001/*
002 * (C) Copyright 2007 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     Nuxeo - initial API and implementation
018 *
019 * $Id: GenericValueHolderRule.java 28456 2008-01-03 12:01:11Z sfermigier $
020 */
021
022package org.nuxeo.ecm.platform.ui.web.tag.jsf;
023
024import javax.el.MethodExpression;
025import javax.el.ValueExpression;
026import javax.faces.component.UIComponent;
027import javax.faces.component.ValueHolder;
028import javax.faces.convert.Converter;
029import javax.faces.view.facelets.FaceletContext;
030import javax.faces.view.facelets.MetaRule;
031import javax.faces.view.facelets.Metadata;
032import javax.faces.view.facelets.MetadataTarget;
033import javax.faces.view.facelets.TagAttribute;
034
035import org.nuxeo.ecm.platform.ui.web.binding.MethodValueExpression;
036import org.nuxeo.ecm.platform.ui.web.util.ComponentTagUtils;
037
038import com.sun.faces.facelets.el.LegacyValueBinding;
039
040/**
041 * Generic value rule, used to evaluate an expression as a regular value expression, or invoking a method expression.
042 * <p>
043 * The method can have parameters and the expression must use parentheses even if no parameters are needed.
044 *
045 * @author <a href="mailto:at@nuxeo.com">Anahide Tchertchian</a>
046 * @deprecated since 5.7.3: resolving method expressions for value expressions is now supported by the default EL, this
047 *             is now useless
048 */
049@Deprecated
050public class GenericValueHolderRule extends MetaRule {
051
052    static final class LiteralConverterMetadata extends Metadata {
053
054        private final String converterId;
055
056        LiteralConverterMetadata(String converterId) {
057            this.converterId = converterId;
058        }
059
060        @Override
061        public void applyMetadata(FaceletContext ctx, Object instance) {
062            ((ValueHolder) instance).setConverter(ctx.getFacesContext().getApplication().createConverter(converterId));
063        }
064    }
065
066    static final class DynamicConverterMetadata2 extends Metadata {
067
068        private final TagAttribute attr;
069
070        DynamicConverterMetadata2(TagAttribute attr) {
071            this.attr = attr;
072        }
073
074        @Override
075        public void applyMetadata(FaceletContext ctx, Object instance) {
076            ((UIComponent) instance).setValueExpression("converter", attr.getValueExpression(ctx, Converter.class));
077        }
078    }
079
080    static final class LiteralValueMetadata extends Metadata {
081
082        private final String value;
083
084        LiteralValueMetadata(String value) {
085            this.value = value;
086        }
087
088        @Override
089        public void applyMetadata(FaceletContext ctx, Object instance) {
090            ((ValueHolder) instance).setValue(value);
091        }
092    }
093
094    static final class DynamicValueExpressionMetadata extends Metadata {
095
096        private final TagAttribute attr;
097
098        DynamicValueExpressionMetadata(TagAttribute attr) {
099            this.attr = attr;
100        }
101
102        @Override
103        public void applyMetadata(FaceletContext ctx, Object instance) {
104            ((UIComponent) instance).setValueExpression("value", attr.getValueExpression(ctx, Object.class));
105        }
106    }
107
108    static final class MethodValueBindingMetadata extends Metadata {
109
110        private final TagAttribute attr;
111
112        MethodValueBindingMetadata(TagAttribute attr) {
113            this.attr = attr;
114        }
115
116        @Override
117        public void applyMetadata(FaceletContext ctx, Object instance) {
118            Class[] paramTypesClasses = new Class[0];
119            Class returnType = Object.class;
120            MethodExpression meth = attr.getMethodExpression(ctx, returnType, paramTypesClasses);
121            ValueExpression ve = new MethodValueExpression(ctx.getFunctionMapper(), ctx.getVariableMapper(), meth,
122                    paramTypesClasses);
123            ((UIComponent) instance).setValueBinding("value", new LegacyValueBinding(ve));
124        }
125    }
126
127    public static final GenericValueHolderRule Instance = new GenericValueHolderRule();
128
129    @Override
130    public Metadata applyRule(String name, TagAttribute attribute, MetadataTarget meta) {
131        if (meta.isTargetInstanceOf(ValueHolder.class)) {
132
133            if ("converter".equals(name)) {
134                if (attribute.isLiteral()) {
135                    return new LiteralConverterMetadata(attribute.getValue());
136                } else {
137                    return new DynamicConverterMetadata2(attribute);
138                }
139            }
140
141            if ("genericValue".equals(name)) {
142                if (attribute.isLiteral()) {
143                    return new LiteralValueMetadata(attribute.getValue());
144                } else {
145                    String value = attribute.getValue();
146                    if (ComponentTagUtils.isMethodReference(value)) {
147                        // value expression resolved invoking a method
148                        // expression
149                        return new MethodValueBindingMetadata(attribute);
150                    } else {
151                        // regular value expression
152                        return new DynamicValueExpressionMetadata(attribute);
153                    }
154                }
155            }
156
157        }
158        return null;
159    }
160
161}