org.apache.log4j.config

Class PropertySetter

java.lang.Object

org.apache.log4j.config.PropertySetter

public class PropertySetter
extends Object

General purpose Object property setter. Clients repeatedly invokes setProperty(name,value) in order to invoke setters on the Object specified in the constructor. This class relies on the JavaBeans Introspector to analyze the given Object Class using reflection.

Usage:

 PropertySetter ps = new PropertySetter(anObject);
 ps.set("name", "Joe");
 ps.set("age", "32");
 ps.set("isMale", "true");
 

will cause the invocations anObject.setName("Joe"), anObject.setAge(32), and setMale(true) if such methods exist with those signatures. Otherwise an IntrospectionException are thrown.

Field Summary

Fields

Modifier and Type	Field and Description
protected Object	obj
protected PropertyDescriptor[]	props

Constructor Summary

Constructors

Constructor and Description
PropertySetter(Object obj) Create a new PropertySetter for the specified Object.

Method Summary

Modifier and Type	Method and Description
void	activate()
protected Object	convertArg(String val, Class<?> type) Convert val a String parameter to an object of a given type.
protected PropertyDescriptor	getPropertyDescriptor(String name)
protected void	introspect() Uses JavaBeans Introspector to computer setters of object to be configured.
static void	setProperties(Object obj, Properties properties, String prefix) Set the properties of an object passed as a parameter in one go.
void	setProperties(Properties properties, String prefix) Set the properites for the object that match the prefix passed as parameter.
void	setProperty(PropertyDescriptor prop, String name, String value) Set the named property given a PropertyDescriptor.
void	setProperty(String name, String value) Set a property on this PropertySetter's Object.

Methods inherited from class java.lang.Object

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

Field Detail

obj

protected Object obj

props

protected PropertyDescriptor[] props

Constructor Detail

PropertySetter

public PropertySetter(Object obj)

Create a new PropertySetter for the specified Object. This is done in prepartion for invoking setProperty(java.lang.String, java.lang.String) one or more times.

Parameters:

obj - the object for which to set properties

Method Detail

setProperties

public static void setProperties(Object obj,
                                 Properties properties,
                                 String prefix)

Set the properties of an object passed as a parameter in one go. The properties are parsed relative to a prefix.

Parameters:

obj - The object to configure.

properties - A java.util.Properties containing keys and values.

prefix - Only keys having the specified prefix will be set.

introspect

protected void introspect()

Uses JavaBeans Introspector to computer setters of object to be configured.

setProperties

public void setProperties(Properties properties,
                          String prefix)

Set the properites for the object that match the prefix passed as parameter.

Parameters:

properties - The properties.

prefix - The prefix of the properties to use.

setProperty

public void setProperty(String name,
                        String value)

Set a property on this PropertySetter's Object. If successful, this method will invoke a setter method on the underlying Object. The setter is the one for the specified property name and the value is determined partly from the setter argument type and partly from the value specified in the call to this method.

If the setter expects a String no conversion is necessary. If it expects an int, then an attempt is made to convert 'value' to an int using new Integer(value). If the setter expects a boolean, the conversion is by new Boolean(value).

Parameters:

name - name of the property

value - String value of the property

setProperty

public void setProperty(PropertyDescriptor prop,
                        String name,
                        String value)
                 throws PropertySetterException

Set the named property given a PropertyDescriptor.

Parameters:

prop - A PropertyDescriptor describing the characteristics of the property to set.

name - The named of the property to set.

value - The value of the property.

Throws:

PropertySetterException - if no setter is available.

convertArg

protected Object convertArg(String val,
                            Class<?> type)

Convert val a String parameter to an object of a given type.

Parameters:

val - The value to convert.

type - The type of the value to convert to.

Returns:

The result of the conversion.

getPropertyDescriptor

protected PropertyDescriptor getPropertyDescriptor(String name)

activate

public void activate()