001 /*
002 * Copyright (c) 2005 Stephen J. McConnell
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
013 * implied.
014 *
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019 package net.dpml.metro.tools;
020
021 import java.util.ArrayList;
022 import java.util.List;
023
024 import net.dpml.lang.Value;
025
026 import net.dpml.metro.data.ValueDirective;
027
028 import org.apache.tools.ant.BuildException;
029
030 /**
031 * Defintion of a context entry parameter directive.
032 *
033 * @author <a href="http://www.dpml.net">Digital Product Meta Library</a>
034 * @version 1.2.0
035 */
036 public class ValueDataType implements ValueBuilder
037 {
038 private String m_classname;
039 private String m_method;
040 private String m_value;
041 private List m_params = new ArrayList();
042
043 /**
044 * Set the context entry classname.
045 * @param classname the context entry classname
046 */
047 public void setClass( final String classname )
048 {
049 m_classname = classname;
050 }
051
052 /**
053 * Set the method name.
054 * @param method the name of a static method
055 */
056 public void setMethod( final String method )
057 {
058 m_method = method;
059 }
060
061 /**
062 * Return the context entry parameter classname.
063 * @return the classname
064 */
065 public String getClassname()
066 {
067 return m_classname;
068 }
069
070 /**
071 * Return the context entry parameter classname.
072 * @return the classname
073 */
074 String getMethodName()
075 {
076 return m_method;
077 }
078
079 /**
080 * Set the value of the context entry parameter.
081 * @param value the param value
082 */
083 public void setValue( final String value )
084 {
085 m_value = value;
086 }
087
088 /**
089 * Return the value of the context entry param.
090 * @return the value
091 */
092 public String getValue()
093 {
094 return m_value;
095 }
096
097 /**
098 * Create, assign and return a new nested entry constructor parameter.
099 * @return the new context entry param
100 */
101 public ValueDataType createValue()
102 {
103 final ValueDataType param = new ValueDataType();
104 m_params.add( param );
105 return param;
106 }
107
108 /**
109 * Return the set of nested param directives.
110 * @return the params
111 */
112 public ValueBuilder[] getValueBuilders()
113 {
114 return (ValueBuilder[]) m_params.toArray( new ValueBuilder[0] );
115 }
116
117 /**
118 * Build a value datastructure.
119 * @param classloader the working classloader
120 * @return the serializable value descriptor
121 */
122 public Value buildValue( ClassLoader classloader )
123 {
124 String classname = getClassname();
125 String method = getMethodName();
126 String value = getValue();
127 if( null != value )
128 {
129 return new ValueDirective( classname, method, value );
130 }
131 else
132 {
133 ValueBuilder[] params = getValueBuilders();
134 Value[] values = new Value[ params.length ];
135 for( int i=0; i<values.length; i++ )
136 {
137 ValueBuilder p = params[i];
138 values[i] = p.buildValue( classloader );
139 }
140 return new ValueDirective( classname, method, values );
141 }
142 }
143
144 /**
145 * Return the base classname.
146 * @param classloader the working classloader
147 * @return the target class
148 */
149 public Class getTargetClass( ClassLoader classloader )
150 {
151 String classname = getClassname();
152 return getBaseClass( classloader, classname );
153 }
154
155 private Class getBaseClass( ClassLoader classloader, String classname )
156 {
157 if( null == classname )
158 {
159 return String.class;
160 }
161 else
162 {
163 try
164 {
165 return classloader.loadClass( classname );
166 }
167 catch( ClassNotFoundException e )
168 {
169 final String error =
170 "The value type base class [" + classname + "] is unknown.";
171 throw new BuildException( error, e );
172 }
173 }
174 }
175 }