/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.beanutils.converters;
/**
* {@link org.apache.commons.beanutils.Converter} implementaion that handles conversion
* to and from <b>java.lang.Class</b> objects.
* <p>
* The class will be loaded from the thread context class
* loader (if it exists); otherwise the class loader that loaded this class
* will be used.
* <p>
* Can be configured to either return a <i>default value</i> or throw a
* <code>ConversionException</code> if a conversion error occurs.
*
* @author Tomas Viberg
* @version $Revision: 690380 $ $Date: 2008-08-29 21:04:38 +0100 (Fri, 29 Aug 2008) $
* @since 1.4
*/
public final class ClassConverter extends AbstractConverter {
/**
* Construct a <b>java.lang.Class</b> <i>Converter</i> that throws
* a <code>ConversionException</code> if an error occurs.
*/
public ClassConverter() {
super();
}
/**
* Construct a <b>java.lang.Class</b> <i>Converter</i> that returns
* a default value if an error occurs.
*
* @param defaultValue The default value to be returned
* if the value to be converted is missing or an error
* occurs converting the value.
*/
public ClassConverter(Object defaultValue) {
super(defaultValue);
}
/**
* Return the default type this <code>Converter</code> handles.
*
* @return The default type this <code>Converter</code> handles.
* @since 1.8.0
*/
protected Class getDefaultType() {
return Class.class;
}
/**
* <p>Convert a java.lang.Class or object into a String.</p>
*
* @param value The input value to be converted
* @return the converted String value.
* @since 1.8.0
*/
protected String convertToString(Object value) {
return (value instanceof Class) ? ((Class)value).getName() : value.toString();
}
/**
* <p>Convert the input object into a java.lang.Class.</p>
*
* @param type Data type to which this value should be converted.
* @param value The input value to be converted.
* @return The converted value.
* @throws Throwable if an error occurs converting to the specified type
* @since 1.8.0
*/
protected Object convertToType(Class type, Object value) throws Throwable {
ClassLoader classLoader =
Thread.currentThread().getContextClassLoader();
if (classLoader != null) {
try {
return (classLoader.loadClass(value.toString()));
} catch (ClassNotFoundException ex) {
// Don't fail, carry on and try this class's class loader
// (see issue# BEANUTILS-263)
}
}
// Try this class's class loader
classLoader = ClassConverter.class.getClassLoader();
return (classLoader.loadClass(value.toString()));
}
}
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