com.jgoodies.binding.value
Class AbstractConverter

java.lang.Object
  com.jgoodies.common.bean.AbstractBean
      com.jgoodies.binding.beans.Model
          com.jgoodies.binding.value.AbstractValueModel
              com.jgoodies.binding.value.AbstractWrappedValueModel
                  com.jgoodies.binding.value.AbstractConverter

All Implemented Interfaces:

ComponentModel, ComponentValueModel, ValueModel, com.jgoodies.common.bean.ObservableBean, com.jgoodies.common.bean.ObservableBean2, Serializable

Direct Known Subclasses:

ConverterFactory.BooleanNegator, ConverterFactory.BooleanToStringConverter, ConverterFactory.DoubleConverter, ConverterFactory.DoubleToIntegerConverter, ConverterFactory.FloatConverter, ConverterFactory.FloatToIntegerConverter, ConverterFactory.IntegerConverter, ConverterFactory.LongConverter, ConverterFactory.LongToIntegerConverter, ConverterFactory.StringConverter

public abstract class AbstractConverter
extends AbstractWrappedValueModel

An abstract class that minimizes the effort required to implement a type converter. A type converter is a ValueModel that converts the type of an object being held as a value in one ValueModel into another type.

More formally, a converting ValueModel VM1 converts the type T2 of an object being held as a value in one ValueModel VM2 into another type T1. When reading a value from VM1, instances of T2 are read from VM2 and are converted to T1. When storing a new value to VM1, the type converter will perform the inverse conversion and will convert an instance of T1 to T2.

The conversion must be performed when reading and writing values, as well as in the change notification. This class specifies abstract methods for the conversion from source to output, which is used to convert in #getValue and in the change notification. For the write conversion you must implement #setValue.

Most converters can set values converted by #convertFromSubject with #setValue. However, a converter may reject subject values to be converted and may reject values to be set - as any ValueModel.

Type converters should be used judiciously and only to bridge two ValueModels. Converters often use a generic but weak conversion, and so can be limited w.r.t. to localized formatting conventions.

When binding non-String values to a text UI component, consider using a JFormattedTextField. Formatted text fields provide a powerful means to convert strings to objects and handle many cases that arise around invalid input. Formatted text fields can be bound to ValueModels using the PropertyConnector class.

Version:

$Revision: 1.15 $

Author:

Karsten Lentzsch

See Also:

ValueModel, ConverterFactory, JFormattedTextField, PropertyConnector, Serialized Form

Field Summary

protected ValueModel

subject Holds the ValueModel that in turn holds the source value.

Fields inherited from class com.jgoodies.binding.value.AbstractValueModel

PROPERTYNAME_VALUE

Fields inherited from class com.jgoodies.common.bean.AbstractBean

changeSupport

Fields inherited from interface com.jgoodies.binding.value.ComponentValueModel

PROPERTYNAME_EDITABLE, PROPERTYNAME_ENABLED, PROPERTYNAME_VISIBLE

Fields inherited from interface com.jgoodies.binding.value.ComponentModel

PROPERTY_EDITABLE, PROPERTY_ENABLED, PROPERTY_VISIBLE

Constructor Summary

AbstractConverter(ValueModel subject)
Constructs an AbstractConverter on the given subject.

Method Summary

abstract Object	convertFromSubject(Object subjectValue) Converts a value from the subject to the type or format used by this converter.
protected PropertyChangeListener	createValueChangeHandler()
Object	getValue() Converts the subject's value and returns the converted value.

Methods inherited from class com.jgoodies.binding.value.AbstractWrappedValueModel

getWrappee, isEditable, isEnabled, isVisible, release, setEditable, setEnabled, setVisible

Methods inherited from class com.jgoodies.binding.value.AbstractValueModel

addValueChangeListener, booleanValue, doubleValue, fireValueChange, fireValueChange, fireValueChange, fireValueChange, fireValueChange, fireValueChange, fireValueChange, floatValue, getString, intValue, longValue, paramString, removeValueChangeListener, setValue, setValue, setValue, setValue, setValue, toString, valueString

Methods inherited from class com.jgoodies.binding.beans.Model

createPropertyChangeSupport, firePropertyChange

Methods inherited from class com.jgoodies.common.bean.AbstractBean

addPropertyChangeListener, addPropertyChangeListener, addVetoableChangeListener, addVetoableChangeListener, fireIndexedPropertyChange, fireIndexedPropertyChange, fireIndexedPropertyChange, fireMultiplePropertiesChanged, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, fireVetoableChange, fireVetoableChange, fireVetoableChange, fireVetoableChange, fireVetoableChange, fireVetoableChange, fireVetoableChange, getPropertyChangeListeners, getPropertyChangeListeners, getVetoableChangeListeners, getVetoableChangeListeners, removePropertyChangeListener, removePropertyChangeListener, removeVetoableChangeListener, removeVetoableChangeListener

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.jgoodies.binding.value.ValueModel

addValueChangeListener, removeValueChangeListener, setValue

Methods inherited from interface com.jgoodies.common.bean.ObservableBean2

addPropertyChangeListener, getPropertyChangeListeners, getPropertyChangeListeners, removePropertyChangeListener

Methods inherited from interface com.jgoodies.common.bean.ObservableBean

addPropertyChangeListener, removePropertyChangeListener

Field Detail

subject

protected final ValueModel subject

Holds the ValueModel that in turn holds the source value.

Constructor Detail

AbstractConverter

public AbstractConverter(ValueModel subject)

Constructs an AbstractConverter on the given subject.

Parameters:

subject - the ValueModel that holds the source value

Throws:

NullPointerException - if the subject is null

Method Detail

convertFromSubject

public abstract Object convertFromSubject(Object subjectValue)

Converts a value from the subject to the type or format used by this converter.

Parameters:

subjectValue - the subject's value

Returns:

the converted value in the type or format used by this converter

getValue

public Object getValue()

Converts the subject's value and returns the converted value.

Returns:

the converted subject value

createValueChangeHandler

protected PropertyChangeListener createValueChangeHandler()

Specified by:

createValueChangeHandler in class AbstractWrappedValueModel