|
1 package org.sapia.gumby.tags;
2
3 import org.sapia.gumby.RenderContext;
4 import org.sapia.gumby.factory.ContextAware;
5 import org.sapia.util.xml.confix.ConfigurationException;
6 import org.sapia.util.xml.confix.ObjectCreationCallback;
7
8
23 public class Constant implements ObjectCreationCallback, ContextAware {
24
25 private String  _name;
26 private RenderContext _context;
27
28 public void setName(String name) {
29 _name = name;
30 }
31
32 public void handleContext(RenderContext ctx) {
33 _context = ctx;
34 }
35
36
39 public Object onCreate() throws ConfigurationException {
40 if(_name == null) {
41 throw new ConfigurationException("Constant name not specified");
42 }
43 int i = _name.lastIndexOf('.');
44 if(i < 0) {
45 throw new ConfigurationException("Invalid name for constant: " + _name
46 + "; expecting format: some.class.Name.Constant");
47 }
48 String className = _name.substring(0, i);
49 Class clazz = _context.getSettings().resolveClass(className);
50 if(clazz == null) {
51 throw new ConfigurationException("Could not resolve class: " + className);
52 }
53 try {
54 return clazz.getField(_name.substring(i + 1)).get(null);
55 } catch(NoSuchFieldException e) {
56 throw new ConfigurationException("Unkown constant: "
57 + _name.substring(i + 1) + " for class " + className);
58 } catch(IllegalAccessException e) {
59 throw new ConfigurationException("Constant not public: "
60 + _name.substring(i + 1) + " for class " + className);
61 }
62 }
63
64 }
65 |
Popular Tags |
Java API By Example, From Geeks To Geeks.