forked from XWxiaowei/JavaCode
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathOutputStreamWriter.java
More file actions
235 lines (218 loc) · 6.58 KB
/
OutputStreamWriter.java
File metadata and controls
235 lines (218 loc) · 6.58 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
/*
* Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*/
package java.io;
import java.nio.charset.Charset;
import java.nio.charset.CharsetEncoder;
import sun.nio.cs.StreamEncoder;
/**
* An OutputStreamWriter is a bridge from character streams to byte streams:
* Characters written to it are encoded into bytes using a specified {@link
* java.nio.charset.Charset charset}. The charset that it uses
* may be specified by name or may be given explicitly, or the platform's
* default charset may be accepted.
*
* <p> Each invocation of a write() method causes the encoding converter to be
* invoked on the given character(s). The resulting bytes are accumulated in a
* buffer before being written to the underlying output stream. The size of
* this buffer may be specified, but by default it is large enough for most
* purposes. Note that the characters passed to the write() methods are not
* buffered.
*
* <p> For top efficiency, consider wrapping an OutputStreamWriter within a
* BufferedWriter so as to avoid frequent converter invocations. For example:
*
* <pre>
* Writer out
* = new BufferedWriter(new OutputStreamWriter(System.out));
* </pre>
*
* <p> A <i>surrogate pair</i> is a character represented by a sequence of two
* <tt>char</tt> values: A <i>high</i> surrogate in the range '\uD800' to
* '\uDBFF' followed by a <i>low</i> surrogate in the range '\uDC00' to
* '\uDFFF'.
*
* <p> A <i>malformed surrogate element</i> is a high surrogate that is not
* followed by a low surrogate or a low surrogate that is not preceded by a
* high surrogate.
*
* <p> This class always replaces malformed surrogate elements and unmappable
* character sequences with the charset's default <i>substitution sequence</i>.
* The {@linkplain java.nio.charset.CharsetEncoder} class should be used when more
* control over the encoding process is required.
*
* @see BufferedWriter
* @see OutputStream
* @see java.nio.charset.Charset
*
* @author Mark Reinhold
* @since JDK1.1
*/
public class OutputStreamWriter extends Writer {
private final StreamEncoder se;
/**
* Creates an OutputStreamWriter that uses the named charset.
*
* @param out
* An OutputStream
*
* @param charsetName
* The name of a supported
* {@link java.nio.charset.Charset charset}
*
* @exception UnsupportedEncodingException
* If the named encoding is not supported
*/
public OutputStreamWriter(OutputStream out, String charsetName)
throws UnsupportedEncodingException
{
super(out);
if (charsetName == null)
throw new NullPointerException("charsetName");
se = StreamEncoder.forOutputStreamWriter(out, this, charsetName);
}
/**
* Creates an OutputStreamWriter that uses the default character encoding.
*
* @param out An OutputStream
*/
public OutputStreamWriter(OutputStream out) {
super(out);
try {
se = StreamEncoder.forOutputStreamWriter(out, this, (String)null);
} catch (UnsupportedEncodingException e) {
throw new Error(e);
}
}
/**
* Creates an OutputStreamWriter that uses the given charset.
*
* @param out
* An OutputStream
*
* @param cs
* A charset
*
* @since 1.4
* @spec JSR-51
*/
public OutputStreamWriter(OutputStream out, Charset cs) {
super(out);
if (cs == null)
throw new NullPointerException("charset");
se = StreamEncoder.forOutputStreamWriter(out, this, cs);
}
/**
* Creates an OutputStreamWriter that uses the given charset encoder.
*
* @param out
* An OutputStream
*
* @param enc
* A charset encoder
*
* @since 1.4
* @spec JSR-51
*/
public OutputStreamWriter(OutputStream out, CharsetEncoder enc) {
super(out);
if (enc == null)
throw new NullPointerException("charset encoder");
se = StreamEncoder.forOutputStreamWriter(out, this, enc);
}
/**
* Returns the name of the character encoding being used by this stream.
*
* <p> If the encoding has an historical name then that name is returned;
* otherwise the encoding's canonical name is returned.
*
* <p> If this instance was created with the {@link
* #OutputStreamWriter(OutputStream, String)} constructor then the returned
* name, being unique for the encoding, may differ from the name passed to
* the constructor. This method may return <tt>null</tt> if the stream has
* been closed. </p>
*
* @return The historical name of this encoding, or possibly
* <code>null</code> if the stream has been closed
*
* @see java.nio.charset.Charset
*
* @revised 1.4
* @spec JSR-51
*/
public String getEncoding() {
return se.getEncoding();
}
/**
* Flushes the output buffer to the underlying byte stream, without flushing
* the byte stream itself. This method is non-private only so that it may
* be invoked by PrintStream.
*/
void flushBuffer() throws IOException {
se.flushBuffer();
}
/**
* Writes a single character.
*
* @exception IOException If an I/O error occurs
*/
public void write(int c) throws IOException {
se.write(c);
}
/**
* Writes a portion of an array of characters.
*
* @param cbuf Buffer of characters
* @param off Offset from which to start writing characters
* @param len Number of characters to write
*
* @exception IOException If an I/O error occurs
*/
public void write(char cbuf[], int off, int len) throws IOException {
se.write(cbuf, off, len);
}
/**
* Writes a portion of a string.
*
* @param str A String
* @param off Offset from which to start writing characters
* @param len Number of characters to write
*
* @exception IOException If an I/O error occurs
*/
public void write(String str, int off, int len) throws IOException {
se.write(str, off, len);
}
/**
* Flushes the stream.
*
* @exception IOException If an I/O error occurs
*/
public void flush() throws IOException {
se.flush();
}
public void close() throws IOException {
se.close();
}
}