Package org.eclipse.persistence.sdo.helper.extension

Class OPStack

java.lang.Object
org.eclipse.persistence.sdo.helper.extension.OPStack
public class OPStack extends 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

  • Constructor Details

    • OPStack

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

  • Method Details

    • processExpression

      public List processExpression(String exp)
      Process an XPath Expression into postfix notation.
      Parameters:
      exp -
      Returns: