Package net.sf.basedb.util.jep

Class LeftFunction

java.lang.Object
net.sf.basedb.util.jep.LeftFunction
All Implemented Interfaces:
JepFunction, org.nfunk.jep.function.PostfixMathCommandI
public class LeftFunction extends Object implements JepFunction
Adds a left(string, index|string) function to Jep. It is used to cut out the leftmost characters of a string. If the second argument is a number, the string is cut with String.substring(int, int) with 0 as the first argument. If the second argument is a string, the position of that string is looked up in the first string and is used as an index. Example: 
left('foo:bar', 3) == 'foo'
left('foo:bar', ':') == 'foo')
If the second variant is used and the second string is not found within the first, the first string is returned unmodified.
Since:
3.0
Author:
nicklas
Last modified
$Date $

  • Constructor Details

    • LeftFunction

      public LeftFunction()

  • 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 "left"
      See Also:

    • getNumberOfParameters

      public int getNumberOfParameters()
      Specified by:
      getNumberOfParameters in interface org.nfunk.jep.function.PostfixMathCommandI
      Returns:
      Always 2

    • setCurNumberOfParameters

      public void setCurNumberOfParameters(int n)
      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