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Diffstat (limited to 'libjava/classpath/java/awt/geom/Point2D.java')
| -rw-r--r-- | libjava/classpath/java/awt/geom/Point2D.java | 396 |
1 files changed, 396 insertions, 0 deletions
diff --git a/libjava/classpath/java/awt/geom/Point2D.java b/libjava/classpath/java/awt/geom/Point2D.java new file mode 100644 index 00000000000..9f22a5a67c9 --- /dev/null +++ b/libjava/classpath/java/awt/geom/Point2D.java @@ -0,0 +1,396 @@ +/* Point2D.java -- generic point in 2-D space + Copyright (C) 1999, 2000, 2002, 2004 Free Software Foundation + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package java.awt.geom; + +/** + * This class implements a generic point in 2D Cartesian space. The storage + * representation is left up to the subclass. Point includes two useful + * nested classes, for float and double storage respectively. + * + * @author Per Bothner (bothner@cygnus.com) + * @author Eric Blake (ebb9@email.byu.edu) + * @since 1.2 + * @status updated to 1.4 + */ +public abstract class Point2D implements Cloneable +{ + /** + * The default constructor. + * + * @see java.awt.Point + * @see Point2D.Float + * @see Point2D.Double + */ + protected Point2D() + { + } + + /** + * Get the X coordinate, in double precision. + * + * @return the x coordinate + */ + public abstract double getX(); + + /** + * Get the Y coordinate, in double precision. + * + * @return the y coordinate + */ + public abstract double getY(); + + /** + * Set the location of this point to the new coordinates. There may be a + * loss of precision. + * + * @param x the new x coordinate + * @param y the new y coordinate + */ + public abstract void setLocation(double x, double y); + + /** + * Set the location of this point to the new coordinates. There may be a + * loss of precision. + * + * @param p the point to copy + * @throws NullPointerException if p is null + */ + public void setLocation(Point2D p) + { + setLocation(p.getX(), p.getY()); + } + + /** + * Return the square of the distance between two points. + * + * @param x1 the x coordinate of point 1 + * @param y1 the y coordinate of point 1 + * @param x2 the x coordinate of point 2 + * @param y2 the y coordinate of point 2 + * @return (x2 - x1)^2 + (y2 - y1)^2 + */ + public static double distanceSq(double x1, double y1, double x2, double y2) + { + x2 -= x1; + y2 -= y1; + return x2 * x2 + y2 * y2; + } + + /** + * Return the distance between two points. + * + * @param x1 the x coordinate of point 1 + * @param y1 the y coordinate of point 1 + * @param x2 the x coordinate of point 2 + * @param y2 the y coordinate of point 2 + * @return the distance from (x1,y1) to (x2,y2) + */ + public static double distance(double x1, double y1, double x2, double y2) + { + return Math.sqrt(distanceSq(x1, y1, x2, y2)); + } + + /** + * Return the square of the distance from this point to the given one. + * + * @param x the x coordinate of the other point + * @param y the y coordinate of the other point + * @return the square of the distance + */ + public double distanceSq(double x, double y) + { + return distanceSq(getX(), x, getY(), y); + } + + /** + * Return the square of the distance from this point to the given one. + * + * @param p the other point + * @return the square of the distance + * @throws NullPointerException if p is null + */ + public double distanceSq(Point2D p) + { + return distanceSq(getX(), p.getX(), getY(), p.getY()); + } + + /** + * Return the distance from this point to the given one. + * + * @param x the x coordinate of the other point + * @param y the y coordinate of the other point + * @return the distance + */ + public double distance(double x, double y) + { + return distance(getX(), x, getY(), y); + } + + /** + * Return the distance from this point to the given one. + * + * @param p the other point + * @return the distance + * @throws NullPointerException if p is null + */ + public double distance(Point2D p) + { + return distance(getX(), p.getX(), getY(), p.getY()); + } + + /** + * Create