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1
16
17 package org.apache.taglibs.io;
18
19 import java.io.BufferedReader  ;
20 import java.io.IOException ;
21 import java.io.InputStream ;
22 import java.io.InputStreamReader ;
23 import java.io.OutputStream ;
24 import java.io.OutputStreamWriter ;
25 import java.io.Reader ;
26 import java.io.Writer ;
27 import java.net.HttpURLConnection ;
28 import java.net.URL ;
29 import java.net.URLConnection ;
30
31 import javax.servlet.ServletContext ;
32 import javax.servlet.jsp.JspException ;
33 import javax.servlet.jsp.JspWriter ;
34 import javax.servlet.jsp.tagext.BodyContent ;
35 import javax.servlet.jsp.tagext.Tag ;
36
37
42 public class URLTag extends AbstractTag implements PipeProducer, PipeConsumer {
43
44
45 private String url;
46
47
48 private String fullURL;
49
50
51 private String encoding;
52
53
54 private URLConnection connection;
55
56
57 private Writer writer;
58
59
60 private Reader reader;
61
62
63 private byte[] buffer = new byte[ 32*1024 ];
64
65
66 private boolean output = true;
67
68
69 private boolean input = false;
70
71 public URLTag() {
72 }
73
74
75
77 public void addHeader( String name, String value ) throws JspException {
78 if ( TRACE ) {
79 log( "Setting header: " + name + ": " + value );
80 }
81 try {
82 getConnection().setRequestProperty( name, value );
83 }
84 catch (IOException e) {
85 handleException(e);
86 }
87 }
88
89
91 public void addParameter( String name, String value ) {
92 if ( fullURL == null ) {
93 fullURL = url;
94 }
95 String prefix = ( fullURL.indexOf( '?' ) < 0 ) ? "?" : "&";
96 fullURL += prefix + name + "=" + value;
97
98
100 if ( TRACE ) {
101 log( "Adding parameter: " + name + ": " + value );
102 log( "URL is now: " + fullURL );
103 }
104 }
105
106
107 public void setWriter(Writer writer) {
110 this.writer = writer;
111 }
112
113 public void setReader(Reader reader) {
116 this.reader = reader;
117 this.input = true;
118 }
119
120
121 public int doStartTag() throws JspException {
124 fullURL = null;
125 connection = null;
126 return EVAL_BODY_INCLUDE;
127 }
128
129 public int doEndTag() throws JspException {
130 Writer writer = null;
131 try {
132 if ( reader != null ) {
133 writer = getURLWriter();
134 PipeHelper.pipe( reader, writer );
135 reader.close();
136 writer.close();
137 }
138 if ( output ) {
139 readURL();
140 }
141 else {
142 getConnection().connect();
143 }
144 }
145 catch (IOException e) {
146 handleException(e);
147 }
148 finally {
149 if ( writer != null ) {
152 try {
153 writer.close();
154 }
155 catch (Exception e) {
156 }
157 }
158 reader = null;
159 writer = null;
160 }
161 return EVAL_PAGE;
162 }
163
164 public void release() {
165 super.release();
166 url = null;
167 fullURL = null;
168 connection = null;
169 buffer = null;
170 input = false;
171 output = true;
172 reader = null;
173 writer = null;
174 }
175
176
177 public void setUrl(String url) {
180 this.url = url;
181 }
182
183 public void setOutput(boolean output) {
184 this.output = output;
185 }
186
187 public void setInput(boolean input) {
188 this.input = input;
189
190 }
192
193
194 public void setEncoding(String encoding) {
195 this.encoding = encoding;
196 }
197
198 public Writer getURLWriter() throws IOException {
199 OutputStream out = getURLOutputStream();
200 if ( out != null ) {
201 if ( encoding != null ) {
202 return new OutputStreamWriter ( out, encoding );
203 }
204 else {
205 return new OutputStreamWriter ( out );
206 }
207 }
208 return null;
209 }
210
211 public OutputStream getURLOutputStream() throws IOException {
212 URLConnection connection = getConnection();
213 return connection.getOutputStream();
214 }
215
216 public Reader getURLReader() throws IOException {
217 InputStream in = getURLInputStream();
218 if ( in != null ) {
219 if ( encoding != null ) {
220 return new InputStreamReader ( in, encoding );
221 }
222 else {
223 return new InputStreamReader ( in );
224 }
225 }
226 return null;
227 }
228
229 public InputStream getURLInputStream() throws IOException {
230 URLConnection connection = getConnection();
231 connection.connect();
232 return connection.getInputStream();
233 }
234
235
236 protected URLConnection getConnection() throws IOException {
239 if ( connection == null ) {
240 if ( fullURL == null ) {
241 fullURL = url;
242 }
243 URL theURL = URLHelper.createURL(fullURL, pageContext);
244
245 if ( TRACE ) {
246 log( "Reading URL: " + theURL.toString() );
247 }
248
249 connection = theURL.openConnection();
250 configureConnection( connection );
251 }
252 return connection;
253 }
254
255 protected void configureConnection( URLConnection connection ) throws IOException {
256
258 connection.setAllowUserInteraction(false);
259 connection.setDoInput(output);
260 connection.setDoOutput(input);
261 }
262
263 protected void disconnect( URLConnection connection ) {
264 try {
265 if ( connection instanceof HttpURLConnection ) {
266 HttpURLConnection httpConnection = (HttpURLConnection ) connection;
267 httpConnection.disconnect();
268 }
269 }
270 catch (Exception e) {
271 }
273 }
274
275 protected void readURL() throws IOException , JspException {
276 Tag parent = getParent();
277 if ( writer == null && parent instanceof PipeConsumer ) {
278 PipeConsumer consumer = (PipeConsumer) parent;
279 consumer.setReader( getURLReader() );
280 }
281 else {
282 if ( writer == null ) {
283 writer = pageContext.getOut();
284 }
285 Reader reader = getURLReader();
286 try {
287 PipeHelper.pipe( reader, writer );
288 }
289 finally {
290 try {
291 reader.close();
292 }
293 catch (Exception e) {
294 }
295 }
296 }
297 }
298 }
299 |
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