/[projects]/WebConfig/src/dk/thoerup/webconfig/ConfigServlet.java
ViewVC logotype

Annotation of /WebConfig/src/dk/thoerup/webconfig/ConfigServlet.java

Parent Directory Parent Directory | Revision Log Revision Log


Revision 1321 - (hide annotations) (download)
Tue Apr 19 20:29:52 2011 UTC (13 years, 1 month ago) by torben
File size: 4012 byte(s)
Just send http 500 errors instead of throwing an exception
1 torben 1319 package dk.thoerup.webconfig;
2    
3     import java.io.IOException;
4     import java.lang.annotation.Annotation;
5     import java.lang.reflect.Field;
6    
7     import javax.servlet.ServletException;
8     import javax.servlet.http.HttpServlet;
9     import javax.servlet.http.HttpServletRequest;
10     import javax.servlet.http.HttpServletResponse;
11    
12     public class ConfigServlet extends HttpServlet {
13     private static final long serialVersionUID = 1L;
14    
15     private Object configObject;
16    
17     public void setConfigObject(Object obj) {
18     configObject = obj;
19     }
20    
21    
22     @Override
23     public void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
24    
25    
26     resp.setDateHeader("Expires", 0);
27     resp.setHeader("Pragma", "no-cache");
28     resp.setHeader("Cache-Control", "no-cache");
29     resp.setContentType("text/html");
30    
31     StringBuilder sb = new StringBuilder();
32    
33     sb.append("<html><body><h3>WebConfig:</h3><table border='1' cellspacing='0'>");
34     sb.append("<tr><th>Field name</th><th>Type</th><th>Description</th><th>Value</th><th>&nbsp;</th></tr>\n");
35    
36    
37     Field fields[] = configObject.getClass().getDeclaredFields();
38    
39     try {
40     for(Field field : fields) {
41     field.setAccessible(true);
42    
43     ConfigVariable anno = field.getAnnotation(ConfigVariable.class);
44     if (anno == null)
45     continue;
46    
47     sb.append("<tr>");
48     sb.append("<td>").append( field.getName() ).append("</td>");
49     sb.append("<td>").append( field.getType().getName() ).append("</td>");
50     sb.append("<td>").append( anno.description() ).append("&nbsp;</td>");
51    
52     sb.append("<form action='").append( req.getRequestURI() ).append("' method='post'>");
53     sb.append("<td><input type='text' name='varvalue' value='").append( ""+ field.get(configObject) ).append("' /></td>");
54     sb.append("<input type='hidden' name='varname' value='").append( field.getName() ).append("' />");
55    
56     if (anno.readonly() == false)
57     sb.append("<td><input type='submit' name='Set' value='Set'></td>\n");
58     else
59     sb.append("<td>&nbsp;</td>");
60    
61     sb.append("</form></tr>\n");
62    
63    
64    
65    
66     field.getType().getName();
67     }
68     } catch (IllegalAccessException e) {
69     throw new ServletException(e);
70     }
71    
72     sb.append("</table></body></html>");
73    
74     resp.getWriter().print( sb.toString() );
75     }
76    
77     @Override
78     protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
79     String name = req.getParameter("varname");
80     String value = req.getParameter("varvalue");
81    
82     try {
83     Field field = configObject.getClass().getDeclaredField(name);
84     field.setAccessible(true);
85     ConfigVariable anno = field.getAnnotation(ConfigVariable.class);
86    
87 torben 1321 if (anno == null) {
88     resp.sendError(500, "Field is not annotated");
89     return;
90     }
91 torben 1319
92 torben 1321 if (anno.readonly() == true) {
93     resp.sendError(500, "Can't write a read-only field");
94     return;
95     }
96    
97 torben 1319
98    
99     if (field.getType().getName().equals("int") ) {
100     field.setInt(configObject, Integer.parseInt(value) );
101     } else if (field.getType().getName().equals("boolean") ) {
102     field.setBoolean(configObject, Boolean.parseBoolean(value) );
103     } else if (field.getType().getName().equals("long") ) {
104     field.setLong(configObject, Long.parseLong(value) );
105     } else if (field.getType().getName().equals("short") ) {
106     field.setShort(configObject, Short.parseShort(value) );
107     } else if (field.getType().getName().equals("double") ) {
108     field.setDouble(configObject, Double.parseDouble(value) );
109     } else if (field.getType().getName().equals("float") ) {
110     field.setFloat(configObject, Float.parseFloat(value) );
111     } else if (field.getType().getName().equals("char") ) {
112     field.setFloat(configObject, value.charAt(0) );
113     } else {
114     field.set(configObject, value );
115     }
116    
117    
118     } catch (NoSuchFieldException e) {
119 torben 1321 resp.sendError(500, "No such field: " + name);
120 torben 1319 } catch (IllegalAccessException e) { //this can't happen
121     throw new ServletException(e);
122     }
123    
124     resp.sendRedirect( req.getRequestURI() );
125     }
126    
127     }

  ViewVC Help
Powered by ViewVC 1.1.20