org.apache.commons.jexl.parser

Class SimpleNode

java.lang.Object

org.apache.commons.jexl.parser.SimpleNode

All Implemented Interfaces:

Node

Direct Known Subclasses:

ASTAddNode, ASTAndNode, ASTArrayAccess, ASTAssignment, ASTBitwiseAndNode, ASTBitwiseComplNode, ASTBitwiseOrNode, ASTBitwiseXorNode, ASTBlock, ASTDivNode, ASTEmptyFunction, ASTEQNode, ASTExpression, ASTExpressionExpression, ASTFalseNode, ASTFloatLiteral, ASTForeachStatement, ASTGENode, ASTGTNode, ASTIdentifier, ASTIfStatement, ASTIntegerLiteral, ASTJexlScript, ASTLENode, ASTLTNode, ASTMethod, ASTModNode, ASTMulNode, ASTNENode, ASTNotNode, ASTNullLiteral, ASTOrNode, ASTReference, ASTReferenceExpression, ASTSizeFunction, ASTSizeMethod, ASTStatementExpression, ASTStringLiteral, ASTSubtractNode, ASTTrueNode, ASTUnaryMinusNode, ASTWhileStatement

public class SimpleNode
extends java.lang.Object
implements Node

A Useful implementation of Node. Mostly autogenerated by javacc

Version:

$Id: SimpleNode.java 398328 2006-04-30 12:46:59Z dion $

Author:

Geir Magnusson Jr.

Field Summary

Fields

Modifier and Type	Field and Description
protected Node[]	children children of this node.
protected int	id id of the node.
protected Node	parent parent node.
protected Parser	parser parser that created the node.

Constructor Summary

Constructors

Constructor and Description
SimpleNode(int i) Create the node given an id.
SimpleNode(Parser p, int i) Create a node with the given parser and id.

Method Summary

Modifier and Type	Method and Description
java.lang.Object	childrenAccept(ParserVisitor visitor, java.lang.Object data) Visit all children.
void	dump(java.lang.String prefix) Dump the node and all children.
java.lang.Object	execute(java.lang.Object o, JexlContext ctx) Used to let a node calcuate it's value..
boolean	interpret(JexlContext pc) basic interpret - just invoke interpret on all children.
java.lang.Object	jjtAccept(ParserVisitor visitor, java.lang.Object data) Accept the visitor.
void	jjtAddChild(Node n, int i) This method tells the node to add its argument to the node's list of children.
void	jjtClose() End of the node.
Node	jjtGetChild(int i) This method returns a child node.
int	jjtGetNumChildren() Gets the number of children the node has.
Node	jjtGetParent() Gets the parent node.
void	jjtOpen() Start of the node.
void	jjtSetParent(Node n) This pair of methods are used to inform the node of its parent.
java.lang.Object	setValue(JexlContext context, java.lang.Object value) Sets the value for the node - again, only makes sense for some nodes but lazyness tempts me to put it here.
java.lang.String	toString() Gets a string representation of the node.
java.lang.String	toString(java.lang.String prefix) Used during dumping to output the node with a prefix.
java.lang.Object	value(JexlContext context) Gets the value of this node.

Methods inherited from class java.lang.Object

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

Field Detail

parent

protected Node parent

parent node.

children

protected Node[] children

children of this node.

id

protected int id

id of the node.

parser

protected Parser parser

parser that created the node.

Constructor Detail

SimpleNode

public SimpleNode(int i)

Create the node given an id.

Parameters:

i - node id.

SimpleNode

public SimpleNode(Parser p,
                  int i)

Create a node with the given parser and id.

Parameters:

p - a parser.

i - node id.

Method Detail

jjtOpen

public void jjtOpen()

Start of the node.

Specified by:

jjtOpen in interface Node

jjtClose

public void jjtClose()

End of the node.

Specified by:

jjtClose in interface Node

jjtSetParent

public void jjtSetParent(Node n)

This pair of methods are used to inform the node of its parent.

Specified by:

jjtSetParent in interface Node

Parameters:

n - the parent node.

jjtGetParent

public Node jjtGetParent()

Gets the parent node.

Specified by:

jjtGetParent in interface Node

Returns:

the parent to this node.

jjtAddChild

public void jjtAddChild(Node n,
                        int i)

This method tells the node to add its argument to the node's list of children.

Specified by:

jjtAddChild in interface Node

Parameters:

n - the child node to add

i - the index to add it at.

jjtGetChild

public Node jjtGetChild(int i)

This method returns a child node. The children are numbered from zero, left to right.

Specified by:

jjtGetChild in interface Node

Parameters:

i - the index of the child to get.

Returns:

the child at the given index.

jjtGetNumChildren

public int jjtGetNumChildren()

Gets the number of children the node has.

Specified by:

jjtGetNumChildren in interface Node

Returns:

the number of children the node has.

jjtAccept

public java.lang.Object jjtAccept(ParserVisitor visitor,
                                  java.lang.Object data)

Accept the visitor.

Specified by:

jjtAccept in interface Node

Parameters:

visitor - a ParserVisitor.

data - data to be passed along to the visitor.

Returns:

the value from visiting.

See Also:

ParserVisitor.visit(org.apache.commons.jexl.parser.SimpleNode, java.lang.Object)

childrenAccept

public java.lang.Object childrenAccept(ParserVisitor visitor,
                                       java.lang.Object data)

Visit all children.

Parameters:

visitor - a ParserVisitor.

data - data to be passed along to the visitor.

Returns:

the value from visiting.

See Also:

ParserVisitor.visit(org.apache.commons.jexl.parser.SimpleNode, java.lang.Object)

toString

public java.lang.String toString()

Gets a string representation of the node.

Overrides:

toString in class java.lang.Object

Returns:

the node name.

toString

public java.lang.String toString(java.lang.String prefix)

Used during dumping to output the node with a prefix.

Parameters:

prefix - text to prefix toString()

Returns:

text.

dump

public void dump(java.lang.String prefix)

Dump the node and all children.

Parameters:

prefix - text to prefix the node output.

interpret

public boolean interpret(JexlContext pc)
                  throws java.lang.Exception

basic interpret - just invoke interpret on all children.

Parameters:

pc - the context to interpret against.

Returns:

true if interpretation worked.

Throws:

java.lang.Exception - on any error.

value

public java.lang.Object value(JexlContext context)
                       throws java.lang.Exception

Gets the value of this node.

Parameters:

context - the context to retrieve values from.

Returns:

the value of the node.

Throws:

java.lang.Exception - when evaluating the operands fails.

setValue

public java.lang.Object setValue(JexlContext context,
                                 java.lang.Object value)
                          throws java.lang.Exception

Sets the value for the node - again, only makes sense for some nodes but lazyness tempts me to put it here. Keeps things simple.

Parameters:

context - the context to retrieve values from.

value - the value.

Returns:

the result.

Throws:

java.lang.Exception - when evaluating the operands fails.

execute

public java.lang.Object execute(java.lang.Object o,
                                JexlContext ctx)
                         throws java.lang.Exception

Used to let a node calcuate it's value..

Parameters:

o - the object to calculate with.

ctx - the context to retrieve values from.

Returns:

the result of the calculation.

Throws:

java.lang.Exception - when calculating the value fails.