Package net.sf.basedb.util.jep

Class PositionFunction

java.lang.Object
net.sf.basedb.util.jep.PositionFunction
All Implemented Interfaces:
JepExpressionFunction, JepFunction, org.nfunk.jep.function.PostfixMathCommandI
public class PositionFunction extends Object implements JepExpressionFunction
A JEP function class that adds a pos function to a JEP expression parser. The function will look up position. For example: pos()

To be able to use this function it must be registered with the JEP parser. This function can only be used to convert a JEP expression to a Query API Expression. It doesn't support dynamic evalution.

Version:
2.0
Author:
Enell
See Also:
Last modified
$Date: 2015-04-20 11:08:18 +0200 (må, 20 apr 2015) $

  • Constructor Details

    • PositionFunction

      public PositionFunction()

  • Method Details

    • getFunctionName

      public String getFunctionName()
      Description copied from interface: JepFunction
      Get the name of this function. It is used when registering the function with a JEP parser.
      Specified by:
      getFunctionName in interface JepFunction
      Returns:
      The string "pos"
      See Also:

    • toExpression

      public Expression toExpression(Node node)
      Use the Dynamic.column(VirtualColumn) method to create an expression referencing a position.
      Specified by:
      toExpression in interface JepExpressionFunction
      Parameters:
      node - The node representing this function
      Returns:
      An Expression object

    • getNumberOfParameters

      public int getNumberOfParameters()
      Specified by:
      getNumberOfParameters in interface org.nfunk.jep.function.PostfixMathCommandI
      Returns:
      Always 0

    • setCurNumberOfParameters

      public void setCurNumberOfParameters(int n)
      Can't be changed.
      Specified by:
      setCurNumberOfParameters in interface org.nfunk.jep.function.PostfixMathCommandI

    • checkNumberOfParameters

      public boolean checkNumberOfParameters(int n)
      Specified by:
      checkNumberOfParameters in interface org.nfunk.jep.function.PostfixMathCommandI

    • run

      public void run(Stack stack) throws ParseException
      Specified by:
      run in interface org.nfunk.jep.function.PostfixMathCommandI
      Throws:
      ParseException