author | prappo |
Fri, 10 Jul 2015 16:40:12 +0100 | |
changeset 31642 | 7ae76e376fcd |
parent 25859 | 3317bb8137f4 |
child 32227 | 34721a47bc92 |
permissions | -rw-r--r-- |
2 | 1 |
/* |
19069 | 2 |
* Copyright (c) 1995, 2013, Oracle and/or its affiliates. All rights reserved. |
2 | 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 |
|
5506 | 7 |
* published by the Free Software Foundation. Oracle designates this |
2 | 8 |
* particular file as subject to the "Classpath" exception as provided |
5506 | 9 |
* by Oracle in the LICENSE file that accompanied this code. |
2 | 10 |
* |
11 |
* This code is distributed in the hope that it will be useful, but WITHOUT |
|
12 |
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
|
13 |
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
|
14 |
* version 2 for more details (a copy is included in the LICENSE file that |
|
15 |
* accompanied this code). |
|
16 |
* |
|
17 |
* You should have received a copy of the GNU General Public License version |
|
18 |
* 2 along with this work; if not, write to the Free Software Foundation, |
|
19 |
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
|
20 |
* |
|
5506 | 21 |
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
22 |
* or visit www.oracle.com if you need additional information or have any |
|
23 |
* questions. |
|
2 | 24 |
*/ |
25 |
||
26 |
package java.net; |
|
27 |
||
28 |
import java.io.IOException; |
|
29 |
||
30 |
/** |
|
19069 | 31 |
* The abstract class {@code ContentHandler} is the superclass |
32 |
* of all classes that read an {@code Object} from a |
|
33 |
* {@code URLConnection}. |
|
2 | 34 |
* <p> |
35 |
* An application does not generally call the |
|
19069 | 36 |
* {@code getContent} method in this class directly. Instead, an |
37 |
* application calls the {@code getContent} method in class |
|
38 |
* {@code URL} or in {@code URLConnection}. |
|
2 | 39 |
* The application's content handler factory (an instance of a class that |
19069 | 40 |
* implements the interface {@code ContentHandlerFactory} set |
41 |
* up by a call to {@code setContentHandler}) is |
|
42 |
* called with a {@code String} giving the MIME type of the |
|
2 | 43 |
* object being received on the socket. The factory returns an |
19069 | 44 |
* instance of a subclass of {@code ContentHandler}, and its |
45 |
* {@code getContent} method is called to create the object. |
|
2 | 46 |
* <p> |
31642
7ae76e376fcd
8064925: URLConnection::getContent needs to be updated to work with modules
prappo
parents:
25859
diff
changeset
|
47 |
* If no content handler could be {@linkplain URLConnection#getContent() found}, |
7ae76e376fcd
8064925: URLConnection::getContent needs to be updated to work with modules
prappo
parents:
25859
diff
changeset
|
48 |
* URLConnection will look for a content handler in a user-definable set of places. |
24260
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
49 |
* Users can define a vertical-bar delimited set of class prefixes |
31642
7ae76e376fcd
8064925: URLConnection::getContent needs to be updated to work with modules
prappo
parents:
25859
diff
changeset
|
50 |
* to search through by defining the <i>{@value java.net.URLConnection#contentPathProp}</i> |
24260
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
51 |
* property. The class name must be of the form: |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
52 |
* <blockquote> |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
53 |
* <i>{package-prefix}.{major}.{minor}</i> |
31642
7ae76e376fcd
8064925: URLConnection::getContent needs to be updated to work with modules
prappo
parents:
25859
diff
changeset
|
54 |
* <p> |
24260
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
55 |
* where <i>{major}.{minor}</i> is formed by taking the |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
56 |
* content-type string, replacing all slash characters with a |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
57 |
* {@code period} ('.'), and all other non-alphanumeric characters |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
58 |
* with the underscore character '{@code _}'. The alphanumeric |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
59 |
* characters are specifically the 26 uppercase ASCII letters |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
60 |
* '{@code A}' through '{@code Z}', the 26 lowercase ASCII |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
61 |
