org.apache.commons.beanutils

Class FluentPropertyBeanIntrospector

java.lang.Object

org.apache.commons.beanutils.FluentPropertyBeanIntrospector

All Implemented Interfaces:

BeanIntrospector

public class FluentPropertyBeanIntrospector
extends Object
implements BeanIntrospector

An implementation of the BeanIntrospector interface which can detect write methods for properties used in fluent API scenario.

A fluent API allows setting multiple properties using a single statement by supporting so-called method chaining: Methods for setting a property value do not return void, but an object which can be called for setting another property. An example of such a fluent API could look as follows:

 public class FooBuilder {
     public FooBuilder setFooProperty1(String value) {
        ...
        return this;
    }

     public FooBuilder setFooProperty2(int value) {
        ...
        return this;
    }
 }
 

Per default, PropertyUtils does not detect methods like this because, having a non-void return type, they violate the Java Beans specification.

This class is more tolerant with regards to the return type of a set method. It basically iterates over all methods of a class and filters them for a configurable prefix (the default prefix is set). It then generates corresponding PropertyDescriptor objects for the methods found which use these methods as write methods.

An instance of this class is intended to collaborate with a DefaultBeanIntrospector object. So best results are achieved by adding this instance as custom BeanIntrospector after the DefaultBeanIntrospector object. Then default introspection finds read-only properties because it does not detect the write methods with a non-void return type. FluentPropertyBeanIntrospector completes the descriptors for these properties by setting the correct write method.

Since:

1.9

Version:

$Id$

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEFAULT_WRITE_METHOD_PREFIX The default prefix for write methods.

Constructor Summary

Constructors

Constructor and Description
FluentPropertyBeanIntrospector() Creates a new instance of FluentPropertyBeanIntrospector and sets the default prefix for write methods.
FluentPropertyBeanIntrospector(String writePrefix) Creates a new instance of FluentPropertyBeanIntrospector and initializes it with the prefix for write methods used by the classes to be inspected.

Method Summary

Modifier and Type	Method and Description
String	getWriteMethodPrefix() Returns the prefix for write methods this instance scans for.
void	introspect(IntrospectionContext icontext) Performs introspection.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_WRITE_METHOD_PREFIX

public static final String DEFAULT_WRITE_METHOD_PREFIX

The default prefix for write methods.

See Also:

Constant Field Values

Constructor Detail

FluentPropertyBeanIntrospector

public FluentPropertyBeanIntrospector(String writePrefix)

Creates a new instance of FluentPropertyBeanIntrospector and initializes it with the prefix for write methods used by the classes to be inspected.

Parameters:

writePrefix - the prefix for write methods (must not be null)

Throws:

IllegalArgumentException - if the prefix is null

FluentPropertyBeanIntrospector

public FluentPropertyBeanIntrospector()

Creates a new instance of FluentPropertyBeanIntrospector and sets the default prefix for write methods.

Method Detail

getWriteMethodPrefix

public String getWriteMethodPrefix()

Returns the prefix for write methods this instance scans for.

Returns:

the prefix for write methods

introspect

public void introspect(IntrospectionContext icontext)
                throws IntrospectionException

Performs introspection. This method scans the current class's methods for property write methods which have not been discovered by default introspection.

Specified by:

introspect in interface BeanIntrospector

Parameters:

icontext - the introspection context

Throws:

IntrospectionException - if an error occurs