1 /*
2 * Copyright (c) 2000, 2019, 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 */
25
26 package java.nio;
27
28 import java.util.Objects;
29
30 // ## If the sequence is a string, use reflection to share its array
31
32 class StringCharBuffer // package-private
33 extends CharBuffer
34 {
35 CharSequence str;
36
37 StringCharBuffer(CharSequence s, int start, int end) { // package-private
38 super(-1, start, end, s.length());
39 int n = s.length();
40 if ((start < 0) || (start > n) || (end < start) || (end > n))
41 throw new IndexOutOfBoundsException();
42 str = s;
43 this.isReadOnly = true;
44 }
45
46 public CharBuffer slice() {
47 return new StringCharBuffer(str,
48 -1,
49 0,
50 this.remaining(),
51 this.remaining(),
52 offset + this.position());
53 }
54
55 @Override
56 public CharBuffer slice(int index, int length) {
57 Objects.checkFromIndexSize(index, length, limit());
58 return new StringCharBuffer(str,
59 -1,
60 0,
61 length,
62 length,
63 offset + index);
64 }
65
66 private StringCharBuffer(CharSequence s,
67 int mark,
68 int pos,
69 int limit,
70 int cap,
71 int offset) {
72 super(mark, pos, limit, cap, null, offset);
73 str = s;
74 this.isReadOnly = true;
75 }
76
77 public CharBuffer duplicate() {
78 return new StringCharBuffer(str, markValue(),
79 position(), limit(), capacity(), offset);
80 }
81
82 public CharBuffer asReadOnlyBuffer() {
83 return duplicate();
84 }
85
86 public final char get() {
87 return str.charAt(nextGetIndex() + offset);
88 }
89
90 public final char get(int index) {
91 return str.charAt(checkIndex(index) + offset);
92 }
93
94 char getUnchecked(int index) {
95 return str.charAt(index + offset);
96 }
97
98 // ## Override bulk get methods for better performance
99
100 public final CharBuffer put(char c) {
101 throw new ReadOnlyBufferException();
102 }
103
104 public final CharBuffer put(int index, char c) {
105 throw new ReadOnlyBufferException();
106 }
107
108 public final CharBuffer compact() {
109 throw new ReadOnlyBufferException();
110 }
111
112 public final boolean isReadOnly() {
113 return true;
114 }
115
116 final String toString(int start, int end) {
117 return str.subSequence(start + offset, end + offset).toString();
118 }
119
120 public final CharBuffer subSequence(int start, int end) {
121 try {
122 int pos = position();
123 return new StringCharBuffer(str,
124 -1,
125 pos + checkIndex(start, pos),
126 pos + checkIndex(end, pos),
127 capacity(),
128 offset);
129 } catch (IllegalArgumentException x) {
130 throw new IndexOutOfBoundsException();
131 }
132 }
133
134 public boolean isDirect() {
135 return false;
136 }
137
138 public ByteOrder order() {
139 return ByteOrder.nativeOrder();
140 }
141
142 ByteOrder charRegionOrder() {
143 return null;
144 }
145
146 public boolean equals(Object ob) {
147 if (this == ob)
148 return true;
149 if (!(ob instanceof CharBuffer))
150 return false;
151 CharBuffer that = (CharBuffer)ob;
152 if (this.remaining() != that.remaining())
153 return false;
154 return BufferMismatch.mismatch(this, this.position(),
155 that, that.position(),
156 this.remaining()) < 0;
157 }
158
159 public int compareTo(CharBuffer that) {
160 int i = BufferMismatch.mismatch(this, this.position(),
161 that, that.position(),
162 Math.min(this.remaining(), that.remaining()));
163 if (i >= 0) {
164 return Character.compare(this.get(this.position() + i), that.get(that.position() + i));
165 }
166 return this.remaining() - that.remaining();
167 }
168 }