org.apache.turbine.modules
Class ScreenLoader

java.lang.Object
  java.util.Dictionary
      java.util.Hashtable
          org.apache.turbine.modules.GenericLoader
              org.apache.turbine.modules.ScreenLoader

All Implemented Interfaces:

java.lang.Cloneable, Loader, java.util.Map, java.io.Serializable

public class ScreenLoader

extends GenericLoader

implements Loader

The purpose of this class is to allow one to load and execute Screen modules.

Version:

$Id: ScreenLoader.java 534527 2007-05-02 16:10:59Z tv $

Author:

Dave Bryson, Henning P. Schmiedehausen

See Also:

Serialized Form

Method Summary

org.apache.ecs.ConcreteElement	eval(RunData data, java.lang.String name) Attempts to load and execute the external Screen.
void	exec(RunData data, java.lang.String name) Attempts to load and execute the Screen.
Assembler	getAssembler(java.lang.String name) Pulls out an instance of the object by name.
static ScreenLoader	getInstance() The method through which this class is accessed.
Screen	getInstance(java.lang.String name) Pulls out an instance of the Screen by name.

Methods inherited from class org.apache.turbine.modules.GenericLoader

cache, getBasePackage, reload, setReload

Methods inherited from class java.util.Hashtable

clear, clone, contains, containsKey, containsValue, elements, entrySet, equals, get, hashCode, isEmpty, keys, keySet, put, putAll, rehash, remove, size, toString, values

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

eval

public org.apache.ecs.ConcreteElement eval(RunData data,
                                           java.lang.String name)
                                    throws java.lang.Exception

Attempts to load and execute the external Screen. This is used when you want to execute a Screen which returns its output via a MultiPartElement instead of out the data.getPage() value. This allows you to easily chain the execution of Screen modules together.

Parameters:

data - Turbine information.

name - Name of object that will execute the screen.

Throws:

java.lang.Exception - a generic exception.

exec

public void exec(RunData data,
                 java.lang.String name)
          throws java.lang.Exception

Attempts to load and execute the Screen. This is used when you want to execute a Screen which returns its output via the data.getPage() object.

Specified by:

exec in class GenericLoader

Parameters:

data - Turbine information.

name - Name of object that will execute the screen.

Throws:

java.lang.Exception - a generic exception.

getAssembler

public Assembler getAssembler(java.lang.String name)
                       throws java.lang.Exception

Pulls out an instance of the object by name. Name is just the single name of the object. This is equal to getInstance but returns an Assembler object and is needed to fulfil the Loader interface.

Specified by:

getAssembler in interface Loader

Parameters:

name - Name of object instance.

Returns:

A Screen with the specified name, or null.

Throws:

java.lang.Exception - a generic exception.

getInstance

public Screen getInstance(java.lang.String name)
                   throws java.lang.Exception

Pulls out an instance of the Screen by name. Name is just the single name of the Screen.

Parameters:

name - Name of requested Screen.

Returns:

A Screen with the specified name, or null.

Throws:

java.lang.Exception - a generic exception.

getInstance

public static ScreenLoader getInstance()

The method through which this class is accessed.

Returns:

The single instance of this class.