Java tutorial
/* * Copyright (c) 1995, 2017, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.awt; import java.awt.geom.Rectangle2D; import java.beans.Transient; /** * A {@code Rectangle} specifies an area in a coordinate space that is * enclosed by the {@code Rectangle} object's upper-left point * {@code (x,y)} * in the coordinate space, its width, and its height. * <p> * A {@code Rectangle} object's {@code width} and * {@code height} are {@code public} fields. The constructors * that create a {@code Rectangle}, and the methods that can modify * one, do not prevent setting a negative value for width or height. * <p> * <a id="Empty"> * A {@code Rectangle} whose width or height is exactly zero has location * along those axes with zero dimension, but is otherwise considered empty.</a> * The {@link #isEmpty} method will return true for such a {@code Rectangle}. * Methods which test if an empty {@code Rectangle} contains or intersects * a point or rectangle will always return false if either dimension is zero. * Methods which combine such a {@code Rectangle} with a point or rectangle * will include the location of the {@code Rectangle} on that axis in the * result as if the {@link #add(Point)} method were being called. * <p> * <a id="NonExistent"> * A {@code Rectangle} whose width or height is negative has neither * location nor dimension along those axes with negative dimensions. * Such a {@code Rectangle} is treated as non-existent along those axes. * Such a {@code Rectangle} is also empty with respect to containment * calculations and methods which test if it contains or intersects a * point or rectangle will always return false. * Methods which combine such a {@code Rectangle} with a point or rectangle * will ignore the {@code Rectangle} entirely in generating the result. * If two {@code Rectangle} objects are combined and each has a negative * dimension, the result will have at least one negative dimension. * </a> * <p> * Methods which affect only the location of a {@code Rectangle} will * operate on its location regardless of whether or not it has a negative * or zero dimension along either axis. * <p> * Note that a {@code Rectangle} constructed with the default no-argument * constructor will have dimensions of {@code 0x0} and therefore be empty. * That {@code Rectangle} will still have a location of {@code (0,0)} and * will contribute that location to the union and add operations. * Code attempting to accumulate the bounds of a set of points should * therefore initially construct the {@code Rectangle} with a specifically * negative width and height or it should use the first point in the set * to construct the {@code Rectangle}. * For example: * <pre>{@code * Rectangle bounds = new Rectangle(0, 0, -1, -1); * for (int i = 0; i < points.length; i++) { * bounds.add(points[i]); * } * }</pre> * or if we know that the points array contains at least one point: * <pre>{@code * Rectangle bounds = new Rectangle(points[0]); * for (int i = 1; i < points.length; i++) { * bounds.add(points[i]); * } * }</pre> * <p> * This class uses 32-bit integers to store its location and dimensions. * Frequently operations may produce a result that exceeds the range of * a 32-bit integer. * The methods will calculate their results in a way that avoids any * 32-bit overflow for intermediate results and then choose the best * representation to store the final results back into the 32-bit fields * which hold the location and dimensions. * The location of the result will be stored into the {@link #x} and * {@link #y} fields by clipping the true result to the nearest 32-bit value. * The values stored into the {@link #width} and {@link #height} dimension * fields will be chosen as the 32-bit values that encompass the largest * part of the true result as possible. * Generally this means that the dimension will be clipped independently * to the range of 32-bit integers except that if the location had to be * moved to store it into its pair of 32-bit fields then the dimensions * will be adjusted relative to the "best representation" of the location. * If the true result had a negative dimension and was therefore * non-existent along one or both axes, the stored dimensions will be * negative numbers in those axes. * If the true result had a location that could be represented within * the range of 32-bit integers, but zero dimension along one or both * axes, then the stored dimensions will be zero in those axes. * * @author Sami Shaio * @since 1.0 */ public class Rectangle extends Rectangle2D implements Shape, java.io.Serializable { /** * The X coordinate of the upper-left corner of the {@code Rectangle}. * * @serial * @see #setLocation(int, int) * @see #getLocation() * @since 1.0 */ public int x; /** * The Y coordinate