/*
* Copyright 2007 Kasper B. Graversen
*
* Licensed 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.supercsv.cellprocessor;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import org.supercsv.cellprocessor.ift.BoolCellProcessor;
import org.supercsv.cellprocessor.ift.StringCellProcessor;
import org.supercsv.exception.SuperCsvCellProcessorException;
import org.supercsv.util.CsvContext;
/**
* Converts a String to a Boolean.
* <p>
* The default values for true are: <tt>"true", "1", "y", "t"</tt>
* <p>
* The default values for false are: <tt>"false", "0", "n", "f"</tt>
* <p>
* The input is converted to lowercase before comparison against the true/false values (to handle all variations of case
* in the input), so if you supply your own true/false values then ensure they are lowercase.
*
* @author Kasper B. Graversen
* @author Dominique De Vito
* @author James Bassett
* @since 1.0
*/
public class ParseBool extends CellProcessorAdaptor implements StringCellProcessor {
private static final String[] DEFAULT_TRUE_VALUES = new String[] { "1", "true", "t", "y" };
private static final String[] DEFAULT_FALSE_VALUES = new String[] { "0", "false", "f", "n" };
private final Set<String> trueValues = new HashSet<String>();
private final Set<String> falseValues = new HashSet<String>();
/**
* Constructs a new <tt>ParseBool</tt> processor, which converts a String to a Boolean using the default values.
*/
public ParseBool() {
this(DEFAULT_TRUE_VALUES, DEFAULT_FALSE_VALUES);
}
/**
* Constructs a new <tt>ParseBool</tt> processor, which converts a String to a Boolean using the default values,
* then calls the next processor in the chain.
*
* @param next
* the next processor in the chain
* @throws NullPointerException
* if next is null
*/
public ParseBool(final BoolCellProcessor next) {
this(DEFAULT_TRUE_VALUES, DEFAULT_FALSE_VALUES, next);
}
/**
* Constructs a new <tt>ParseBool</tt> processor, which converts a String to a Boolean using the supplied true/false
* values.
*
* @param trueValue
* the String which represents true
* @param falseValue
* the String which represents false
* @throws NullPointerException
* if trueValue or falseValue is null
*/
public ParseBool(final String trueValue, final String falseValue) {
super();
checkPreconditions(trueValue, falseValue);
trueValues.add(trueValue);
falseValues.add(falseValue);
}
/**
* Constructs a new <tt>ParseBool</tt> processor, which converts a String to a Boolean using the supplied true/false
* values.
*
* @param trueValues
* the array of Strings which represent true
* @param falseValues
* the array of Strings which represent false
* @throws IllegalArgumentException
* if trueValues or falseValues is empty
* @throws NullPointerException
* if trueValues or falseValues is null
*/
public ParseBool(final String[] trueValues, final String[] falseValues) {
super();
checkPreconditions(trueValues, falseValues);
Collections.addAll(this.trueValues, trueValues);
Collections.addAll(this.falseValues, falseValues);
}
/**
* Constructs a new <tt>ParseBool</tt> processor, which converts a String to a Boolean using the supplied true/false
* values, then calls the next processor in the chain.
*
* @param trueValue
* the String which represents true
* @param falseValue
* the String which represents false
* @param next
* the next processor in the chain
* @throws NullPointerException
* if trueValue, falseValue or next is null
*/
public ParseBool(final String trueValue, final String falseValue, final BoolCellProcessor next) {
super(next);
checkPreconditions(trueValue, falseValue);
trueValues.add(trueValue);
falseValues.add(falseValue);
}
/**
* Constructs a new <tt>ParseBool</tt> processor, which converts a String to a Boolean using the supplied true/false
* values, then calls the next processor in the chain.
*
* @param trueValues
* the array of Strings which represent true
* @param falseValues
* the array of Strings which represent false
* @param next
* the next processor in the chain
* @throws IllegalArgumentException
* if trueValues or falseValues is empty
* @throws NullPointerException
* if trueValues, falseValues, or next is null
*/
public ParseBool(final String[] trueValues, final String[] falseValues, final BoolCellProcessor next) {
super(next);
checkPreconditions(trueValues, falseValues);
Collections.addAll(this.trueValues, trueValues);
Collections.addAll(this.falseValues, falseValues);
}
/**
* Checks the preconditions for constructing a new ParseBool processor.
*
* @param trueValue
* the String which represents true
* @param falseValue
* the String which represents false
* @throws NullPointerException
* if trueValue or falseValue is null
*/
private static void checkPreconditions(final String trueValue, final String falseValue) {
if( trueValue == null ) {
throw new NullPointerException("trueValue should not be null");
}
if( falseValue == null ) {
throw new NullPointerException("falseValue should not be null");
}
}
/**
* Checks the preconditions for constructing a new ParseBool processor.
*
* @param trueValues
* the array of Strings which represent true
* @param falseValues
* the array of Strings which represent false
* @throws IllegalArgumentException
* if trueValues or falseValues is empty
* @throws NullPointerException
* if trueValues or falseValues is null
*/
private static void checkPreconditions(final String[] trueValues, final String[] falseValues) {
if( trueValues == null ) {
throw new NullPointerException("trueValues should not be null");
} else if( trueValues.length == 0 ) {
throw new IllegalArgumentException("trueValues should not be empty");
}
if( falseValues == null ) {
throw new NullPointerException("falseValues should not be null");
} else if( falseValues.length == 0 ) {
throw new IllegalArgumentException("falseValues should not be empty");
}
}
/**
* {@inheritDoc}
*
* @throws SuperCsvCellProcessorException
* if value is null, not a String, or can't be parsed to a Boolean
*/
public Object execute(final Object value, final CsvContext context) {
validateInputNotNull(value, context);
if( !(value instanceof String) ) {
throw new SuperCsvCellProcessorException(String.class, value, context, this);
}
final String stringValue = ((String) value).toLowerCase();
final Boolean result;
if( trueValues.contains(stringValue) ) {
result = Boolean.TRUE;
} else if( falseValues.contains(stringValue) ) {
result = Boolean.FALSE;
} else {
throw new SuperCsvCellProcessorException(String.format("'%s' could not be parsed as a Boolean", value),
context, this);
}
return next.execute(result, context);
}
}
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