org.apache.commons.jexl2
Class ExpressionImpl

java.lang.Object
  org.apache.commons.jexl2.ExpressionImpl

All Implemented Interfaces:

Expression, Script

public class ExpressionImpl
extends Object
implements Expression, Script

Instances of ExpressionImpl are created by the JexlEngine, and this is the default implementation of the Expression and Script interface.

Since:

1.0

Field Summary

protected String	expression Original expression stripped from leading & trailing spaces.
protected JexlEngine	jexl The engine for this expression.
protected ASTJexlScript	script The resulting AST we can interpret.

Constructor Summary

protected

ExpressionImpl(JexlEngine engine, String expr, ASTJexlScript ref) Do not let this be generally instantiated with a 'new'.

Method Summary

Callable<Object>	callable(JexlContext context) Creates a Callable from this script.
Callable<Object>	callable(JexlContext context, Object... args) Creates a Callable from this script.
String	dump() Returns the JEXL expression by reconstructing it from the parsed tree.
Object	evaluate(JexlContext context) Evaluates the expression with the variables contained in the supplied JexlContext.
Object	execute(JexlContext context) Executes the script with the variables contained in the supplied JexlContext.
Object	execute(JexlContext context, Object... args) Executes the script with the variables contained in the supplied JexlContext and a set of arguments corresponding to the parameters used during parsing.
String	getExpression() Returns the JEXL expression this Expression was created with.
String[]	getLocalVariables() Gets this script local variables.
String[]	getParameters() Gets this script parameters.
String	getText() Returns the text of this Script.
Set<List<String>>	getVariables() Gets this script variables.
String	toString() Provide a string representation of this expression.

Methods inherited from class java.lang.Object

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

Field Detail

jexl

protected final JexlEngine jexl

The engine for this expression.

expression

protected final String expression

Original expression stripped from leading & trailing spaces.

script

protected final ASTJexlScript script

The resulting AST we can interpret.

Constructor Detail

ExpressionImpl

protected ExpressionImpl(JexlEngine engine,
                         String expr,
                         ASTJexlScript ref)

Do not let this be generally instantiated with a 'new'.

Parameters:

engine - the interpreter to evaluate the expression

expr - the expression.

ref - the parsed expression.

Method Detail

evaluate

public Object evaluate(JexlContext context)

Evaluates the expression with the variables contained in the supplied JexlContext.

Specified by:

evaluate in interface Expression

Parameters:

context - A JexlContext containing variables.

Returns:

The result of this evaluation

dump

public String dump()

Returns the JEXL expression by reconstructing it from the parsed tree.

Specified by:

dump in interface Expression

Returns:

the JEXL expression

getExpression

public String getExpression()

Returns the JEXL expression this Expression was created with.

Specified by:

getExpression in interface Expression

Returns:

The JEXL expression to be evaluated

toString

public String toString()

Provide a string representation of this expression.

Overrides:

toString in class Object

Returns:

the expression or blank if it's null.

getText

public String getText()

Returns the text of this Script.

Specified by:

getText in interface Script

Returns:

The script to be executed.

execute

public Object execute(JexlContext context)

Executes the script with the variables contained in the supplied JexlContext.

Specified by:

execute in interface Script

Parameters:

context - A JexlContext containing variables.

Returns:

The result of this script, usually the result of the last statement.

execute

public Object execute(JexlContext context,
                      Object... args)

Executes the script with the variables contained in the supplied JexlContext and a set of arguments corresponding to the parameters used during parsing.

Specified by:

execute in interface Script

Parameters:

context - A JexlContext containing variables.

args - the arguments

Returns:

The result of this script, usually the result of the last statement.

Since:

2.1

getParameters

public String[] getParameters()

Gets this script parameters.

Specified by:

getParameters in interface Script

Returns:

the parameters or null

Since:

2.1

getLocalVariables

public String[] getLocalVariables()

Gets this script local variables.

Specified by:

getLocalVariables in interface Script

Returns:

the local variables or null

Since:

2.1

getVariables

public Set<List<String>> getVariables()

Gets this script variables.

Note that since variables can be in an ant-ish form (ie foo.bar.quux), each variable is returned as a list of strings where each entry is a fragment of the variable ({"foo", "bar", "quux"} in the example.

Specified by:

getVariables in interface Script

Returns:

the variables or null

Since:

2.1

callable

public Callable<Object> callable(JexlContext context)

Creates a Callable from this script.

This allows to submit it to an executor pool and provides support for asynchronous calls.

The interpreter will handle interruption/cancellation gracefully if needed.

Specified by:

callable in interface Script

Parameters:

context - the context

Returns:

the callable

Since:

2.1

callable

public Callable<Object> callable(JexlContext context,
                                 Object... args)

Creates a Callable from this script.

This allows to submit it to an executor pool and provides support for asynchronous calls.

The interpreter will handle interruption/cancellation gracefully if needed.

Specified by:

callable in interface Script

Parameters:

context - the context

args - the script arguments

Returns:

the callable

Since:

2.1