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Java > Open Source Codes > com > sun > facelets > compiler > AttributeInstruction


1 /**
2  * Licensed under the Common Development and Distribution License,
3  * you may not use this file except in compliance with the License.
4  * You may obtain a copy of the License at
5  *
6  * http://www.sun.com/cddl/
7  *
8  * Unless required by applicable law or agreed to in writing, software
9  * distributed under the License is distributed on an "AS IS" BASIS,
10  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
11  * implied. See the License for the specific language governing
12  * permissions and limitations under the License.
13  */
14
15 package com.sun.facelets.compiler;
16
17
18 import java.io.IOException JavaDoc;
19 import java.util.List JavaDoc;
20
21 import javax.el.ELContext;
22 import javax.el.ELException;
23 import javax.el.ExpressionFactory;
24
25 import javax.faces.context.FacesContext;
26 import javax.faces.context.ResponseWriter;
27
28 import com.sun.facelets.el.ELAdaptor;
29 import com.sun.facelets.el.ELText;
30
31 final class AttributeInstruction implements Instruction {
32     private final String JavaDoc alias;
33
34     private final String JavaDoc attr;
35
36     private final ELText txt;
37     
38
39     public AttributeInstruction(String JavaDoc alias, String JavaDoc attr, ELText txt) {
40         this.alias = alias;
41         this.attr = attr;
42         this.txt = txt;
43     }
44
45     public void write(FacesContext context) throws IOException JavaDoc {
46         ResponseWriter out = context.getResponseWriter();
47         try {
48             ELContext elContext = ELAdaptor.getELContext(context);
49             String JavaDoc val = txt.toString(elContext);
50
51             out.writeAttribute(attr, val, null);
52         } catch (ELException e) {
53             throw new ELException(this.alias + ": " + e.getMessage(), e.getCause());
54         } catch (Exception JavaDoc e) {
55             throw new ELException(this.alias + ": " + e.getMessage(), e);
56         }
57     }
58
59     public Instruction apply(ExpressionFactory factory, ELContext ctx) {
60         ELText nt = this.txt.apply(factory, ctx);
61         if (nt == this.txt) {
62             return this;
63         }
64
65         return new AttributeInstruction(alias, attr, nt);
66     }
67
68     public boolean isLiteral() {
69         return txt.isLiteral();
70     }
71 }
72
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