sim.util
Class Int2D
java.lang.Object
sim.util.Int2D
- All Implemented Interfaces:
- java.io.Serializable
- public final class Int2D
- extends java.lang.Object
- implements java.io.Serializable
Int2D is more or less the same class as java.awt.Point, but it is immutable: once the x and y values are set, they cannot be changed (they're final). Why use this immutable class when you could just use Point? Because Point is broken with respect to hash tables. You use Point as a key in a hash table at your own peril. Try this: hash an object by a Point as key. Then change the x value of the original Point. Ta-da! The object is lost in the hash table.
One day in the far future, Int2D should also be HIGHLY efficient; since it is immutable, it can be passed by value rather than by pointer by a smart compiler. Not today, though. But it's not bad.
This class has an elaborate hash code generation that is much more random than Sun's standard generator, but takes more time. For very large numbers of objects, this is a good idea, but we may change it to a simpler version in the future.
Int2D.equals(...) can compare by value against other Int2Ds and Double2Ds.
- See Also:
- Serialized Form
Field Summary |
int |
x
|
int |
y
|
Methods inherited from class java.lang.Object |
clone, finalize, getClass, notify, notifyAll, wait, wait, wait |
x
public final int x
y
public final int y
Int2D
public Int2D()
Int2D
public Int2D(java.awt.Point p)
Int2D
public Int2D(int x,
int y)
getX
public final int getX()
getY
public final int getY()
getPoint
public final java.awt.Point getPoint()
toString
public java.lang.String toString()
toCoordinates
public java.lang.String toCoordinates()
hashCodeFor
public static final int hashCodeFor(int x,
int y)
hashCode
public final int hashCode()
equals
public final boolean equals(java.lang.Object obj)