1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.myfaces.custom.stylesheet;
20
21 import org.apache.myfaces.renderkit.html.util.ResourceProvider;
22
23 import javax.servlet.ServletContext;
24 import java.io.ByteArrayInputStream;
25 import java.io.IOException;
26 import java.io.InputStream;
27
28 /**
29 * Allow URLs to return data that is cached by the TextResourceFilter class.
30 * <p>
31 * This implements the Tomahawk ResourceProvider interface which works together
32 * with the Tomahawk AddResourceFactory, ExtensionsFilter and AddResource classes.
33 * The AddResourceFactory can generate a URL which can be embedded in an HTML page.
34 * When invoked, that URL triggers the ExtensionsFilter which invokes AddResource
35 * which then calls back into this class. And this class then retrieves the
36 * requested data from the TextResourceFilter.
37 */
38 public class TextResourceFilterProvider implements ResourceProvider
39 {
40 // Hack note: a slash has to be prefixed to the resource value here because
41 // we are abusing the AddResource API in StylesheetRenderer; see comments
42 // in StylesheetRenderer.encodeEnd for details.
43
44 public boolean exists(ServletContext context, String resource)
45 {
46 resource = "/" + resource; // hack
47 return TextResourceFilter.getInstance(context).getFilteredResource(resource) != null;
48 }
49
50 public int getContentLength(ServletContext context, String resource) throws IOException
51 {
52 resource = "/" + resource; // hack
53 return TextResourceFilter.getInstance(context).getFilteredResource(resource).getSize();
54 }
55
56 public long getLastModified(ServletContext context, String resource) throws IOException
57 {
58 resource = "/" + resource; // hack
59 return TextResourceFilter.getInstance(context).getFilteredResource(resource).getLastModified();
60 }
61
62 public InputStream getInputStream(ServletContext context, String resource) throws IOException
63 {
64 resource = "/" + resource; // hack
65 return new ByteArrayInputStream(
66 TextResourceFilter.getInstance(context).getFilteredResource(resource).getText().getBytes(
67 getEncoding(context, resource)
68 ));
69 }
70
71 public String getEncoding(ServletContext context, String resource) throws IOException
72 {
73 return "UTF-8";
74 }
75 }