org.apache.commons.beanutils

Class DefaultBeanIntrospector

java.lang.Object

org.apache.commons.beanutils.DefaultBeanIntrospector

All Implemented Interfaces:

BeanIntrospector

public class DefaultBeanIntrospector
extends java.lang.Object
implements BeanIntrospector

The default BeanIntrospector implementation.

This class implements a default bean introspection algorithm based on the JDK classes in the java.beans package. It discovers properties conforming to the Java Beans specification.

This class is a singleton. The single instance can be obtained using the INSTANCE field. It does not define any state and thus can be shared by arbitrary clients. PropertyUtils per default uses this instance as its only BeanIntrospector object.

Since:

1.9

Version:

$Id: DefaultBeanIntrospector.java 1632171 2014-10-15 20:15:17Z ggregory $

Field Summary

Fields

Modifier and Type	Field and Description
private static java.lang.Class<?>[]	EMPTY_CLASS_PARAMETERS Constant for argument types of a method that expects no arguments.
static BeanIntrospector	INSTANCE The singleton instance of this class.
private static java.lang.Class<?>[]	LIST_CLASS_PARAMETER Constant for arguments types of a method that expects a list argument.
private org.apache.commons.logging.Log	log Log instance

Constructor Summary

Constructors

Modifier	Constructor and Description
private	DefaultBeanIntrospector() Private constructor so that no instances can be created.

Method Summary

Modifier and Type	Method and Description
private void	handleIndexedPropertyDescriptors(java.lang.Class<?> beanClass, java.beans.PropertyDescriptor[] descriptors) This method fixes an issue where IndexedPropertyDescriptor behaves differently in different versions of the JDK for 'indexed' properties which use java.util.List (rather than an array).
void	introspect(IntrospectionContext icontext) Performs introspection of a specific Java class.

Methods inherited from class java.lang.Object

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

Field Detail

INSTANCE

public static final BeanIntrospector INSTANCE

The singleton instance of this class.

EMPTY_CLASS_PARAMETERS

private static final java.lang.Class<?>[] EMPTY_CLASS_PARAMETERS

Constant for argument types of a method that expects no arguments.

LIST_CLASS_PARAMETER

private static final java.lang.Class<?>[] LIST_CLASS_PARAMETER

Constant for arguments types of a method that expects a list argument.

log

private final org.apache.commons.logging.Log log

Log instance

Constructor Detail

DefaultBeanIntrospector

private DefaultBeanIntrospector()

Private constructor so that no instances can be created.

Method Detail

introspect

public void introspect(IntrospectionContext icontext)

Performs introspection of a specific Java class. This implementation uses the java.beans.Introspector.getBeanInfo() method to obtain all property descriptors for the current class and adds them to the passed in introspection context.

Specified by:

introspect in interface BeanIntrospector

Parameters:

icontext - the introspection context

handleIndexedPropertyDescriptors

private void handleIndexedPropertyDescriptors(java.lang.Class<?> beanClass,
                                              java.beans.PropertyDescriptor[] descriptors)

This method fixes an issue where IndexedPropertyDescriptor behaves differently in different versions of the JDK for 'indexed' properties which use java.util.List (rather than an array). It implements a workaround for Bug 28358. If you have a Bean with the following getters/setters for an indexed property:

 public List getFoo()
 public Object getFoo(int index)
 public void setFoo(List foo)
 public void setFoo(int index, Object foo)
 

then the IndexedPropertyDescriptor's getReadMethod() and getWriteMethod() behave as follows:

• JDK 1.3.1_04: returns valid Method objects from these methods.
• JDK 1.4.2_05: returns null from these methods.

Parameters:

beanClass - the current class to be inspected

descriptors - the array with property descriptors