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Java in a Nutshell

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The java.beans Package
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23.15 java.beans.PropertyDescriptor (JDK 1.1)

A PropertyDescriptor object is a type of FeatureDescriptor that describes a single property of a Java bean. The BeanInfo class for a Java bean optionally creates and initializes PropertyDescriptor objects to describe the properties that the bean supports. Typically, only application builders and similar tools use the get and is methods to obtain this property description information.

You create a PropertyDescriptor by specifying the name of the property and the Class object for the bean. If you have not followed the standard "design patterns" for accessor method naming, you may also specify the accessor methods for the property. Once a PropertyDescriptor is created, the setBound() and setConstrained() methods allow you to specify whether the property is bound and/or constrained. setPropertyEditorClass() allows you to specify a specific property editor that should be used to edit the value of this property (this is useful, for example, when the property is an enumerated type with a specific list of supported values). The methods of the FeatureDescriptor superclass allow additional information about the property to be specified.

public class PropertyDescriptor extends FeatureDescriptor {
    // Public Constructors
            public PropertyDescriptor(String propertyName, Class beanClass) throws IntrospectionException;
            public PropertyDescriptor(String propertyName, Class beanClass, String getterName,
            public PropertyDescriptor'u'String setterName) throws IntrospectionException;
            public PropertyDescriptor(String propertyName, Method getter, Method setter) throws IntrospectionException;
    // Public Instance Methods
            public Class getPropertyEditorClass();
            public Class getPropertyType();
            public Method getReadMethod();
            public Method getWriteMethod();
            public boolean isBound();
            public boolean isConstrained();
            public void setBound(boolean bound);
            public void setConstrained(boolean constrained);
            public void setPropertyEditorClass(Class propertyEditorClass);
}

Hierarchy:

Object->FeatureDescriptor->PropertyDescriptor

Extended By:

IndexedPropertyDescriptor

Returned By:

BeanInfo.getPropertyDescriptors(), SimpleBeanInfo.getPropertyDescriptors()


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