of the upper-left corner of the {@code Rectangle}. * * @serial * @see #setLocation(int, int) * @see #getLocation() * @since 1.0 */ public int y; /** * The width of the {@code Rectangle}. * @serial * @see #setSize(int, int) * @see #getSize() * @since 1.0 */ public int width; /** * The height of the {@code Rectangle}. * * @serial * @see #setSize(int, int) * @see #getSize() * @since 1.0 */ public int height; /* * JDK 1.1 serialVersionUID */ private static final long serialVersionUID = -4345857070255674764L; /** * Initialize JNI field and method IDs */ private static native void initIDs(); static { /* ensure that the necessary native libraries are loaded */ Toolkit.loadLibraries(); if (!GraphicsEnvironment.isHeadless()) { initIDs(); } } /** * Constructs a new {@code Rectangle} whose upper-left corner * is at (0, 0) in the coordinate space, and whose width and * height are both zero. */ public Rectangle() { this(0, 0, 0, 0); } /** * Constructs a new {@code Rectangle}, initialized to match * the values of the specified {@code Rectangle}. * @param r the {@code Rectangle} from which to copy initial values * to a newly constructed {@code Rectangle} * @since 1.1 */ public Rectangle(Rectangle r) { this(r.x, r.y, r.width, r.height); } /** * Constructs a new {@code Rectangle} whose upper-left corner is * specified as * {@code (x,y)} and whose width and height * are specified by the arguments of the same name. * @param x the specified X coordinate * @param y the specified Y coordinate * @param width the width of the {@code Rectangle} * @param height the height of the {@code Rectangle} * @since 1.0 */ public Rectangle(int x, int y, int width, int height) { this.x = x; this.y = y; this.width = width; this.height = height; } /** * Constructs a new {@code Rectangle} whose upper-left corner * is at (0, 0) in the coordinate space, and whose width and * height are specified by the arguments of the same name. * @param width the width of the {@code Rectangle} * @param height the height of the {@code Rectangle} */ public Rectangle(int width, int height) { this(0, 0, width, height); } /** * Constructs a new {@code Rectangle} whose upper-left corner is * specified by the {@link Point} argument, and * whose width and height are specified by the * {@link Dimension} argument. * @param p a {@code Point} that is the upper-left corner of * the {@code Rectangle} * @param d a {@code Dimension}, representing the * width and height of the {@code Rectangle} */ public Rectangle(Point p, Dimension d) { this(p.x, p.y, d.width, d.height); } /** * Constructs a new {@code Rectangle} whose upper-left corner is the * specified {@code Point}, and whose width and height are both zero. * @param p a {@code Point} that is the top left corner * of the {@code Rectangle} */ public Rectangle(Point p) { this(p.x, p.y, 0, 0); } /** * Constructs a new {@code Rectangle} whose top left corner is * (0, 0) and whose width and height are specified * by the {@code Dimension} argument. * @param d a {@code Dimension}, specifying width and height */ public Rectangle(Dimension d) { this(0, 0, d.width, d.height); } /** * Returns the X coordinate of the bounding {@code Rectangle} in * {@code double} precision. * @return the X coordinate of the bounding {@code Rectangle}. */ public double getX() { return x; } /** * Returns the Y coordinate of the bounding {@code Rectangle} in * {@code double} precision. * @return the Y coordinate of the bounding {@code Rectangle}. */ public double getY() { return y; } /** * Returns the width of the bounding {@code Rectangle} in * {@code double} precision. * @return the width of the bounding {@code Rectangle}. */ public double getWidth() { return width; } /** * Returns the height of the bounding {@code Rectangle} in * {@code double} precision. * @return the height of the bounding {@code Rectangle}. */ public double getHeight() { return height; } /** * Gets the bounding {@code Rectangle} of this {@code Rectangle}. * <p> * This method is included for completeness, to parallel the * {@code getBounds} method of * {@link Component}. * @return a new {@code Rectangle}, equal to the * bounding {@code Rectangle} for this {@code Rectangle}. * @see java.awt.Component#getBounds * @see #setBounds(Rectangle) * @see #setBounds(int, int, int, int) * @since 1.1 */ @Transient public Rectangle getBounds() { return new Rectangle(x, y, width, height); } /** * {@inheritDoc} * @since 1.2 */ public Rectangle2D getBounds2D() { return new Rectangle(x, y, width, height); } /** * Sets the bounding {@code Rectangle} of this {@code Rectangle} * to match the specified {@code Rectangle}. * <p> * This method is included for completeness, to parallel the * {@code setBounds} method of {@code Component}. * @param r the specified {@code Rectangle} * @see #getBounds * @see java.awt.Component#setBounds(java.awt.Rectangle) * @since 1.1 */ public void setBounds(Rectangle r) { setBounds(r.x, r.y, r.width, r.height); } /** * Sets the bounding {@code Rectangle} of this * {@code Rectangle} to the specified * {@code x}, {@code y}, {@code width}, * and {@code height}. * <p> * This method is included for completeness, to parallel the * {@code setBounds} method of {@code Component}. * @param x the new X coordinate for the upper-left * corner of this {@code Rectangle} * @param y the new Y coordinate for the upper-left * corner of this {@code Rectangle} * @param width the new width for this {@code Rectangle} * @param height the new height for this {@code Rectangle} * @see #getBounds * @see java.awt.Component#setBounds(int, int, int, int) * @since 1.1 */ public void setBounds(int x, int y, int width, int height) { reshape(x, y, width, height); } /** * Sets the bounds of this {@code Rectangle} to the integer bounds * which encompass the specified {@code x}, {@code y}, {@code width}, * and {@code height}. * If the parameters specify a {@code Rectangle} that exceeds the * maximum range of integers, the result will be the best * representation of the specified {@code Rectangle} intersected * with the maximum integer bounds. * @param x the X coordinate of the upper-left corner of * the specified rectangle * @param y the Y coordinate of the upper-left corner of * the specified rectangle * @param width the width of the specified rectangle * @param height the new height of the specified rectangle */ public void setRect(double x, double y, double width, double height) { int newx, newy, neww, newh; if (x > 2.0 * Integer.MAX_VALUE) { // Too far in positive X direction to represent... // We cannot even reach the left side of the specified // rectangle even with both x & width set to MAX_VALUE. // The intersection with the "maximal integer rectangle" // is non-existent so we should use a width < 0. // REMIND: Should we try to determine a more "meaningful" // adjusted value for neww than just "-1"? newx = Integer.MAX_VALUE; neww = -1; } else { newx = clip(x, false); if (width >= 0) width += x - newx; neww = clip(width, width >= 0); } if (y > 2.0 * Integer.MAX_VALUE) { // Too far in positive Y direction to represent... newy = Integer.MAX_VALUE; newh = -1; } else { newy = clip(y, false); if (height >= 0) height += y - newy; newh = clip(height, height >= 0); } reshape(newx, newy, neww, newh); } // Return best integer representation for v, clipped to integer // range and floor-ed or ceiling-ed, depending on the boolean. private static int clip(double v, boolean doceil) { if (v <= Integer.MIN_VALUE) { return Integer.MIN_VALUE; } if (v >= Integer.MAX_VALUE) { return Integer.MAX_VALUE; } return (int) (doceil ? Math.ceil(v) : Math.floor(v)); } /** * Sets the bounding {@code Rectangle} of this * {@code Rectangle} to the specified * {@code x}, {@code y}, {@code width}, * and {@code height}. * * @param x the new X coordinate for the upper-left * corner of this {@code Rectangle} * @param y the new Y coordinate for the upper-left * corner of this {@code Rectangle} * @param width the new width for this {@code Rectangle} * @param height the new height for this {@code Rectangle} * @deprecated As of JDK version 1.1, * replaced by {@code setBounds(int, int, int, int)}. */ @Deprecated public void reshape(int x, int y, int width, int height) { this.x = x; this.y = y; this.width = width; this.height = height; } /** * Returns the location of this {@code Rectangle}. * <p> * This method is included for completeness, to parallel the * {@code getLocation} method of {@code Component}. * @return the {@code Point} that is the upper-left corner of * this {@code Rectangle}. * @see java.awt.Component#getLocation * @see #setLocation(Point) * @see #setLocation(int, int) * @since 1.1 */ public Point getLocation() { return new Point(x, y); } /** * Moves this {@code Rectangle} to the specified location. * <p> * This method is included for completeness, to parallel the * {@code setLocation} method of {@code Component}. * @param p the {@code Point} specifying the new location * for this {@code Rectangle} * @see java.awt.Component#setLocation(java.awt.Point) * @see #getLocation * @since 1.1 */ public void setLocation(Point p) { setLocation(p.x, p.y); } /** * Moves this {@code Rectangle} to the specified location. * <p> * This method is included for completeness, to parallel the * {@code setLocation} method of {@code Component}. * @param x the X coordinate of the new location * @param y the Y coordinate of the new location * @see #getLocation * @see java.awt.Component#setLocation(int, int) * @since 1.1 */ public void setLocation(int x, int y) { move(x, y); } /** * Moves this {@code Rectangle} to the