* letters '{@code a}' through '{@code z}', and the 10 ASCII |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
62 |
* digits '{@code 0}' through '{@code 9}'. |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
63 |
* <p> |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
64 |
* e.g. |
2 | 65 |
* YoyoDyne.experimental.text.plain |
24260
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
66 |
* </blockquote> |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
67 |
* If no user-defined content handler is found, then the system |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
68 |
* tries to load a specific <i>content-type</i> handler from one |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
69 |
* of the built-in handlers, if one exists. |
55a72a7e0cf9
8039470: java.net Content Handler API incorrectly specifies implementation specific location of handler classes
chegar
parents:
20754
diff
changeset
|
70 |
* <p> |
2 | 71 |
* If the loading of the content handler class would be performed by |
72 |
* a classloader that is outside of the delegation chain of the caller, |
|
73 |
* the JVM will need the RuntimePermission "getClassLoader". |
|
74 |
* |
|
75 |
* @author James Gosling |
|
76 |
* @see java.net.ContentHandler#getContent(java.net.URLConnection) |
|
77 |
* @see java.net.ContentHandlerFactory |
|
78 |
* @see java.net.URL#getContent() |
|
79 |
* @see java.net.URLConnection |
|
80 |
* @see java.net.URLConnection#getContent() |
|
81 |
* @see java.net.URLConnection#setContentHandlerFactory(java.net.ContentHandlerFactory) |
|
24865
09b1d992ca72
8044740: Convert all JDK versions used in @since tag to 1.n[.n] in jdk repo
henryjen
parents:
24260
diff
changeset
|
82 |
* @since 1.0 |
2 | 83 |
*/ |
84 |
abstract public class ContentHandler { |
|
31642
7ae76e376fcd
8064925: URLConnection::getContent needs to be updated to work with modules
prappo
parents:
25859
diff
changeset
|
85 |
|
2 | 86 |
/** |
87 |
* Given a URL connect stream positioned at the beginning of the |
|
88 |
* representation of an object, this method reads that stream and |
|
89 |
* creates an object from it. |
|
90 |
* |
|
91 |
* @param urlc a URL connection. |
|
19069 | 92 |
* @return the object read by the {@code ContentHandler}. |
2 | 93 |
* @exception IOException if an I/O error occurs while reading the object. |
94 |
*/ |
|
95 |
abstract public Object getContent(URLConnection urlc) throws IOException; |
|
96 |
||
97 |
/** |
|
98 |
* Given a URL connect stream positioned at the beginning of the |
|
99 |
* representation of an object, this method reads that stream and |
|
100 |
* creates an object that matches one of the types specified. |
|
101 |
* |
|
102 |
* The default implementation of this method should call getContent() |
|
103 |
* and screen the return type for a match of the suggested types. |
|
104 |
* |
|
105 |
* @param urlc a URL connection. |
|
106 |
* @param classes an array of types requested |
|
19069 | 107 |
* @return the object read by the {@code ContentHandler} that is |
31642
7ae76e376fcd
8064925: URLConnection::getContent needs to be updated to work with modules
prappo
parents:
25859
diff
changeset
|
108 |
* the first match of the suggested types or |
7ae76e376fcd
8064925: URLConnection::getContent needs to be updated to work with modules
prappo
parents:
25859
diff
changeset
|
109 |
* {@code null} if none of the requested are supported. |
2 | 110 |
* @exception IOException if an I/O error occurs while reading the object. |
111 |
* @since 1.3 |
|
112 |
*/ |
|
20754
3d7b2fafc34b
8025967: addition of -Werror broke the old build
valeriep
parents:
19069
diff
changeset
|
113 |
@SuppressWarnings("rawtypes") |
11362
02eae572563e
7125055: ContentHandler.getContent API changed in error
chegar
parents:
10596
diff
changeset
|
114 |
public Object getContent(URLConnection urlc, Class[] classes) throws IOException { |
2 | 115 |
Object obj = getContent(urlc); |
116 |
||
31642
7ae76e376fcd
8064925: URLConnection::getContent needs to be updated to work with modules
prappo
parents:
25859
diff
changeset
|
117 |
for (Class<?> c : classes) { |
7ae76e376fcd
8064925: URLConnection::getContent needs to be updated to work with modules
prappo
parents:
25859
diff
changeset
|
118 |
if (c.isInstance(obj)) { |
2 | 119 |
return obj; |
31642
7ae76e376fcd
8064925: URLConnection::getContent needs to be updated to work with modules
prappo
parents:
25859
diff
changeset
|
120 |
} |
2 | 121 |
} |
122 |
return null; |
|
123 |
} |
|
124 |
} |