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1 /* This software is published under the terms of the OpenSymphony Software
2 * License version 1.1, of which a copy has been included with this
3 * distribution in the LICENSE.txt file. */
4 package com.opensymphony.module.sitemesh.filter;
5
6 import javax.servlet.ServletOutputStream;
7 import java.io.IOException;
8
9 /**
10 * Provides a ServletOutputStream that routes through to another ServletOutputStream, however the destination
11 * can be changed at any point. The destination can be passed in using a factory, so it will not be created
12 * until it's actually needed.
13 *
14 * @author Joe Walnes
15 * @version $Revision: 1.1 $
16 */
17 public class RoutableServletOutputStream extends ServletOutputStream {
18
19 private ServletOutputStream destination;
20 private DestinationFactory factory;
21
22 /**
23 * Factory to lazily instantiate the destination.
24 */
25 public static interface DestinationFactory {
26 ServletOutputStream create() throws IOException;
27 }
28
29 public RoutableServletOutputStream(DestinationFactory factory) {
30 this.factory = factory;
31 }
32
33 private ServletOutputStream getDestination() throws IOException {
34 if (destination == null) {
35 destination = factory.create();
36 }
37 return destination;
38 }
39
40 public void updateDestination(DestinationFactory factory) {
41 destination = null;
42 this.factory = factory;
43 }
44
45 public void close() throws IOException {
46 getDestination().close();
47 }
48
49 public void write(int b) throws IOException {
50 getDestination().write(b);
51 }
52
53 public void print(String s) throws IOException {
54 getDestination().print(s);
55 }
56
57 public void print(boolean b) throws IOException {
58 getDestination().print(b);
59 }
60
61 public void print(char c) throws IOException {
62 getDestination().print(c);
63 }
64
65 public void print(int i) throws IOException {
66 getDestination().print(i);
67 }
68
69 public void print(long l) throws IOException {
70 getDestination().print(l);
71 }
72
73 public void print(float v) throws IOException {
74 getDestination().print(v);
75 }
76
77 public void print(double v) throws IOException {
78 getDestination().print(v);
79 }
80
81 public void println() throws IOException {
82 getDestination().println();
83 }
84
85 public void println(String s) throws IOException {
86 getDestination().println(s);
87 }
88
89 public void println(boolean b) throws IOException {
90 getDestination().println(b);
91 }
92
93 public void println(char c) throws IOException {
94 getDestination().println(c);
95 }
96
97 public void println(int i) throws IOException {
98 getDestination().println(i);
99 }
100
101 public void println(long l) throws IOException {
102 getDestination().println(l);
103 }
104
105 public void println(float v) throws IOException {
106 getDestination().println(v);
107 }
108
109 public void println(double v) throws IOException {
110 getDestination().println(v);
111 }
112
113 public void write(byte b[]) throws IOException {
114 getDestination().write(b);
115 }
116
117 public void write(byte b[], int off, int len) throws IOException {
118 getDestination().write(b, off, len);
119 }
120
121 public void flush() throws IOException {
122 getDestination().flush();
123 }
124 }