a new point of the same run-time type with the same contents as + * this one. + * + * @return the clone + */ + public Object clone() + { + try + { + return super.clone(); + } + catch (CloneNotSupportedException e) + { + throw (Error) new InternalError().initCause(e); // Impossible + } + } + + /** + * Return the hashcode for this point. The formula is not documented, but + * appears to be the same as: + * <pre> + * long l = Double.doubleToLongBits(getY()); + * l = l * 31 ^ Double.doubleToLongBits(getX()); + * return (int) ((l >> 32) ^ l); + * </pre> + * + * @return the hashcode + */ + public int hashCode() + { + // Talk about a fun time reverse engineering this one! + long l = java.lang.Double.doubleToLongBits(getY()); + l = l * 31 ^ java.lang.Double.doubleToLongBits(getX()); + return (int) ((l >> 32) ^ l); + } + + /** + * Compares two points for equality. This returns true if they have the + * same coordinates. + * + * @param o the point to compare + * @return true if it is equal + */ + public boolean equals(Object o) + { + if (! (o instanceof Point2D)) + return false; + Point2D p = (Point2D) o; + return getX() == p.getX() && getY() == p.getY(); + } + + /** + * This class defines a point in <code>double</code> precision. + * + * @author Eric Blake (ebb9@email.byu.edu) + * @since 1.2 + * @status updated to 1.4 + */ + public static class Double extends Point2D + { + /** The X coordinate. */ + public double x; + + /** The Y coordinate. */ + public double y; + + /** + * Create a new point at (0,0). + */ + public Double() + { + } + + /** + * Create a new point at (x,y). + * + * @param x the x coordinate + * @param y the y coordinate + */ + public Double(double x, double y) + { + this.x = x; + this.y = y; + } + + /** + * Return the x coordinate. + * + * @return the x coordinate + */ + public double getX() + { + return x; + } + + /** + * Return the y coordinate. + * + * @return the y coordinate + */ + public double getY() + { + return y; + } + + /** + * Sets the location of this point. + * + * @param x the new x coordinate + * @param y the new y coordinate + */ + public void setLocation(double x, double y) + { + this.x = x; + this.y = y; + } + + /** + * Returns a string representation of this object. The format is: + * <code>"Point2D.Double[" + x + ", " + y + ']'</code>. + * + * @return a string representation of this object + */ + public String toString() + { + return "Point2D.Double[" + x + ", " + y + ']'; + } + } // class Double + + /** + * This class defines a point in <code>float</code> precision. + * + * @author Eric Blake (ebb9@email.byu.edu) + * @since 1.2 + * @status updated to 1.4 + */ + public static class Float extends Point2D + { + /** The X coordinate. */ + public float x; + + /** The Y coordinate. */ + public float y; + + /** + * Create a new point at (0,0). + */ + public Float() + { + } + + /** + * Create a new point at (x,y). + * + * @param x the x coordinate + * @param y the y coordinate + */ + public Float(float x, float y) + { + this.x = x; + this.y = y; + } + + /** + * Return the x coordinate. + * + * @return the x coordinate + */ + public double getX() + { + return x; + } + + /** + * Return the y coordinate. + * + * @return the y coordinate + */ + public double getY() + { + return y; + } + + /** + * Sets the location of this point. + * + * @param x the new x coordinate + * @param y the new y coordinate + */ + public void setLocation(double x, double y) + { + this.x = (float) x; + this.y = (float) y; + } + + /** + * Sets the location of this point. + * + * @param x the new x coordinate + * @param y the new y coordinate + */ + public void setLocation(float x, float y) + { + this.x = x; + this.y = y; + } + + /** + * Returns a string representation of this object. The format is: + * <code>"Point2D.Float[" + x + ", " + y + ']'</code>. + * + * @return a string representation of this object + */ + public String toString() + { + return "Point2D.Float[" + x + ", " + y + ']'; + } + } // class Float +} // class Point2D |
