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1
9
10 package org.jboss.portal.format.template;
11
12 import java.io.IOException  ;
13 import java.lang.reflect.Constructor ;
14 import java.util.Collection ;
15 import java.util.Collections ;
16 import java.util.HashMap ;
17 import java.util.Map ;
18 import java.util.Set ;
19
20 import javassist.CannotCompileException;
21 import javassist.CtClass;
22
23 import org.apache.log4j.Logger;
24 import org.dom4j.Document;
25 import org.dom4j.Element;
26
27
30 public class TemplateRepository
31 {
32
33
34 private final Logger log = Logger.getLogger(getClass());
35
36
37 private Map templates = new HashMap ();
38
39
40 private Map classes = new HashMap ();
41
42
43 private TemplateClassLoader tcl = new TemplateClassLoader(Thread.currentThread().getContextClassLoader());
44
45 public TemplateRepository()
46 {
47 }
48
49 public Template createTemplate(String name)
50 {
51 return createTemplate(name, Context.NULL_CONTEXT);
52 }
53
54
60 public Template createTemplate(String name, Context ctx)
61 {
62 Template template = null;
63 try
64 {
65 Class clazz = (Class )classes.get(name);
66 if (clazz != null)
67 {
68 Constructor ctor = clazz.getConstructor(new Class []{Context.class});
69 template = (Template)ctor.newInstance(new Object []{ctx});
70 }
71 else
72 {
73 log.warn("Template " + name + " not found");
74 }
75 }
76 catch(Exception e)
77 {
78 log.error("Cannot instantiate template " + name, e);
79 throw new RuntimeException ("An unexpected exception occured during the template instantiation");
80 }
81 return template;
82 }
83
84 public void addTemplate(String name, Document doc) throws BuildException
85 {
86 addTemplate(name, doc, Collections.EMPTY_SET);
87 }
88
89 public void addTemplate(String name, Element node) throws BuildException
90 {
91 addTemplate(name, node, Collections.EMPTY_SET);
92 }
93
94 public void addTemplate(String name, Document doc, Set names) throws BuildException
95 {
96 addTemplate(name, doc.getRootElement(), names);
97 }
98
99 public void addTemplate(String name, Element node, Set names) throws BuildException
100 {
101 templates.put(name, node);
103 log.debug("Loaded template " + name);
104
105 Class clazz = generate(node, names);
107 log.debug("Template " + name + " generated " + clazz.getName());
108
109 classes.put(name, clazz);
111 }
112
113 private Class generate(Element node, Set names) throws BuildException
114 {
115 try
116 {
117 String className = tcl.addTemplate(node, names);
119
120 return tcl.loadClass(className);
122 }
123 catch(ClassNotFoundException e)
124 {
125 throw new BuildException("Unexpected error, cannot compile template", e);
126 }
127 }
128
129 public void clear()
130 {
131 classes.clear();
132 templates.clear();
133 tcl = new TemplateClassLoader(Thread.currentThread().getContextClassLoader());
134 }
135
136 public static class TemplateClassLoader extends ClassLoader
137 {
138
139 private final Map classes;
140
141 public TemplateClassLoader(ClassLoader parent)
142 {
143 super(parent);
144 this.classes = new HashMap ();
145 }
146
147 public String addTemplate(Document doc, Set names) throws BuildException
148 {
149 return addTemplate(doc.getRootElement(), names);
150 }
151
152 public String addTemplate(Element node, Set names) throws BuildException
153 {
154 try
155 {
156 TemplateBuilder builder = new TemplateBuilder(node, names);
157 builder.build();
158 CtClass cc = builder.getGeneratedClass();
159 classes.put(cc.getName(), cc.toBytecode());
160 return cc.getName();
161 }
162 catch(IOException e)
163 {
164 throw new BuildException("Unexpected error cannot compile template", e);
165 }
166 catch(CannotCompileException e)
167 {
168 throw new BuildException("Unexpected error cannot compile template", e);
169 }
170 }
171
172 public Collection getClassNames()
173 {
174 return Collections.unmodifiableCollection(classes.keySet());
175 }
176
177 protected Class findClass(String name) throws ClassNotFoundException
178 {
179 byte[] bytes = (byte[])classes.get(name);
180 if (bytes == null)
181 {
182 throw new ClassNotFoundException ("Class " + name + " does not exists");
183 }
184 return defineClass(name, bytes, 0, bytes.length);
185 }
186 }
187 }
188 |
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