Package net.sf.basedb.util.jep

Interface JepExpressionFunction

All Superinterfaces:
JepFunction, org.nfunk.jep.function.PostfixMathCommandI
All Known Implementing Classes:
ChannelFunction, ExtraValueFunction, Log2Function, MeanFunction, PositionFunction, RawChannelFunction, RawFunction, ReporterFunction, ScoreFunction
public interface JepExpressionFunction extends JepFunction
This interface should be implemented by JEP functions that can also be converted into an Expression that can be used in queries.
Version:
2.0
Author:
Nicklas
See Also:
Last modified
$Date: 2009-04-06 14:52:39 +0200 (må, 06 apr 2009) $

  • Method Summary

    Modifier and Type
    Method
    Description
    Expression
    toExpression(Node node)
    Convert this function to an Expression that can be used in a query.

    Methods inherited from interface net.sf.basedb.util.jep.JepFunction

    getFunctionName

    Methods inherited from interface org.nfunk.jep.function.PostfixMathCommandI

    checkNumberOfParameters, getNumberOfParameters, run, setCurNumberOfParameters

  • Method Details

    • toExpression

      Expression toExpression(Node node)
      Convert this function to an Expression that can be used in a query. The implementation must check that the node contains the correct number of children (ie. arguments to the function) and convert the arguments to whatever is suitable for the expression. Example from the Log2Function 
      int numChildren = node.jjtGetNumChildren();
if (numChildren != 1)
{
   throw new BaseException("Invalid number of arguments for 'log2' function: " + numChildren);
}
return Expressions.log2(Jep.nodeToExpression(node.jjtGetChild(0)));
      Parameters:
      node - The node representing this function
      Returns:
      An Expression object