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Java > Open Source Codes > org > apache > tools > ant > taskdefs > optional > ide > VAJToolsServlet


1 /*
2  * Copyright 2001-2004 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
18 package org.apache.tools.ant.taskdefs.optional.ide;
19
20 import com.ibm.ivj.toolserver.servletclasses.servlet.ServletException;
21 import com.ibm.ivj.toolserver.servletclasses.servlet.http.HttpServlet;
22 import com.ibm.ivj.toolserver.servletclasses.servlet.http.HttpServletRequest;
23 import com.ibm.ivj.toolserver.servletclasses.servlet.http.HttpServletResponse;
24 import java.io.IOException JavaDoc;
25 import org.apache.tools.ant.BuildException;
26 import org.apache.tools.ant.util.StringUtils;
27
28 /**
29  * Abstract base class to provide common services for the
30  * VAJ tool API servlets
31  *
32  */
33 public abstract class VAJToolsServlet extends HttpServlet {
34     /**
35      * Adaptation of VAJUtil for servlet context.
36      */
37     class VAJLocalServletUtil extends VAJLocalUtil {
38         public void log(String JavaDoc msg, int level) {
39             try {
40                 if (msg != null) {
41                     msg = msg.replace('\r', ' ');
42                     int i = 0;
43                     while (i < msg.length()) {
44                         int nlPos = msg.indexOf('\n', i);
45                         if (nlPos == -1) {
46                             nlPos = msg.length();
47                         }
48                         response.getWriter().println(Integer.toString(level)
49                                                      + " " + msg.substring(i, nlPos));
50                         i = nlPos + 1;
51                     }
52                 }
53             } catch (IOException JavaDoc e) {
54                 throw new BuildException("logging failed. msg was: "
55                                          + e.getMessage());
56             }
57         }
58     }
59
60     // constants for servlet param names
61 public static final String JavaDoc DIR_PARAM = "dir";
62     public static final String JavaDoc INCLUDE_PARAM = "include";
63     public static final String JavaDoc EXCLUDE_PARAM = "exclude";
64     public static final String JavaDoc CLASSES_PARAM = "cls";
65     public static final String JavaDoc SOURCES_PARAM = "src";
66     public static final String JavaDoc RESOURCES_PARAM = "res";
67     public static final String JavaDoc DEFAULT_EXCLUDES_PARAM = "dex";
68     public static final String JavaDoc PROJECT_NAME_PARAM = "project";
69
70
71     // current request
72 HttpServletRequest request;
73
74     // response to current request
75 HttpServletResponse response;
76
77     // implementation of VAJUtil used by the servlet
78 VAJUtil util;
79
80
81     /**
82      * Execute the request by calling the appropriate
83      * VAJ tool API methods. This method must be implemented
84      * by the concrete servlets
85      */
86     protected abstract void executeRequest();
87
88     /**
89      * Respond to a HTTP request. This method initializes
90      * the servlet and handles errors.
91      * The real work is done in the abstract method executeRequest()
92      */
93     public void doGet(HttpServletRequest req, HttpServletResponse res)
94         throws ServletException, IOException JavaDoc {
95         try {
96             response = res;
97             request = req;
98             initRequest();
99             executeRequest();
100         } catch (BuildException e) {
101             util.log("Error occurred: " + e.getMessage(), VAJUtil.MSG_ERR);
102         } catch (Exception JavaDoc e) {
103             try {
104                 if (!(e instanceof BuildException)) {
105                     String JavaDoc trace = StringUtils.getStackTrace(e);
106                     util.log("Program error in " + this.getClass().getName()
107                              + ":\n" + trace, VAJUtil.MSG_ERR);
108                 }
109             } catch (Throwable JavaDoc t) {
110                 t.printStackTrace();
111             } finally {
112                 if (!(e instanceof BuildException)) {
113                     throw new ServletException(e.getMessage());
114                 }
115             }
116         }
117     }
118
119     /**
120      * initialize the servlet.
121      */
122     protected void initRequest() throws IOException JavaDoc {
123         response.setContentType("text/ascii");
124         if (util == null) {
125             util = new VAJLocalServletUtil();
126         }
127     }
128
129     /**
130      * Get the VAJUtil implementation
131      */
132     VAJUtil getUtil() {
133         return util;
134     }
135
136     /**
137      * Get the boolean value of a parameter.
138      */
139     protected boolean getBooleanParam(String JavaDoc param) {
140         return getBooleanParam(param, false);
141     }
142
143     /**
144      * Get the boolean value of a parameter, with a default value if
145      * the parameter hasn't been passed to the servlet.
146      */
147     protected boolean getBooleanParam(String JavaDoc param, boolean defaultValue) {
148         String JavaDoc value = getFirstParamValueString(param);
149         if (value != null) {
150             return toBoolean(value);
151         } else {
152             return defaultValue;
153         }
154     }
155
156     /**
157      * Returns the first encountered value for a parameter.
158      */
159     protected String JavaDoc getFirstParamValueString(String JavaDoc param) {
160         String JavaDoc[] paramValuesArray = request.getParameterValues(param);
161         if (paramValuesArray == null) {
162             return null;
163         }
164         return paramValuesArray[0];
165     }
166
167     /**
168      * Returns all values for a parameter.
169      */
170     protected String JavaDoc[] getParamValues(String JavaDoc param) {
171         return request.getParameterValues(param);
172     }
173
174     /**
175      * A utility method to translate the strings "yes", "true", and "ok"
176      * to boolean true, and everything else to false.
177      */
178     protected boolean toBoolean(String JavaDoc string) {
179         String JavaDoc lower = string.toLowerCase();
180         return (lower.equals("yes") || lower.equals("true") || lower.equals("ok"));
181     }
182 }
183
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