1 /*
2 * Copyright 2008 University Corporation for Advanced Internet Development, Inc.
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.opensaml.util.resource;
18
19 import java.io.InputStream;
20
21 import org.slf4j.Logger;
22 import org.slf4j.LoggerFactory;
23
24 /** A {@link Resource} whose contents may be run through a filter as it is being read. */
25 public abstract class AbstractFilteredResource implements Resource {
26
27 /** Class logger. */
28 private final Logger log = LoggerFactory.getLogger(AbstractFilteredResource.class);
29
30 /** Associated resource filter. */
31 private ResourceFilter resourceFilter;
32
33 /** Constructor. */
34 protected AbstractFilteredResource() {
35
36 }
37
38 /**
39 * Constructor.
40 *
41 * @param filter the filter used on the resource
42 *
43 * @deprecated use {@link #setResourceFilter(ResourceFilter)} instead
44 */
45 protected AbstractFilteredResource(ResourceFilter filter) {
46 resourceFilter = filter;
47 }
48
49 /**
50 * Gets the resource filter associated with this resource.
51 *
52 * @return resource filter associated with this resource
53 */
54 public ResourceFilter getResourceFilter() {
55 return resourceFilter;
56 }
57
58 /**
59 * Sets the resource filter associated with this resource.
60 *
61 * @param filter filter associated with this resource
62 */
63 public void setResourceFilter(ResourceFilter filter){
64 resourceFilter = filter;
65 }
66
67 /**
68 * Applies the filter to the given stream resulting in the returned stream. If no filter is set than the given
69 * stream is the returned stream.
70 *
71 * @param stream the stream to filter
72 *
73 * @return the filtered stream
74 *
75 * @throws ResourceException thrown if the filter can not be applied to the stream
76 */
77 protected InputStream applyFilter(InputStream stream) throws ResourceException {
78 ResourceFilter filter = getResourceFilter();
79 if (filter != null) {
80 log.debug("Apply filter '{}' to resource '{}'", filter.getClass(), this.getLocation());
81 return getResourceFilter().applyFilter(stream);
82 } else {
83 return stream;
84 }
85 }
86 }