>> 8);
122: b[off + 5] = (byte) (val >>> 16);
123: b[off + 4] = (byte) (val >>> 24);
124: b[off + 3] = (byte) (val >>> 32);
125: b[off + 2] = (byte) (val >>> 40);
126: b[off + 1] = (byte) (val >>> 48);
127: b[off + 0] = (byte) (val >>> 56);
128: }
129:
130: static void putDouble(byte[] b, int off, double val) {
131: long j = Double.doubleToLongBits(val);
132: b[off + 7] = (byte) (j >>> 0);
133: b[off + 6] = (byte) (j >>> 8);
134: b[off + 5] = (byte) (j >>> 16);
135: b[off + 4] = (byte) (j >>> 24);
136: b[off + 3] = (byte) (j >>> 32);
137: b[off + 2] = (byte) (j >>> 40);
138: b[off + 1] = (byte) (j >>> 48);
139: b[off + 0] = (byte) (j >>> 56);
140: }
141: }
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