Package org.ddolib.ddo.core

Record Class Decision

java.lang.Object
java.lang.Record
org.ddolib.ddo.core.Decision
public record Decision(int variable, int value) extends Record
Represents a single decision within an optimization problem.

A Decision associates a variable identifier with a specific value. It is an immutable data structure that captures a single assignment performed during the search or compilation of a decision diagram (e.g., in an MDD-based solver).

Example:


 Decision d = new Decision(2, 5);
 System.out.println(d); // prints: Decision[variable=4, value=2]

Use in DD-based solvers:

  • Encapsulates the assignment of a value to a variable during branching.
  • Used to reconstruct solutions from paths in the decision diagram.
  • Acts as a key element in comparing or storing decision paths in sets and maps.

  • Constructor Summary

    Constructors
    Constructor
    Description
    Decision(int variable, int value)
    Creates an instance of a Decision record class.

  • Method Summary

    Modifier and Type
    Method
    Description
    final boolean
    equals(Object o)
    Indicates whether some other object is "equal to" this one.
    final int
    hashCode()
    Returns a hash code value for this object.
    final String
    toString()
    Returns a string representation of this record class.
    int
    value()
    Returns the value of the value record component.
    int
    variable()
    Returns the value of the variable record component.

    Methods inherited from class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait

  • Constructor Details

    • Decision

      public Decision(int variable, int value)
      Creates an instance of a Decision record class.
      Parameters:
      variable - the value for the variable record component
      value - the value for the value record component

  • Method Details

    • toString

      public final String toString()
      Returns a string representation of this record class. The representation contains the name of the class, followed by the name and value of each of the record components.
      Specified by:
      toString in class Record
      Returns:
      a string representation of this object

    • hashCode

      public final int hashCode()
      Returns a hash code value for this object. The value is derived from the hash code of each of the record components.
      Specified by:
      hashCode in class Record
      Returns:
      a hash code value for this object

    • equals

      public final boolean equals(Object o)
      Indicates whether some other object is "equal to" this one. The objects are equal if the other object is of the same class and if all the record components are equal. All components in this record class are compared with '=='.
      Specified by:
      equals in class Record
      Parameters:
      o - the object with which to compare
      Returns:
      true if this object is the same as the o argument; false otherwise.

    • variable

      public int variable()
      Returns the value of the variable record component.
      Returns:
      the value of the variable record component

    • value

      public int value()
      Returns the value of the value record component.
      Returns:
      the value of the value record component