Define if statement conditions by pairs, and on only one parameter of an object

Question

I have created a digraph using the jgrapht library, and my vertices are Point objects:

public static class Point {

  public int x;
  public int y;
  public String type;

  public  Point(int x, int y, String type) 
  {

    this.x = x;
    this.y = y;
    this.type = type;
  }
  @Override
    public String toString() {
    return ("[x="+x+" y="+y+" type="+type+ "]");
  }

  @Override
    public int hashCode() {
    int hash = 7;
    hash = 71 * hash + this.x;
    hash = 71 * hash + this.y;

    return hash;
  }



  @Override
    public boolean equals(Object other) 
  {
    if (this == other)
      return true;

    if (!(other instanceof Point))
      return false;

    Point otherPoint = (Point) other;
    return otherPoint.x == x && otherPoint.y == y;
  }
}

I can go through all my vertices and get the successor of each point like this:*

 for (Point myPoint : directedGraph.vertexSet ()) {
      for (Point successor : Graphs.successorListOf (directedGraph, myPoint)){
 // Add if statement
 }
}

I need to define an if statement's conditions by pairs, but only on one or two of the Point parameters. For example, is these are my points:

public static Point startPoint = new Point(2, 6, "A");
public static Point firstPoint = new Point(2, 7, "A");
public static Point secondPoint = new Point(2, 8, "B");
public static Point thirdPoint = new Point(2, 9, "B");
public static Point fourthPoint = new Point(2, 10, "B");
public static Point fifthPoint = new Point(3, 7, "C");
public static Point sixthPoint = new Point(4, 7, "C");
public static Point seventhPoint = new Point(5, 7, "C");

I'd like to have a condition to be sure that myPoint and successor does not have particular "type":

for (Point myPoint : directedGraph.vertexSet ()) {
          for (Point successor : Graphs.successorListOf (directedGraph, myPoint)){
     if ((myPoint,successor) != (myPoint.type.equals("A"), successos.type.equals("B") && (myPoint,successor)!= (myPoint.type.equals("A"), successos.type.equals("C")){
// Do what I want
      } 
     }
    }

So what I'd need is to put a condition on a couple of points, but only on one parameter of my Point objects [the couple (myPoint and successor) can't be respectively (type A and type B) and (type A and type C).

Is this possible to do it this way ? I couldn't find any resources on this (and had trouble formulating my question so it didn't help)

score 1 · Accepted Answer · edited May 23 '17 at 12:30

look into javatuples you could make your own as described in this post https://stackoverflow.com/a/10631692/3944563

But it may not look pretty. you would be doing something similar to this,

//define your tuple class
class myTuple
{
 final String T1;
 final String T2;
 public myTuple(String t1, String t2)
{
  T1 = t1;
  T2 = t2;
}

if(myTupple(myPoint.type, successos.type) == myTupple("A", "B"))
{ /* do something */ }`

anyway, i dont think you can make it pretty, but you get the idea.

What i would do is add a static method to that class called "validateType" or whatever, and pass the two points and to your check in there

Define if statement conditions by pairs, and on only one parameter of an object

1 Answers1