1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.io.output;
18
19 import java.io.FilterWriter;
20 import java.io.IOException;
21 import java.io.Writer;
22
23 /**
24 * A Proxy stream which acts as expected, that is it passes the method
25 * calls on to the proxied stream and doesn't change which methods are
26 * being called. It is an alternative base class to FilterWriter
27 * to increase reusability, because FilterWriter changes the
28 * methods being called, such as write(char[]) to write(char[], int, int)
29 * and write(String) to write(String, int, int).
30 *
31 * @author Stephen Colebourne
32 * @version $Id: ProxyWriter.java 619144 2008-02-06 20:23:25Z niallp $
33 */
34 public class ProxyWriter extends FilterWriter {
35
36 /**
37 * Constructs a new ProxyWriter.
38 *
39 * @param proxy the Writer to delegate to
40 */
41 public ProxyWriter(Writer proxy) {
42 super(proxy);
43 // the proxy is stored in a protected superclass variable named 'out'
44 }
45
46 /**
47 * Invokes the delegate's <code>append(char)</code> method.
48 * @param c The character to write
49 * @return this writer
50 * @throws IOException if an I/O error occurs
51 * @since IO 2.0
52 */
53 public Writer append(char c) throws IOException {
54 out.append(c);
55 return this;
56 }
57
58 /**
59 * Invokes the delegate's <code>append(CharSequence, int, int)</code> method.
60 * @param csq The character sequence to write
61 * @param start The index of the first character to write
62 * @param end The index of the first character to write (exclusive)
63 * @return this writer
64 * @throws IOException if an I/O error occurs
65 * @since IO 2.0
66 */
67 public Writer append(CharSequence csq, int start, int end) throws IOException {
68 out.append(csq, start, end);
69 return this;
70 }
71
72 /**
73 * Invokes the delegate's <code>append(CharSequence)</code> method.
74 * @param csq The character sequence to write
75 * @return this writer
76 * @throws IOException if an I/O error occurs
77 * @since IO 2.0
78 */
79 public Writer append(CharSequence csq) throws IOException {
80 out.append(csq);
81 return this;
82 }
83
84 /**
85 * Invokes the delegate's <code>write(int)</code> method.
86 * @param idx the character to write
87 * @throws IOException if an I/O error occurs
88 */
89 public void write(int idx) throws IOException {
90 out.write(idx);
91 }
92
93 /**
94 * Invokes the delegate's <code>write(char[])</code> method.
95 * @param chr the characters to write
96 * @throws IOException if an I/O error occurs
97 */
98 public void write(char[] chr) throws IOException {
99 out.write(chr);
100 }
101
102 /**
103 * Invokes the delegate's <code>write(char[], int, int)</code> method.
104 * @param chr the characters to write
105 * @param st The start offset
106 * @param end The number of characters to write
107 * @throws IOException if an I/O error occurs
108 */
109 public void write(char[] chr, int st, int end) throws IOException {
110 out.write(chr, st, end);
111 }
112
113 /**
114 * Invokes the delegate's <code>write(String)</code> method.
115 * @param str the string to write
116 * @throws IOException if an I/O error occurs
117 */
118 public void write(String str) throws IOException {
119 out.write(str);
120 }
121
122 /**
123 * Invokes the delegate's <code>write(String)</code> method.
124 * @param str the string to write
125 * @param st The start offset
126 * @param end The number of characters to write
127 * @throws IOException if an I/O error occurs
128 */
129 public void write(String str, int st, int end) throws IOException {
130 out.write(str, st, end);
131 }
132
133 /**
134 * Invokes the delegate's <code>flush()</code> method.
135 * @throws IOException if an I/O error occurs
136 */
137 public void flush() throws IOException {
138 out.flush();
139 }
140
141 /**
142 * Invokes the delegate's <code>close()</code> method.
143 * @throws IOException if an I/O error occurs
144 */
145 public void close() throws IOException {
146 out.close();
147 }
148
149 }