boidslist.java

来自「java3D game engine design of the source 」· Java 代码 · 共 39 行

// BoidsList.java
// Andrew Davison, April 2005, [e-mail]
// Sirinart Sakarin, March 2003, [e-mail]


/* An ArrayList for boids. 
   The methods are synchronized so that boid removal cannot
   affect the retrieval of a reference to a boid.
*/

import java.util.*;

public class BoidsList extends ArrayList
{
  public BoidsList(int num)
  {  super(num);  }


  synchronized public Boid getBoid(int i)
  // return the boid if it is visible; null otherwise
  {
    if (i < super.size())
      return (Boid)get(i);
    return null;
  }


 synchronized public boolean removeBoid(int i)
 // attempt to remove the i'th boid
 { if (i < super.size()) {
      super.remove(i);
      return true;
   }
   return false;
 }


}  // end of BoidsList class