1 /* 2 * Copyright (c) 1999, 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. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 25 /** 26 * Plain text file handler 27 * 28 * This class provides an example of a a replacement content handler for 29 * the text/plain content type. It reads the content of the URL, and prepends 30 * an additional message at the beginning. 31 * 32 * Note that the only restrictions on the package/class names are: 33 * 1) the package must end in the major type of the content type (such as 34 * text, image, application, etc). 35 * 2) the class name must be named with the subtype of the content type (for 36 * content type "text/plain", this would be "plain" as in this example; for 37 * content type "image/gif", the class name would be "gif", and the package 38 * name must end with ".image". 39 * 3) the class must be a subclass of ContentHandler. 40 * 4) It must define the getContent function. 41 */ 42 package COM.foo.content.text; 43 44 import java.net.ContentHandler; 45 import java.io.InputStream; 46 import java.net.URLConnection; 47 import java.io.IOException; 48 49 public class plain extends ContentHandler { 50 /** 51 * Returns one of several object types (this set may change in future 52 * versions): 53 * 1) instance of Thread: 54 * Invoke the thread to launch an external viewer. 55 * 2) instance of InputStream: 56 * Bring up the "Save to disk" dialog page to allow the content 57 * to be saved to disk. 58 * 3) instance of InputStreamImageSource: 59 * Load the image into HotJava in an image viewer page. 60 * 4) instance of String: 61 * Go to a new page with the string as the plain text content 62 * of that page. 63 */ getContent(URLConnection uc)64 public Object getContent(URLConnection uc) { 65 try { 66 InputStream is = uc.getInputStream(); 67 StringBuffer sb = new StringBuffer(); 68 int c; 69 70 sb.append("[Content of " + uc.getURL() + "]\n\n"); 71 sb.append("[This opening message brought to you by your plain/text\n"); 72 sb.append("content handler. To remove this content handler, delete the\n"); 73 sb.append("COM.foo.content.text directory from your class path and\n"); 74 sb.append("the java.content.handler.pkgs property from your HotJava\n"); 75 sb.append("properties file.]\n"); 76 sb.append("----------------------------------------------------------------\n\n"); 77 78 // Read the characters from the source, accumulate them into the string buffer. 79 // (Not the most efficient, but simplest for this example.) 80 while ((c = is.read()) >= 0) { 81 sb.append((char)c); 82 } 83 84 // Tidy up 85 is.close(); 86 87 // Return the resulting string to our client (we're case 4 above) 88 return sb.toString(); 89 } catch (IOException e) { 90 // For any exception, just return an indication of what went wrong. 91 return "Problem reading document: " + uc.getURL(); 92 } 93 } 94 } 95