specified location. * * @param x the X coordinate of the new location * @param y the Y coordinate of the new location * @deprecated As of JDK version 1.1, * replaced by {@code setLocation(int, int)}. */ @Deprecated public void move(int x, int y) { this.x = x; this.y = y; } /** * Translates this {@code Rectangle} the indicated distance, * to the right along the X coordinate axis, and * downward along the Y coordinate axis. * @param dx the distance to move this {@code Rectangle} * along the X axis * @param dy the distance to move this {@code Rectangle} * along the Y axis * @see java.awt.Rectangle#setLocation(int, int) * @see java.awt.Rectangle#setLocation(java.awt.Point) */ public void translate(int dx, int dy) { int oldv = this.x; int newv = oldv + dx; if (dx < 0) { // moving leftward if (newv > oldv) { // negative overflow // Only adjust width if it was valid (>= 0). if (width >= 0) { // The right edge is now conceptually at // newv+width, but we may move newv to prevent // overflow. But we want the right edge to // remain at its new location in spite of the // clipping. Think of the following adjustment // conceptually the same as: // width += newv; newv = MIN_VALUE; width -= newv; width += newv - Integer.MIN_VALUE; // width may go negative if the right edge went past // MIN_VALUE, but it cannot overflow since it cannot // have moved more than MIN_VALUE and any non-negative // number + MIN_VALUE does not overflow. } newv = Integer.MIN_VALUE; } } else { // moving rightward (or staying still) if (newv < oldv) { // positive overflow if (width >= 0) { // Conceptually the same as: // width += newv; newv = MAX_VALUE; width -= newv; width += newv - Integer.MAX_VALUE; // With large widths and large displacements // we may overflow so we need to check it. if (width < 0) width = Integer.MAX_VALUE; } newv = Integer.MAX_VALUE; } } this.x = newv; oldv = this.y; newv = oldv + dy; if (dy < 0) { // moving upward if (newv > oldv) { // negative overflow if (height >= 0) { height += newv - Integer.MIN_VALUE; // See above comment about no overflow in this case } newv = Integer.MIN_VALUE; } } else { // moving downward (or staying still) if (newv < oldv) { // positive overflow if (height >= 0) { height += newv - Integer.MAX_VALUE; if (height < 0) height = Integer.MAX_VALUE; } newv = Integer.MAX_VALUE; } } this.y = newv; } /** * Gets the size of this {@code Rectangle}, represented by * the returned {@code Dimension}. * <p> * This method is included for completeness, to parallel the * {@code getSize} method of {@code Component}. * @return a {@code Dimension}, representing the size of * this {@code Rectangle}. * @see java.awt.Component#getSize * @see #setSize(Dimension) * @see #setSize(int, int) * @since 1.1 */ public Dimension getSize() { return new Dimension(width, height); } /** * Sets the size of this {@code Rectangle} to match the * specified {@code Dimension}. * <p> * This method is included for completeness, to parallel the * {@code setSize} method of {@code Component}. * @param d the new size for the {@code Dimension} object * @see java.awt.Component#setSize(java.awt.Dimension) * @see #getSize * @since 1.1 */ public void setSize(Dimension d) { setSize(d.width, d.height); } /** * Sets the size of this {@code Rectangle} to the specified * width and height. * <p> * This method is included for completeness, to parallel the * {@code setSize} method of {@code Component}. * @param width the new width for this {@code Rectangle} * @param height the new height for this {@code Rectangle} * @see java.awt.Component#setSize(int, int) * @see #getSize * @since 1.1 */ public void setSize(int width, int height) { resize(width, height); } /** * Sets the size of this {@code Rectangle} to the specified * width and height. * * @param width the new width for this {@code Rectangle} * @param height the new height for this {@code Rectangle} * @deprecated As of JDK version 1.1, * replaced by {@code setSize(int, int)}. */ @Deprecated public void resize(int width, int height) { this.width = width; this.height = height; } /** * Checks whether or not this {@code Rectangle} contains the * specified {@code Point}. * @param p the {@code Point} to test * @return {@code true} if the specified {@code Point} * is inside this {@code Rectangle}; * {@code false} otherwise. * @since 1.1 */ public boolean contains(Point p) { return contains(p.x, p.y); } /** * Checks whether or not this {@code Rectangle} contains the * point at the specified location {@code (x,y)}. * * @param x the specified X coordinate * @param y the specified Y coordinate * @return {@code true} if the point * {@code (x,y)} is inside this * {@code Rectangle}; * {@code false} otherwise. * @since 1.1 */ public boolean contains(int x, int y) { return inside(x, y); } /** * Checks