org.apache.turbine.modules

Interface Screen

All Superinterfaces:

Assembler

All Known Implementing Classes:

BaseJspScreen, InvalidState, JSONScreen, JSONSecureScreen, JspErrorScreen, LegacyVelocityScreen, LegacyVelocitySecureScreen, PlainJSONScreen, PlainJSONSecureAnnotatedScreen, RawScreen, TemplateScreen, VelocityCachedScreen, VelocityDirectScreen, VelocityErrorScreen, VelocityScreen, VelocitySecureScreen

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface Screen
extends Assembler

This is the interface which defines the Screen modules.

Version:

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

Author:

Dave Bryson, Henning P. Schmiedehausen, Peter Courcoux

Field Summary

Fields

Modifier and Type	Field and Description
static int	CACHE_SIZE_DEFAULT The default size for the screen cache
static String	CACHE_SIZE_KEY Property for the size of the screen cache if caching is on
static String	NAME Represents Screen Objects
static String	PREFIX Prefix for screen related classes and templates

Method Summary

Modifier and Type	Method and Description
default String	build(PipelineData pipelineData) Subclasses can override this method to add additional functionality.
String	doBuild(PipelineData pipelineData) A subclass must implement this method to build itself.
default String	getLayout(PipelineData pipelineData) If the Layout has not been defined by the Screen then set the layout to be "DefaultLayout".
default void	setLayout(PipelineData pipelineData, String layout) Set the layout for a Screen.

Field Detail

PREFIX

static final String PREFIX

Prefix for screen related classes and templates

See Also:

Constant Field Values

CACHE_SIZE_KEY

static final String CACHE_SIZE_KEY

Property for the size of the screen cache if caching is on

See Also:

Constant Field Values

CACHE_SIZE_DEFAULT

static final int CACHE_SIZE_DEFAULT

The default size for the screen cache

See Also:

Constant Field Values

NAME

static final String NAME

Represents Screen Objects

See Also:

Constant Field Values

Method Detail

doBuild

String doBuild(PipelineData pipelineData)
        throws Exception

A subclass must implement this method to build itself. Subclasses override this method to store the screen in RunData or to write the screen to the output stream referenced in RunData.

Parameters:

pipelineData - Turbine information.

Returns:

the content of the screen

Throws:

Exception - a generic exception.

build

default String build(PipelineData pipelineData)
              throws Exception

Subclasses can override this method to add additional functionality.

Parameters:

pipelineData - Turbine information.

Returns:

the content of the screen

Throws:

Exception - a generic exception.

getLayout

default String getLayout(PipelineData pipelineData)

If the Layout has not been defined by the Screen then set the layout to be "DefaultLayout". The Screen object can also override this method to provide intelligent determination of the Layout to execute. You can also define that logic here as well if you want it to apply on a global scale. For example, if you wanted to allow someone to define Layout "preferences" where they could dynamically change the Layout for the entire site. The information for the request is passed in with the PipelineData object.

Parameters:

pipelineData - Turbine information.

Returns:

A String with the Layout.

setLayout

default void setLayout(PipelineData pipelineData,
                       String layout)

Set the layout for a Screen.

Parameters:

pipelineData - Turbine information.

layout - The layout name.