Initializing java.awt.geom.Point2D

awt, java, swing

Solution

You use a static reference like this.

for (int i=0; i<coords.size(); ++i){
    newCoords=coords.elementAt(i);
    displayParams.displayCoords.add(new Point2D.Double(newCoords.getX(), yMax-newCoords.getY()));
}

This will create a new Point2D and leave our newCoords (element in the array) object unchanged.

Problem

I am developing using Java SE on NetBeans 7.3.1 on Windows 7. I write the following code. ``` import java.awt.geom.Point2D; static void setDisplayParams(Vector<Point2D> coords, double xMin, double xMax, double yMin, double yMax){ Point2D newCoords, oldCoords; Vector<Point2D> displayCoords = new Vector<Point2D>(); for (int i=0; i<coords.size(); ++i){ oldCoords=coords.elementAt(i); newCoords.setLocation(oldCoords.getX(), yMax-oldCoords.getY()); displayCoords.add(newCoords); } } ``` At the line ``` newCoords.setLocation(oldCoords.getX(), yMax-oldCoords.getY()); ``` I get the message ``` variable newCoords might not have been initialzed ``` I Googled ``` java.awt.geom.Point2D initializing java ``` and read here that ``` Point2D.Double() ``` is supposed to initialize a java.awt.geom.Point2D variable. However newCoords does not have a field Double. My for loop was initially ``` for (int i=0; i<coords.size(); ++i){ newCoords=coords.elementAt(i); newCoords.setLocation(newCoords.getX(), yMax-newCoords.getY()); displayParams.displayCoords.add(newCoords); } ``` This did not give me any error messages but it changed the values in coords which I do not want to do.

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