org.apache.commons.jexl2.parser
Class JexlParser

java.lang.Object
  org.apache.commons.jexl2.parser.StringParser
      org.apache.commons.jexl2.parser.JexlParser

Direct Known Subclasses:

Parser

public class JexlParser
extends StringParser

The base class for parsing, manages the parameter/local variable frame.

Author:

henri

Field Summary

protected JexlEngine.Scope

frame The map of named registers aka script parameters.

Constructor Summary

JexlParser()

Method Summary

String	checkVariable(ASTIdentifier identifier, String image) Checks whether an identifier is a local variable or argument, ie stored in a register.
void	declareVariable(ASTVar identifier, String image) Declares a local variable.
JexlEngine.Scope	getFrame() Gets the frame used by this parser.
Token	getToken(int index)
void	Identifier()
void	Identifier(boolean top) Default implementation does nothing but is overriden by generated code.
void	setFrame(JexlEngine.Scope theFrame) Sets the frame to use bythis parser.

Methods inherited from class org.apache.commons.jexl2.parser.StringParser

buildString, escapeString, readString

Methods inherited from class java.lang.Object

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

Field Detail

frame

protected JexlEngine.Scope frame

The map of named registers aka script parameters. Each parameter is associated to a register and is materialized as an offset in the registers array used during evaluation.

Constructor Detail

JexlParser

public JexlParser()

Method Detail

setFrame

public void setFrame(JexlEngine.Scope theFrame)

Sets the frame to use bythis parser.

This is used to allow parameters to be declared before parsing.

Parameters:

theFrame - the register map

getFrame

public JexlEngine.Scope getFrame()

Gets the frame used by this parser.

Since local variables create new named registers, it is important to regain access after parsing to known which / how-many registers are needed.

Returns:

the named register map

checkVariable

public String checkVariable(ASTIdentifier identifier,
                            String image)

Checks whether an identifier is a local variable or argument, ie stored in a register.

Parameters:

identifier - the identifier

image - the identifier image

Returns:

the image

declareVariable

public void declareVariable(ASTVar identifier,
                            String image)

Declares a local variable.

This method creates an new entry in the named register map.

Parameters:

identifier - the identifier used to declare

image - the variable name

Identifier

public void Identifier(boolean top)
                throws ParseException

Default implementation does nothing but is overriden by generated code.

Parameters:

top - whether the identifier is beginning an l/r value

Throws:

ParseException - subclasses may throw this

Identifier

public final void Identifier()
                      throws ParseException

Throws:

ParseException

getToken

public Token getToken(int index)