1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19
20 package org.apache.myfaces.view.facelets.tag.jstl.core;
21
22 import java.io.IOException;
23 import javax.el.ELContext;
24 import javax.el.ELException;
25 import javax.el.ValueExpression;
26 import javax.faces.FacesException;
27 import javax.faces.component.UIComponent;
28 import javax.faces.view.facelets.FaceletContext;
29 import javax.faces.view.facelets.FaceletException;
30 import javax.faces.view.facelets.TagAttribute;
31 import javax.faces.view.facelets.TagConfig;
32 import javax.faces.view.facelets.TagException;
33 import javax.faces.view.facelets.TagHandler;
34 import org.apache.myfaces.view.facelets.AbstractFaceletContext;
35
36 /**
37 * Simplified implementation of c:set
38 *
39 * Sets the result of an expression evaluation in a 'scope'
40 *
41 * NOTE: This implementation is provided for compatibility reasons and
42 * it is considered faulty. It is enabled using
43 * org.apache.myfaces.STRICT_JSF_2_FACELETS_COMPATIBILITY web config param.
44 * Don't use it if EL expression caching is enabled.
45 *
46 * @author Jacob Hookom
47 * @version $Id: SetHandler.java,v 1.2 2008/07/13 19:01:44 rlubke Exp $
48 */
49 //@JSFFaceletTag(name="c:set")
50 public class LegacySetHandler extends TagHandler
51 {
52
53 /**
54 * Name of the exported scoped variable to hold the value
55 * specified in the action. The type of the scoped variable is
56 * whatever type the value expression evaluates to.
57 */
58 //@JSFFaceletAttribute(className="java.lang.String")
59 private final TagAttribute var;
60
61 /**
62 * Expression to be evaluated.
63 */
64 //@JSFFaceletAttribute(
65 // className="javax.el.ValueExpression",
66 // deferredValueType="java.lang.Object")
67 private final TagAttribute value;
68
69 //@JSFFaceletAttribute(
70 // name="scope",
71 // className="java.lang.String",
72 // longDescription="Scope for var.")
73 private final TagAttribute scope;
74
75 //@JSFFaceletAttribute(
76 // name="target",
77 // className="java.lang.String",
78 // longDescription="Target object whose property will be set."+
79 // " Must evaluate to a JavaBeans object with setter property"+
80 // "property, or to a java.util.Map object.")
81 private final TagAttribute target;
82
83 //@JSFFaceletAttribute(
84 // name="property",
85 // className="java.lang.String",
86 // longDescription="Name of the property to be set in the target object.")
87 private final TagAttribute property;
88
89 public LegacySetHandler(TagConfig config)
90 {
91 super(config);
92 this.value = this.getAttribute("value");
93 this.var = this.getAttribute("var");
94 this.scope = this.getAttribute("scope");
95 this.target = this.getAttribute("target");
96 this.property = this.getAttribute("property");
97 }
98
99 @Override
100 public void apply(FaceletContext ctx, UIComponent parent) throws IOException, FacesException, FaceletException,
101 ELException
102 {
103 ValueExpression veObj = this.value.getValueExpression(ctx, Object.class);
104
105 if (this.var != null)
106 {
107 // Get variable name
108 String varStr = this.var.getValue(ctx);
109
110 if (this.scope != null)
111 {
112 String scopeStr = this.scope.getValue(ctx);
113
114 // Check scope string
115 if (scopeStr == null || scopeStr.length() == 0)
116 {
117 throw new TagException(tag, "scope must not be empty");
118 }
119 if ("page".equals(scopeStr))
120 {
121 throw new TagException(tag, "page scope is not allowed");
122 }
123
124 // Build value expression string to set variable
125 StringBuilder expStr = new StringBuilder().append("#{").append(scopeStr);
126 if ("request".equals(scopeStr) || "view".equals(scopeStr) || "session".equals(scopeStr)
127 || "application".equals(scopeStr))
128 {
129 expStr.append("Scope");
130 }
131 expStr.append(".").append(varStr).append("}");
132 ELContext elCtx = ctx.getFacesContext().getELContext();
133 ValueExpression expr = ctx.getExpressionFactory().createValueExpression(
134 elCtx, expStr.toString(), Object.class);
135 expr.setValue(elCtx, veObj.getValue(elCtx));
136 }
137 else
138 {
139 ctx.getVariableMapper().setVariable(varStr, veObj);
140 AbstractFaceletContext actx = ((AbstractFaceletContext) ctx);
141 actx.getPageContext().setAllowCacheELExpressions(false);
142 }
143 }
144 else
145 {
146 // Check attributes
147 if (this.target == null || this.property == null || this.value == null)
148 {
149 throw new TagException(
150 tag, "either attributes var and value or target, property and value must be set");
151 }
152 if (this.target.isLiteral())
153 {
154 throw new TagException(tag, "attribute target must contain a value expression");
155 }
156
157 // Get target object and name of property to set
158 ELContext elCtx = ctx.getFacesContext().getELContext();
159 ValueExpression targetExpr = this.target.getValueExpression(ctx, Object.class);
160 Object targetObj = targetExpr.getValue(elCtx);
161 String propertyName = this.property.getValue(ctx);
162 // Set property on target object
163 ctx.getELResolver().setValue(elCtx, targetObj, propertyName, veObj.getValue(elCtx));
164 }
165 }
166 }