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/*
* 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;
import java.util.List;
import org.apache.commons.beanutils.ConversionException;
/**
* Standard {@link org.apache.commons.beanutils.Converter} implementation that converts an incoming
* String into a primitive array of boolean. On a conversion failure, returns
* a specified default value or throws a {@link ConversionException} depending
* on how this instance is constructed.
*
* By default, the values to be converted are expected to be those
* recognised by a default instance of BooleanConverter. A customised
* BooleanConverter can be provided in order to recognise alternative values
* as true/false.
*
* @author Craig R. McClanahan
* @version $Revision: 690380 $ $Date: 2008-08-29 16:04:38 -0400 (Fri, 29 Aug 2008) $
* @since 1.4
* @deprecated Replaced by the new {@link ArrayConverter} implementation
*/
public final class BooleanArrayConverter extends AbstractArrayConverter {
// ----------------------------------------------------------- Constructors
/**
* Create a {@link org.apache.commons.beanutils.Converter} that will throw
* a {@link ConversionException} if a conversion error occurs.
*
* Conversion of strings to boolean values will be done via a default
* instance of class BooleanConverter.
*/
public BooleanArrayConverter() {
super();
this.booleanConverter = DEFAULT_CONVERTER;
}
/**
* Create a {@link org.apache.commons.beanutils.Converter} that will return
* the specified default value if a conversion error occurs.
*
* Conversion of strings to boolean values will be done via a default
* instance of class BooleanConverter.
*
* @param defaultValue The default value to be returned
*/
public BooleanArrayConverter(Object defaultValue) {
super(defaultValue);
this.booleanConverter = DEFAULT_CONVERTER;
}
/**
* Create a {@link org.apache.commons.beanutils.Converter} that will return
* the specified default value if a conversion error occurs.
*
* Conversion of strings to boolean values will be done via the
* specified converter.
*
* @param converter is the converter object that will be used to
* convert each input string-value into a boolean.
*
* @param defaultValue is the default value to be returned by method
* convert if conversion fails; null is a valid default value. See the
* documentation for method "convert" for more information.
* The value BooleanArrayConverter.NO_DEFAULT may be passed here to
* specify that an exception should be thrown on conversion failure.
*
*/
public BooleanArrayConverter(BooleanConverter converter, Object defaultValue) {
super(defaultValue);
this.booleanConverter = converter;
}
// ------------------------------------------------------- Static Variables
/**
* Type which this class converts its input to. This value can be
* used as a parameter to the ConvertUtils.register method.
* @since 1.8.0
*/
public static final Class MODEL = new boolean[0].getClass();
/**
* The converter that all instances of this class will use to
* do individual string->boolean conversions, unless overridden
* in the constructor.
*/
private static final BooleanConverter DEFAULT_CONVERTER
= new BooleanConverter();
// ---------------------------------------------------- Instance Variables
/**
* This object is used to perform the conversion of individual strings
* into Boolean/boolean values.
*/
protected final BooleanConverter booleanConverter;
// --------------------------------------------------------- Public Methods
/**
* Convert the specified input object into an output object of type
* array-of-boolean.
*
* If the input value is null, then the default value specified in the
* constructor is returned. If no such value was provided, then a
* ConversionException is thrown instead.
*
* If the input value is of type String[] then the returned array shall
* be of the same size as this array, with a true or false value in each
* array element depending on the result of applying method
* BooleanConverter.convert to each string.
*
* For all other types of value, the object's toString method is
* expected to return a string containing a comma-separated list of
* values, eg "true, false, true". See the documentation for
* {@link AbstractArrayConverter#parseElements} for more information on
* the exact formats supported.
*
* If the result of value.toString() cannot be split into separate
* words, then the default value is also returned (or an exception thrown).
*
*
* If any of the elements in the value array (or the elements resulting
* from splitting up value.toString) are not recognised by the
* BooleanConverter associated with this object, then what happens depends
* on whether that BooleanConverter has a default value or not: if it does,
* then that unrecognised element is converted into the BooleanConverter's
* default value. If the BooleanConverter does not have a default
* value, then the default value for this object is returned as the
* complete conversion result (not just for the element), or an
* exception is thrown if this object has no default value defined.
*
* @param type is the type to which this value should be converted. In the
* case of this BooleanArrayConverter class, this value is ignored.
*
* @param value is the input value to be converted.
*
* @return an object of type boolean[], or the default value if there was
* any sort of error during conversion and the constructor
* was provided with a default value.
*
* @exception ConversionException if conversion cannot be performed
* successfully and the constructor was not provided with a default
* value to return on conversion failure.
*
* @exception NullPointerException if value is an array, and any of the
* array elements are null.
*/
public Object convert(Class type, Object value) {
// Deal with a null value
if (value == null) {
if (useDefault) {
return (defaultValue);
} else {
throw new ConversionException("No value specified");
}
}
// Deal with the no-conversion-needed case
if (MODEL == value.getClass()) {
return (value);
}
// Deal with input value as a String array
//
// TODO: use if (value.getClass().isArray() instead...
// this requires casting to Object[], then using values[i].toString()
if (strings.getClass() == value.getClass()) {
try {
String[] values = (String[]) value;
boolean[] results = new boolean[values.length];
for (int i = 0; i < values.length; i++) {
String stringValue = values[i];
Object result = booleanConverter.convert(Boolean.class, stringValue);
results[i] = ((Boolean) result).booleanValue();
}
return (results);
} catch (Exception e) {
if (useDefault) {
return (defaultValue);
} else {
throw new ConversionException(value.toString(), e);
}
}
}
// We only get here if the input value is not of type String[].
// In this case, we assume value.toString() returns a comma-separated
// sequence of values; see method AbstractArrayConverter.parseElements
// for more information.
try {
List list = parseElements(value.toString());
boolean[] results = new boolean[list.size()];
for (int i = 0; i < results.length; i++) {
String stringValue = (String) list.get(i);
Object result = booleanConverter.convert(Boolean.class, stringValue);
results[i] = ((Boolean) result).booleanValue();
}
return (results);
} catch (Exception e) {
if (useDefault) {
return (defaultValue);
} else {
throw new ConversionException(value.toString(), e);
}
}
}
}