01: /*
02: * Copyright 1999-2004 The Apache Software Foundation
03: *
04: * Licensed under the Apache License, Version 2.0 (the "License");
05: * you may not use this file except in compliance with the License.
06: * You may obtain a copy of the License at
07: *
08: * http://www.apache.org/licenses/LICENSE-2.0
09: *
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: package org.apache.commons.chain.web.servlet;
17:
18: import javax.servlet.http.HttpServletRequest;
19: import org.apache.commons.chain.Catalog;
20: import org.apache.commons.chain.Command;
21: import org.apache.commons.chain.Context;
22:
23: /**
24: * <p>{@link Command} that uses the "path info" component of the request URI
25: * to select a {@link Command} from the appropriate {@link Catalog}, and
26: * execute it. To use this command, you would typically map an instance
27: * of {@link ChainProcessor} to a wildcard pattern like "/execute/*" and
28: * then arrange that this is the default command to be executed. In such
29: * an environment, a request for the context-relative URI "/execute/foo"
30: * would cause the "/foo" command to be loaded and executed.</p>
31: *
32: * @author Craig R. McClanahan
33: */
34:
35: public class PathInfoMapper implements Command {
36:
37: // ------------------------------------------------------ Instance Variables
38:
39: private String catalogKey = ChainProcessor.CATALOG_DEFAULT;
40:
41: // -------------------------------------------------------------- Properties
42:
43: /**
44: * <p>Return the context key under which our {@link Catalog} has been
45: * stored.</p>
46: *
47: * @return The context key for the Catalog.
48: */
49: public String getCatalogKey() {
50:
51: return (this .catalogKey);
52:
53: }
54:
55: /**
56: * <p>Set the context key under which our {@link Catalog} has been
57: * stored.</p>
58: *
59: * @param catalogKey The new catalog key
60: */
61: public void setCatalogKey(String catalogKey) {
62:
63: this .catalogKey = catalogKey;
64:
65: }
66:
67: // --------------------------------------------------------- Command Methods
68:
69: /**
70: * <p>Look up the extra path information for this request, and use it to
71: * select an appropriate {@link Command} to be executed.
72: *
73: * @param context Context for the current request
74: * @return The result of executing the Command for the request URI.
75: * @throws Exception if there is a problem executing the Command for
76: * the request URI.
77: */
78: public boolean execute(Context context) throws Exception {
79:
80: // Look up the extra path information for this request
81: ServletWebContext swcontext = (ServletWebContext) context;
82: HttpServletRequest request = swcontext.getRequest();
83: String pathInfo = (String) request
84: .getAttribute("javax.servlet.include.path_info");
85: if (pathInfo == null) {
86: pathInfo = request.getPathInfo();
87: }
88:
89: // Map to the Command specified by the extra path info
90: Catalog catalog = (Catalog) context.get(getCatalogKey());
91: Command command = catalog.getCommand(pathInfo);
92: return (command.execute(context));
93:
94: }
95:
96: }
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