org.apache.commons.workflow.base
Class BaseDescriptor

java.lang.Object
  org.apache.commons.workflow.base.BaseDescriptor

All Implemented Interfaces:

Descriptor

public class BaseDescriptor
extends Object
implements Descriptor

Basic implementation of the Descriptor interface.

Version:

$Revision: 155475 $ $Date: 2005-02-26 13:31:11 +0000 (Sat, 26 Feb 2005) $

Author:

Craig R. McClanahan

Field Summary

protected String	name The name of the Java object (in some scope).
protected String	scope The scope of the Java object.
protected Class	type The optional Java class expected by this Descriptor.
protected String	xpath The XPath expression used to access the Java object.

Constructor Summary

BaseDescriptor()
Create an instance with default values.

BaseDescriptor(String xpath)
Create an instance with the specified values.

BaseDescriptor(String xpath, Class type)
Create an instance with the specified values.

BaseDescriptor(String name, String scope)
Create an instance with the specified values.

BaseDescriptor(String name, String scope, Class type)
Create an instance with the specified values.

BaseDescriptor(String name, String scope, String xpath, Class type)
Create an instance with the specified values.

Method Summary

Object	get(Context context) Return the value specified by this Descriptor from the specified Context.
String	getName() Return the name of the Java object (in some scope) referenced by this Descriptor.
String	getScope() Return the scope of the Java object referenced by this Descriptor.
Class	getType() Return the optional Java class expected by this Descriptor.
String	getXpath() Return the XPath expression used to access the Java object referenced by this Descriptor.
boolean	positive(Context context) Call get() to retrieve the value specified by this Descriptor, and then return true if this value represents a positive result; otherwise return false.
void	put(Context context, Object value) Store the value into the destination specified by this Descriptor in the specified Context, replacing any existing value.
void	remove(Context context) Remove any existing value associated with this Descriptor from the specified Context.
void	setName(String name) Set the name of the Java object (in some scope) referenced by this Descriptor.
void	setScope(String scope) Set the scope of the Java object referenced by this Descriptor.
void	setType(Class type) Set the optional Java class expected by this Descriptor.
void	setXpath(String xpath) Set the XPath expression used to access the Java object referenced by this Descriptor.
String	toString() Render a printable version of this object.

Methods inherited from class java.lang.Object

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

Field Detail

name

protected String name

The name of the Java object (in some scope).

scope

protected String scope

The scope of the Java object.

type

protected Class type

The optional Java class expected by this Descriptor.

xpath

protected String xpath

The XPath expression used to access the Java object.

Constructor Detail

BaseDescriptor

public BaseDescriptor()

Create an instance with default values.

BaseDescriptor

public BaseDescriptor(String xpath)

Create an instance with the specified values.

Parameters:

xpath - The XPath reference expression

BaseDescriptor

public BaseDescriptor(String xpath,
                      Class type)

Create an instance with the specified values.

Parameters:

xpath - The XPath reference expression

type - The expected class of this object

BaseDescriptor

public BaseDescriptor(String name,
                      String scope)

Create an instance with the specified values.

Parameters:

name - The object name

scope - The object scope

BaseDescriptor

public BaseDescriptor(String name,
                      String scope,
                      Class type)

Create an instance with the specified values.

Parameters:

name - The object name

scope - The object scope

type - The expected class of this object

BaseDescriptor

public BaseDescriptor(String name,
                      String scope,
                      String xpath,
                      Class type)

Create an instance with the specified values.

Parameters:

name - The object name

scope - The object scope

xpath - The XPath reference expression

type - The expected class

Method Detail

getName

public String getName()

Return the name of the Java object (in some scope) referenced by this Descriptor.

Specified by:

getName in interface Descriptor

setName

public void setName(String name)

Set the name of the Java object (in some scope) referenced by this Descriptor.

Specified by:

setName in interface Descriptor

Parameters:

name - The new object name

getScope

public String getScope()

Return the scope of the Java object referenced by this Descriptor.

Specified by:

getScope in interface Descriptor

setScope

public void setScope(String scope)

Set the scope of the Java object referenced by this Descriptor.

Specified by:

setScope in interface Descriptor

Parameters:

scope - The new scope name

getType

public Class getType()

Return the optional Java class expected by this Descriptor.

Specified by:

getType in interface Descriptor

setType

public void setType(Class type)

Set the optional Java class expected by this Descriptor.

Specified by:

setType in interface Descriptor

Parameters:

type - The new expected type

getXpath

public String getXpath()

Return the XPath expression used to access the Java object referenced by this Descriptor.

Specified by:

getXpath in interface Descriptor

setXpath

public void setXpath(String xpath)

Set the XPath expression used to access the Java object referenced by this Descriptor.

Specified by:

setXpath in interface Descriptor

Parameters:

xpath - The new XPath expression

get

public Object get(Context context)

Return the value specified by this Descriptor from the specified Context. If there is no such value, return null.

Specified by:

get in interface Descriptor

Parameters:

context - Context from which to retrieve this value

positive

public boolean positive(Context context)

Call get() to retrieve the value specified by this Descriptor, and then return true if this value represents a positive result; otherwise return false. A positive result depends on the data type of the retrieved value:

• Value returned is a String of length greater than 0.
• Value is a Boolean "true".
• Value is a numeric primitive (byte, char, float, double, int, long, short), or an Object wrapper for one of these types, and the corresponding value is non-zero.
• Value returned is a non-null Object.

Specified by:

positive in interface Descriptor

Parameters:

context - Context from which to retrieve this value

put

public void put(Context context,
                Object value)

Store the value into the destination specified by this Descriptor in the specified Context, replacing any existing value.

Specified by:

put in interface Descriptor

Parameters:

context - Context into which to store this value

value - Object value to be stored

remove

public void remove(Context context)

Remove any existing value associated with this Descriptor from the specified Context.

Specified by:

remove in interface Descriptor

Parameters:

context - Context from which to remove this value.

toString

public String toString()

Render a printable version of this object.

Overrides:

toString in class Object