org.apache.commons.beanutils.converters
Class BooleanConverter

java.lang.Object
  org.apache.commons.beanutils.converters.AbstractConverter
      org.apache.commons.beanutils.converters.BooleanConverter

All Implemented Interfaces:

Converter

public final class BooleanConverter
extends AbstractConverter

Converter implementaion that handles conversion to and from Boolean objects. Converter implementaion that handles conversion to and from java.lang.Boolean objects.

Can be configured to either return a default value or throw a ConversionException if a conversion error occurs.

By default any object whose string representation is one of the values {"yes", "y", "true", "on", "1"} is converted to Boolean.TRUE, and string representations {"no", "n", "false", "off", "0"} are converted to Boolean.FALSE. The recognised true/false strings can be changed by:

  String[] trueStrings = {"oui", "o", "1"};
  String[] falseStrings = {"non", "n", "0"};
  Converter bc = new BooleanConverter(trueStrings, falseStrings);
  ConvertUtils.register(bc, Boolean.class);
  ConvertUtils.register(bc, Boolean.TYPE);
 

In addition, it is recommended that the BooleanArrayConverter also be modified to recognise the same set of values:

   Converter bac = new BooleanArrayConverter(bc, BooleanArrayConverter.NO_DEFAULT);
   ConvertUtils.register(bac, bac.MODEL);
 

Case is ignored when converting values to true or false.

Since:

1.3

Version:

$Revision: 801644 $ $Date: 2009-08-06 14:38:56 +0100 (Thu, 06 Aug 2009) $

Author:

Craig R. McClanahan

Field Summary

static Object

NO_DEFAULT Deprecated. Use constructors without default value.

Constructor Summary

BooleanConverter()
Create a Converter that will throw a ConversionException if a conversion error occurs, ie the string value being converted is not one of the known true strings, nor one of the known false strings.

BooleanConverter(Object defaultValue)
Create a Converter that will return the specified default value if a conversion error occurs, ie the string value being converted is not one of the known true strings, nor one of the known false strings.

BooleanConverter(String[] trueStrings, String[] falseStrings)
Create a Converter that will throw a ConversionException if a conversion error occurs, ie the string value being converted is not one of the known true strings, nor one of the known false strings.

BooleanConverter(String[] trueStrings, String[] falseStrings, Object defaultValue)
Create a Converter that will return the specified default value if a conversion error occurs.

Method Summary

protected Object	convertToType(Class type, Object value) Convert the specified input object into an output object of the specified type.
protected Class	getDefaultType() Return the default type this Converter handles.

Methods inherited from class org.apache.commons.beanutils.converters.AbstractConverter

convert, convertArray, convertToString, getDefault, handleError, handleMissing, isUseDefault, setDefaultValue, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

NO_DEFAULT

public static final Object NO_DEFAULT

Deprecated. Use constructors without default value.

This is a special reference that can be passed as the "default object" to the constructor to indicate that no default is desired. Note that the value 'null' cannot be used for this purpose, as the caller may want a null to be returned as the default.

Constructor Detail

BooleanConverter

public BooleanConverter()

Create a Converter that will throw a ConversionException if a conversion error occurs, ie the string value being converted is not one of the known true strings, nor one of the known false strings.

BooleanConverter

public BooleanConverter(Object defaultValue)

Create a Converter that will return the specified default value if a conversion error occurs, ie the string value being converted is not one of the known true strings, nor one of the known false strings.

Parameters:

defaultValue - The default value to be returned if the value being converted is not recognised. This value may be null, in which case null will be returned on conversion failure. When non-null, it is expected that this value will be either Boolean.TRUE or Boolean.FALSE. The special value BooleanConverter.NO_DEFAULT can also be passed here, in which case this constructor acts like the no-argument one.

BooleanConverter

public BooleanConverter(String[] trueStrings,
                        String[] falseStrings)

Create a Converter that will throw a ConversionException if a conversion error occurs, ie the string value being converted is not one of the known true strings, nor one of the known false strings.

The provided string arrays are copied, so that changes to the elements of the array after this call is made do not affect this object.

Parameters:

trueStrings - is the set of strings which should convert to the value Boolean.TRUE. The value null must not be present. Case is ignored.

falseStrings - is the set of strings which should convert to the value Boolean.TRUE. The value null must not be present. Case is ignored.

Since:

1.8.0

BooleanConverter

public BooleanConverter(String[] trueStrings,
                        String[] falseStrings,
                        Object defaultValue)

Create a Converter that will return the specified default value if a conversion error occurs.

The provided string arrays are copied, so that changes to the elements of the array after this call is made do not affect this object.

Parameters:

trueStrings - is the set of strings which should convert to the value Boolean.TRUE. The value null must not be present. Case is ignored.

falseStrings - is the set of strings which should convert to the value Boolean.TRUE. The value null must not be present. Case is ignored.

defaultValue - The default value to be returned if the value being converted is not recognised. This value may be null, in which case null will be returned on conversion failure. When non-null, it is expected that this value will be either Boolean.TRUE or Boolean.FALSE. The special value BooleanConverter.NO_DEFAULT can also be passed here, in which case an exception will be thrown on conversion failure.

Since:

1.8.0

Method Detail

getDefaultType

protected Class getDefaultType()

Return the default type this Converter handles.

Specified by:

getDefaultType in class AbstractConverter

Returns:

The default type this Converter handles.

Since:

1.8.0

convertToType

protected Object convertToType(Class type,
                               Object value)
                        throws Throwable

Convert the specified input object into an output object of the specified type.

Specified by:

convertToType in class AbstractConverter

Parameters:

type - is the type to which this value should be converted. In the case of this BooleanConverter class, this value is ignored.

value - is the input value to be converted. The toString method shall be invoked on this object, and the result compared (ignoring case) against the known "true" and "false" string values.

Returns:

Boolean.TRUE if the value was a recognised "true" value, Boolean.FALSE if the value was a recognised "false" value, or the default value if the value was not recognised and the constructor was provided with a default value.

Throws:

Throwable - if an error occurs converting to the specified type

Since:

1.8.0