Skip navigation links

org.eclipse.persistence.sdo.helper.extension
Class OPStack

java.lang.Object
org.eclipse.persistence.sdo.helper.extension.OPStack

public class OPStack

extends java.lang.Object

Utility class used for processing an XPath Expression into postfix notation. For example, consider the following expression: quantity=5 and (specialOrder='false' or productName='Lawnmower') The operations performed to create a postfix expression are: 1) add "quantity" to the list 2) push "=" onto the stack 3) add "5" to the list 4) pop "=" off the stack, and add to the list 5) push "and" onto the stack 6) push "(" onto the stack 7) add "specialOrder" to the list 8) push "=" onto the stack 9) add "'false'" to the list 10) pop "=" off the stack, and add to the list 11) push "or" onto the stack 12) add "productName" to the list 13) push "=" onto the stack 14) add "'Lawnmower'" to the list 15) pop "=" off the stack, and add to the list 16) pop "or" off the stack, and add to the list 17) push ")" onto the stack 18) pop "(" ")" pair off the stack 19) pop "and" off the stack, and add to the list The resulting postfix expression is: quantity 5 = specialOrder 'false' = productName 'Lawnmower' = or and

Field Summary

private java.util.List	out Visibility reduced from [public] in 2.1.0.
private java.util.Stack	stack Visibility reduced from [public] in 2.1.0.
private int	state Visibility reduced from [public] in 2.1.0.
private java.util.ArrayList	tokens Visibility reduced from [public] in 2.1.0.

Constructor Summary

OPStack()
The default constructor initializes the stack and Token list.

Method Summary

private Token	getNextToken() Returns the next Token in the list.
private void	parseExpression(java.lang.String exp) Parse an XPath Expression into Token objects.
java.util.List	processExpression(java.lang.String exp) Process an XPath Expression into postfix notation.
private void	pushSpew(java.util.List outList, Token t) Removes lower priority tokens from the stack (adding them to the List that will be returned), then push the new token onto the stack.
private void	removeOCpair() Removes a '(' ')' pair from the stack.

Methods inherited from class java.lang.Object

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

Field Detail

state

private int state

Visibility reduced from [public] in 2.1.0. May 15 2007

stack

private java.util.Stack stack

Visibility reduced from [public] in 2.1.0. May 15 2007

tokens

private java.util.ArrayList tokens

Visibility reduced from [public] in 2.1.0. May 15 2007

out

private java.util.List out

Visibility reduced from [public] in 2.1.0. May 15 2007

Constructor Detail

OPStack

public OPStack()

The default constructor initializes the stack and Token list.

Method Detail

removeOCpair

private void removeOCpair()

Removes a '(' ')' pair from the stack.

pushSpew

private void pushSpew(java.util.List outList,
                      Token t)

Removes lower priority tokens from the stack (adding them to the List that will be returned), then push the new token onto the stack.

Parameters:

out -

t -

getNextToken

private Token getNextToken()

Returns the next Token in the list.

Returns:

parseExpression

private void parseExpression(java.lang.String exp)

Parse an XPath Expression into Token objects.

Parameters:

exp -

processExpression

public java.util.List processExpression(java.lang.String exp)

Process an XPath Expression into postfix notation.

Parameters:

exp -

Returns:

Skip navigation links