org.apache.turbine.modules.screens

Class RawScreen

java.lang.Object

org.apache.turbine.modules.screens.RawScreen

All Implemented Interfaces:

Assembler, Screen

Direct Known Subclasses:

JSONScreen, PlainJSONScreen

public abstract class RawScreen
extends Object
implements Screen

Base class for writing Screens that output binary data. This class is provided as a helper class for those who want to write Screens that output raw binary data. For example, it may be extended into a Screen that outputs a SVG file or a SWF (Flash Player format) movie. The only thing one has to do is to implement the two methods getContentType(PipelineData data) and doOutput(PipelineData data) (see below).

You might want to take a look at the ImageServer screen class contained in the TDK.

Version:

$Id: RawScreen.java 1854797 2019-03-04 20:41:39Z tv $

Author:

Regis Koenig, Peter Courcoux

Field Summary

Fields inherited from interface org.apache.turbine.modules.Screen

CACHE_SIZE_DEFAULT, CACHE_SIZE_KEY, NAME, PREFIX

Constructor Summary

Constructors

Constructor and Description
RawScreen()

Method Summary

Modifier and Type	Method and Description
String	doBuild(PipelineData pipelineData) Build the Screen.
protected abstract void	doOutput(PipelineData pipelineData) Actually output the dynamic content.
protected abstract String	getContentType(PipelineData pipelineData) Set the content type.
String	getLayout(PipelineData pipelineData) The layout must be set to null.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.turbine.modules.Screen

build, setLayout

Constructor Detail

RawScreen

public RawScreen()

Method Detail

doBuild

public final String doBuild(PipelineData pipelineData)
                     throws Exception

Build the Screen. This method actually makes a call to the doOutput() method in order to generate the Screen content.

Specified by:

doBuild in interface Screen

Parameters:

pipelineData - Turbine information.

Returns:

A ConcreteElement.

Throws:

Exception - a generic exception.

getContentType

protected abstract String getContentType(PipelineData pipelineData)

Set the content type. This method should be overridden to actually set the real content-type header of the output.

Parameters:

pipelineData - Turbine information.

Returns:

A String with the content type.

doOutput

protected abstract void doOutput(PipelineData pipelineData)
                          throws Exception

Actually output the dynamic content. The OutputStream can be accessed like this:

OutputStream out =
 data.getResponse().getOutputStream();

.

Parameters:

pipelineData - Turbine information.

Throws:

Exception - a generic exception.

getLayout

public final String getLayout(PipelineData pipelineData)

The layout must be set to null.

Specified by:

getLayout in interface Screen

Parameters:

pipelineData - Turbine information.

Returns:

A null String.