1 /* 2 * Copyright 1999,2004 The Apache Software Foundation. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package org.apache.commons.feedparser.locate; 18 19 import java.util.regex.Pattern; 20 21 /** 22 * <p> 23 * A FeedReference is used within the RSS/Atom location facility to pass back 24 * metadata for feed discoveries. 25 * 26 * <p> 27 * Right now we pass back the URL to the feeds as the `resource' parameter. The 28 * media type (application/rss+xml, application/atom+xml, etc) as the type param 29 * (which is optional). We also pass back the `title' back if its specified 30 * within autodiscovery. This will be null if another discovery method is used. 31 * 32 * <p> Its important to realize that the media type is only given if we're 100% 33 * certain of the value. If we have to use probe discovery or link discovery it 34 * might not be possible to obtain the media type without antoher network 35 * request (via HTTP headers). 36 * 37 * <p> Note that internally (within the ProbeLocator) we don't use absolute 38 * resource URLs but use relative ones and use the media type as the default 39 * media type. 40 * 41 * @author <a href="mailto:burton@apache.org">Kevin A. Burton</a> 42 */ 43 public class FeedReference { 44 45 public static final String ATOM_MEDIA_TYPE = "application/atom+xml"; 46 public static final String RSS_MEDIA_TYPE = "application/rss+xml"; 47 public static final String XML_MEDIA_TYPE = "text/xml"; 48 49 public static int METHOD_AUTO_DISCOVERY = 1; 50 public static int METHOD_PROBE_DISCOVERY = 2; 51 public static int METHOD_LINK_DISCOVERY = 4; 52 53 /** 54 * The network addressable resource forfor this feed. 55 */ 56 public String resource = null; 57 58 /** 59 * The media type of this feed. 60 */ 61 public String type = null; 62 63 /** 64 * The title of the reference. Usually FOAF, RSS or Atom per auto-discovery 65 * link. 66 */ 67 public String title = null; 68 69 /** 70 * The method of discovery... 71 */ 72 public int method = 0; 73 74 protected Pattern schemePattern = Pattern.compile("^[^:/]*:/.*$"); 75 76 public FeedReference( String resource, String type ) { 77 this.resource = resource; 78 this.type = type; 79 } 80 81 public String toString() { 82 return resource; 83 } 84 85 public boolean equals(Object obj) { 86 if (obj == null || (obj instanceof FeedReference) == false) 87 return false; 88 89 FeedReference compareMe = (FeedReference)obj; 90 91 if (resource.equals(compareMe.resource)) { 92 //ignore title and type when doing equality 93 return true; 94 } 95 96 return false; 97 } 98 99 /** Determines if the resource given by this FeedReference is relative. 100 * For example, the resource could be '/atom.xml', which is relative. 101 * It could also be 102 * "http://rss.groups.yahoo.com/group/talkinaboutarchitecture/rss". 103 */ 104 public boolean isRelative() { 105 if (resource == null) 106 return true; 107 108 // look for a scheme:/ 109 return !schemePattern.matcher(resource).matches(); 110 111 } 112 113 }