Mercurial > jdk8-mips64-public > langtools / file revision
src/share/classes/com/sun/tools/javac/util/ByteBuffer.java@0e5899f09dab
src/share/classes/com/sun/tools/javac/util/ByteBuffer.java
Tue, 25 Sep 2012 13:06:58 -0700
- author
- jjg
- date
- Tue, 25 Sep 2012 13:06:58 -0700
- changeset 1339
- 0e5899f09dab
- parent 581
- f2fdd52e4e87
- child 2525
- 2eb010b6cb22
- permissions
- -rw-r--r--
7193657: provide internal ArrayUtils class to simplify common usage of arrays in javac
Reviewed-by: mcimadamore, jjg
Contributed-by: vicenterz@yahoo.es
1 /*
2 * Copyright (c) 1999, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
26 package com.sun.tools.javac.util;
28 import java.io.*;
30 /** A byte buffer is a flexible array which grows when elements are
31 * appended. There are also methods to append names to byte buffers
32 * and to convert byte buffers to names.
33 *
34 * <p><b>This is NOT part of any supported API.
35 * If you write code that depends on this, you do so at your own risk.
36 * This code and its internal interfaces are subject to change or
37 * deletion without notice.</b>
38 */
39 public class ByteBuffer {
41 /** An array holding the bytes in this buffer; can be grown.
42 */
43 public byte[] elems;
45 /** The current number of defined bytes in this buffer.
46 */
47 public int length;
49 /** Create a new byte buffer.
50 */
51 public ByteBuffer() {
52 this(64);
53 }
55 /** Create a new byte buffer with an initial elements array
56 * of given size.
57 */
58 public ByteBuffer(int initialSize) {
59 elems = new byte[initialSize];
60 length = 0;
61 }
63 /** Append byte to this buffer.
64 */
65 public void appendByte(int b) {
66 elems = ArrayUtils.ensureCapacity(elems, length);
67 elems[length++] = (byte)b;
68 }
70 /** Append `len' bytes from byte array,
71 * starting at given `start' offset.
72 */
73 public void appendBytes(byte[] bs, int start, int len) {
74 elems = ArrayUtils.ensureCapacity(elems, length + len);
75 System.arraycopy(bs, start, elems, length, len);
76 length += len;
77 }
79 /** Append all bytes from given byte array.
80 */
81 public void appendBytes(byte[] bs) {
82 appendBytes(bs, 0, bs.length);
83 }
85 /** Append a character as a two byte number.
86 */
87 public void appendChar(int x) {
88 elems = ArrayUtils.ensureCapacity(elems, length + 1);
89 elems[length ] = (byte)((x >> 8) & 0xFF);
90 elems[length+1] = (byte)((x ) & 0xFF);
91 length = length + 2;
92 }
94 /** Append an integer as a four byte number.
95 */
96 public void appendInt(int x) {
97 elems = ArrayUtils.ensureCapacity(elems, length + 3);
98 elems[length ] = (byte)((x >> 24) & 0xFF);
99 elems[length+1] = (byte)((x >> 16) & 0xFF);
100 elems[length+2] = (byte)((x >> 8) & 0xFF);
101 elems[length+3] = (byte)((x ) & 0xFF);
102 length = length + 4;
103 }
105 /** Append a long as an eight byte number.
106 */
107 public void appendLong(long x) {
108 ByteArrayOutputStream buffer = new ByteArrayOutputStream(8);
109 DataOutputStream bufout = new DataOutputStream(buffer);
110 try {
111 bufout.writeLong(x);
112 appendBytes(buffer.toByteArray(), 0, 8);
113 } catch (IOException e) {
114 throw new AssertionError("write");
115 }
116 }
118 /** Append a float as a four byte number.
119 */
120 public void appendFloat(float x) {
121 ByteArrayOutputStream buffer = new ByteArrayOutputStream(4);
122 DataOutputStream bufout = new DataOutputStream(buffer);
123 try {
124 bufout.writeFloat(x);
125 appendBytes(buffer.toByteArray(), 0, 4);
126 } catch (IOException e) {
127 throw new AssertionError("write");
128 }
129 }
131 /** Append a double as a eight byte number.
132 */
133 public void appendDouble(double x) {
134 ByteArrayOutputStream buffer = new ByteArrayOutputStream(8);
135 DataOutputStream bufout = new DataOutputStream(buffer);
136 try {
137 bufout.writeDouble(x);
138 appendBytes(buffer.toByteArray(), 0, 8);
139 } catch (IOException e) {
140 throw new AssertionError("write");
141 }
142 }
144 /** Append a name.
145 */
146 public void appendName(Name name) {
147 appendBytes(name.getByteArray(), name.getByteOffset(), name.getByteLength());
148 }
150 /** Reset to zero length.
151 */
152 public void reset() {
153 length = 0;
154 }
156 /** Convert contents to name.
157 */
158 public Name toName(Names names) {
159 return names.fromUtf(elems, 0, length);
160 }
161 }
