org.apache.commons.jelly.expression

Class CompositeExpression

java.lang.Object

org.apache.commons.jelly.expression.ExpressionSupport

org.apache.commons.jelly.expression.CompositeExpression

All Implemented Interfaces:

Expression

public class CompositeExpression
extends ExpressionSupport

CompositeExpression is a Composite expression made up of several Expression objects which are concatenated into a single String.

Version:

$Revision: 155420 $

Author:

James Strachan

Field Summary

Fields inherited from class org.apache.commons.jelly.expression.ExpressionSupport

EMPTY_ITERATOR

Fields inherited from interface org.apache.commons.jelly.expression.Expression

NULL

Constructor Summary

Constructors

Constructor and Description
CompositeExpression()
CompositeExpression(List expressions)

Method Summary

Methods

Modifier and Type	Method and Description
void	addExpression(Expression expression) Adds a new expression to the end of the expression list
void	addTextExpression(String text) A helper method to add a new constant text expression
Object	evaluate(JellyContext context) Evaluates the expression with the given context and returns the result
Iterator	evaluateAsIterator(JellyContext context) Evaluates the expression with the given context coercing the result to be an Iterator.
String	evaluateAsString(JellyContext context) Evaluates the expression with the given context coercing the result to be a String.
List	getExpressions()
String	getExpressionText()
static Expression	parse(String text, ExpressionFactory factory) Parses the given String to be either a ConstantExpression, an Expression denoted as "${foo}" or some String with embedded expressions such as "abc${something}def${else}xyz" which results in a CompositeExpression being returned.
void	setExpressions(List expressions) Sets the Expression objects that make up this composite expression
String	toString()

Methods inherited from class org.apache.commons.jelly.expression.ExpressionSupport

evaluateAsBoolean, evaluateRecurse

Methods inherited from class java.lang.Object

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

Constructor Detail

CompositeExpression

public CompositeExpression()

CompositeExpression

public CompositeExpression(List expressions)

Method Detail

toString

public String toString()

Overrides:

toString in class Object

parse

public static Expression parse(String text,
               ExpressionFactory factory)
                        throws JellyException

Parses the given String to be either a ConstantExpression, an Expression denoted as "${foo}" or some String with embedded expressions such as "abc${something}def${else}xyz" which results in a CompositeExpression being returned.

Parameters:

text - is the String to parse into expressions

factory - is the Factory of Expression objects used to create expressions for the contents of the String "foo" inside expressions such as "${foo}"

Returns:

the Expression for the given String.

Throws:

JellyException - if the text is invalid (such as missing '}' character).

JellyException - if there was some problem creating the underlying Expression object from the ExpressionFactory

getExpressions

public List getExpressions()

Returns:

the Expression objects that make up this composite expression

setExpressions

public void setExpressions(List expressions)

Sets the Expression objects that make up this composite expression

addExpression

public void addExpression(Expression expression)

Adds a new expression to the end of the expression list

addTextExpression

public void addTextExpression(String text)

A helper method to add a new constant text expression

getExpressionText

public String getExpressionText()

Returns:

the textual representation of this expression

evaluate

public Object evaluate(JellyContext context)

Description copied from interface: Expression

Evaluates the expression with the given context and returns the result

evaluateAsString

public String evaluateAsString(JellyContext context)

Description copied from interface: Expression

Evaluates the expression with the given context coercing the result to be a String.

Specified by:

evaluateAsString in interface Expression

Overrides:

evaluateAsString in class ExpressionSupport

evaluateAsIterator

public Iterator evaluateAsIterator(JellyContext context)

Description copied from interface: Expression

Evaluates the expression with the given context coercing the result to be an Iterator.

Specified by:

evaluateAsIterator in interface Expression

Overrides:

evaluateAsIterator in class ExpressionSupport