Class UserConstant<T>

java.lang.Object
uk.ac.starlink.topcat.UserConstant<T>
All Implemented Interfaces:
uk.ac.starlink.ttools.jel.Constant<T>
public class UserConstant<T> extends Object implements uk.ac.starlink.ttools.jel.Constant<T>
Named JEL value that can be set by users for use in expressions. This is constant in the sense that it does not vary with row index, but its value can be changed by the user.
Since:
30 Jun 2025
Author:
Mark Taylor

  • Constructor Details

    • UserConstant

      public UserConstant(Class<T> clazz, String name, T value)
      Constructor.
      Parameters:
      clazz - value type
      name - constant name for use in JEL expressions
      value - initial value

  • Method Details

    • getContentClass

      public Class<T> getContentClass()
      Returns the value type for this constant.
      Specified by:
      getContentClass in interface uk.ac.starlink.ttools.jel.Constant<T>
      Returns:
      class

    • getName

      public String getName()
      Returns the name of this constant.
      Returns:
      name as used in JEL expressions

    • setName

      public void setName(String name)
      Sets the name of this constant.
      Parameters:
      name - new name

    • getValue

      public T getValue()
      Returns the value of this constant.
      Specified by:
      getValue in interface uk.ac.starlink.ttools.jel.Constant<T>
      Returns:
      current value

    • setValue

      public void setValue(T value)
      Sets the value of this constant.
      Parameters:
      value - new value

    • requiresRowIndex

      public boolean requiresRowIndex()
      returns false
      Specified by:
      requiresRowIndex in interface uk.ac.starlink.ttools.jel.Constant<T>

    • toString

      public String toString()
      Overrides:
      toString in class Object