org.expressionj.util

Class ExpressionAnalyser

java.lang.Object

org.expressionj.util.ExpressionAnalyser

public class ExpressionAnalyser
extends java.lang.Object

This utility class allows to analyse an Expression.

Constructor Summary

Constructors

Constructor and Description
ExpressionAnalyser()

Method Summary

Modifier and Type	Method and Description
Constant	asConstant(Expression expr) Return the Expression as a Constant or null if this is not a Constant.
Variable	asVariable(Expression expr) Return the Expression as a Variable or null if this is not a Variable.
java.util.Map<java.lang.String,Variable>	getLocalVariables(Expression expr) Analyse an Expression to get the Map of local Variables which are defined in this expression.
java.util.Map<java.lang.String,Variable>	getVariables(Expression expr) Analyse an Expression to get the Map of Variables which are defined in this expression.
java.util.Map<java.lang.String,Variable>	getVariables(Expression expr, boolean includeLocals) Analyse an Expression to get the Map of Variables which are defined in this expression.
java.util.List<Variable>	getVariablesList(Expression expr) Analyse an Expression to get the list of Variables which are defined in this expression.
boolean	isConstant(Expression expr) Return true if an Expression is a constant.
boolean	isVariable(Expression expr) Return true if an Expression is a variable.

Methods inherited from class java.lang.Object

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

Constructor Detail

ExpressionAnalyser

public ExpressionAnalyser()

Method Detail

isConstant

public boolean isConstant(Expression expr)

Return true if an Expression is a constant.

Parameters:

expr - the expression

Returns:

true if the Expression is a constant

isVariable

public boolean isVariable(Expression expr)

Return true if an Expression is a variable.

Parameters:

expr - the expression

Returns:

true if the Expression is a variable

asConstant

public Constant asConstant(Expression expr)

Return the Expression as a Constant or null if this is not a Constant.

Parameters:

expr - the expression

Returns:

the Expression as a Constant or null if this is not a Constant

asVariable

public Variable asVariable(Expression expr)

Return the Expression as a Variable or null if this is not a Variable.

Parameters:

expr - the expression

Returns:

the Expression as a Variable or null if this is not a Variable

getVariablesList

public java.util.List<Variable> getVariablesList(Expression expr)

Analyse an Expression to get the list of Variables which are defined in this expression. The class will always return a not null list, which can be empty.

Parameters:

expr - the expression

Returns:

the list of Variables which are defined in this expression

getVariables

public java.util.Map<java.lang.String,Variable> getVariables(Expression expr)

Analyse an Expression to get the Map of Variables which are defined in this expression. The class will always return a not null Map, which can be empty.

Parameters:

expr - the expression

Returns:

the Map of Variables which are defined in this expression

getVariables

public java.util.Map<java.lang.String,Variable> getVariables(Expression expr,
                                                             boolean includeLocals)

Analyse an Expression to get the Map of Variables which are defined in this expression. The class will always return a not null Map, which can be empty.

Parameters:

expr - the expression

includeLocals - true if local variables shoudl be included

Returns:

the Map of Variables which are defined in this expression

getLocalVariables

public java.util.Map<java.lang.String,Variable> getLocalVariables(Expression expr)

Analyse an Expression to get the Map of local Variables which are defined in this expression. The class will always return a not null Map, which can be empty.

Parameters:

expr - the expression

Returns:

the Map of Variables which are defined in this expression