/*
* 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;
Converter
implementation that converts an incoming object into a java.lang.String
object.
Note that ConvertUtils really is designed to do string->object conversions,
and offers very little support for object->string conversions. The
ConvertUtils/ConvertUtilsBean methods only select a converter to apply
based upon the target type being converted to, and generally assume that
the input is a string (by calling its toString method if needed).
This class is therefore just a dummy converter that converts its input
into a string by calling the input object's toString method and returning
that value.
It is possible to replace this converter with something that has a big
if/else statement that selects behaviour based on the real type of the
object being converted (or possibly has a map of converters, and looks
them up based on the class of the input object). However this is not part
of the existing ConvertUtils framework.
Version: $Id$ Since: 1.3
/**
* {@link org.apache.commons.beanutils.Converter}
* implementation that converts an incoming
* object into a <code>java.lang.String</code> object.
* <p>
* Note that ConvertUtils really is designed to do string->object conversions,
* and offers very little support for object->string conversions. The
* ConvertUtils/ConvertUtilsBean methods only select a converter to apply
* based upon the target type being converted to, and generally assume that
* the input is a string (by calling its toString method if needed).
* <p>
* This class is therefore just a dummy converter that converts its input
* into a string by calling the input object's toString method and returning
* that value.
* <p>
* It is possible to replace this converter with something that has a big
* if/else statement that selects behaviour based on the real type of the
* object being converted (or possibly has a map of converters, and looks
* them up based on the class of the input object). However this is not part
* of the existing ConvertUtils framework.
*
*
* @version $Id$
* @since 1.3
*/
public final class StringConverter extends AbstractConverter {
Construct a java.lang.String Converter that throws
a ConversionException
if an error occurs.
/**
* Construct a <b>java.lang.String</b> <i>Converter</i> that throws
* a <code>ConversionException</code> if an error occurs.
*/
public StringConverter() {
super();
}
Construct a java.lang.String Converter that returns
a default value if an error occurs.
Params: - defaultValue – The default value to be returned
if the value to be converted is missing or an error
occurs converting the value.
/**
* Construct a <b>java.lang.String</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 StringConverter(final Object defaultValue) {
super(defaultValue);
}
Return the default type this Converter
handles.
Returns: The default type this Converter
handles. Since: 1.8.0
/**
* Return the default type this <code>Converter</code> handles.
*
* @return The default type this <code>Converter</code> handles.
* @since 1.8.0
*/
@Override
protected Class<?> getDefaultType() {
return String.class;
}
Convert the specified input object into an output object of the
specified type.
Params: - type – Data type to which this value should be converted.
- value – The input value to be converted.
Type parameters: - <T> – Target type of the conversion.
Throws: - Throwable – if an error occurs converting to the specified type
Returns: The converted value. Since: 1.8.0
/**
* Convert the specified input object into an output object of the
* specified type.
*
* @param <T> Target type of the conversion.
* @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
*/
@Override
protected <T> T convertToType(final Class<T> type, final Object value) throws Throwable {
// We have to support Object, too, because this class is sometimes
// used for a standard to Object conversion
if (String.class.equals(type) || Object.class.equals(type)) {
return type.cast(value.toString());
}
throw conversionException(type, value);
}
}