whether or not this {@code Rectangle} entirely contains * the specified {@code Rectangle}. * * @param r the specified {@code Rectangle} * @return {@code true} if the {@code Rectangle} * is contained entirely inside this {@code Rectangle}; * {@code false} otherwise * @since 1.2 */ public boolean contains(Rectangle r) { return contains(r.x, r.y, r.width, r.height); } /** * Checks whether this {@code Rectangle} entirely contains * the {@code Rectangle} * at the specified location {@code (X,Y)} with the * specified dimensions {@code (W,H)}. * @param X the specified X coordinate * @param Y the specified Y coordinate * @param W the width of the {@code Rectangle} * @param H the height of the {@code Rectangle} * @return {@code true} if the {@code Rectangle} specified by * {@code (X, Y, W, H)} * is entirely enclosed inside this {@code Rectangle}; * {@code false} otherwise. * @since 1.1 */ public boolean contains(int X, int Y, int W, int H) { int w = this.width; int h = this.height; if ((w | h | W | H) < 0) { // At least one of the dimensions is negative... return false; } // Note: if any dimension is zero, tests below must return false... int x = this.x; int y = this.y; if (X < x || Y < y) { return false; } w += x; W += X; if (W <= X) { // X+W overflowed or W was zero, return false if... // either original w or W was zero or // x+w did not overflow or // the overflowed x+w is smaller than the overflowed X+W if (w >= x || W > w) return false; } else { // X+W did not overflow and W was not zero, return false if... // original w was zero or // x+w did not overflow and x+w is smaller than X+W if (w >= x && W > w) return false; } h += y; H += Y; if (H <= Y) { if (h >= y || H > h) return false; } else { if (h >= y && H > h) return false; } return true; } /** * Checks whether or not this {@code Rectangle} contains the * point at the specified location {@code (X,Y)}. * * @param X the specified X coordinate * @param Y the specified Y coordinate * @return {@code true} if the point * {@code (X,Y)} is inside this * {@code Rectangle}; * {@code false} otherwise. * @deprecated As of JDK version 1.1, * replaced by {@code contains(int, int)}. */ @Deprecated public boolean inside(int X, int Y) { int w = this.width; int h = this.height; if ((w | h) < 0) { // At least one of the dimensions is negative... return false; } // Note: if either dimension is zero, tests below must return false... int x = this.x; int y = this.y; if (X < x || Y < y) { return false; } w += x; h += y; // overflow || intersect return ((w < x || w > X) && (h < y || h > Y)); } /** * Determines whether or not this {@code Rectangle} and the specified * {@code Rectangle} intersect. Two rectangles intersect if * their intersection is nonempty. * * @param r the specified {@code Rectangle} * @return {@code true} if the specified {@code Rectangle} * and this {@code Rectangle} intersect; * {@code false} otherwise. */ public boolean intersects(Rectangle r) { int tw = this.width; int th = this.height; int rw = r.width; int rh = r.height; if (rw <= 0 || rh <= 0 || tw <= 0 || th <= 0) { return false; } int tx = this.x; int ty = this.y; int rx = r.x; int ry = r.y; rw += rx; rh += ry; tw += tx; th += ty; // overflow || intersect return ((rw < rx || rw > tx) && (rh < ry || rh > ty) && (tw < tx || tw > rx) && (th < ty || th > ry)); } /** * Computes the intersection of this {@code Rectangle} with the * specified {@code Rectangle}. Returns a new {@code Rectangle} * that represents the intersection of the two rectangles. * If the two rectangles do not intersect, the result will be * an empty rectangle. * * @param r the specified {@code Rectangle} * @return the largest {@code Rectangle} contained in both the * specified {@code Rectangle} and in * this {@code Rectangle}; or if the rectangles * do not intersect, an empty rectangle. */ public Rectangle intersection(Rectangle r) { int tx1 = this.x; int ty1 = this.y; int rx1 = r.x; int ry1 = r.y; long tx2 = tx1; tx2 += this.width; long ty2 = ty1; ty2 += this.height; long rx2 = rx1; rx2 += r.width; long ry2 = ry1; ry2 += r.height; if (tx1 < rx1) tx1 = rx1; if (ty1 < ry1) ty1 = ry1; if (tx2 > rx2) tx2 = rx2; if (ty2 > ry2) ty2 = ry2; tx2 -= tx1; ty2 -= ty1; // tx2,ty2 will never overflow (they will never be // larger than the smallest of the two source w,h) // they might underflow, though... if (tx2 < Integer.MIN_VALUE) tx2 = Integer.MIN_VALUE; if (ty2 < Integer.MIN_VALUE) ty2 = Integer.MIN_VALUE; return new Rectangle(tx1, ty1, (int) tx2, (int) ty2); } /** * Computes the union of this {@code Rectangle} with the * specified {@code Rectangle}. Returns a new * {@code Rectangle} that * represents the union of the two rectangles. * <p> * If either {@code Rectangle} has any dimension less than zero * the rules for <a href=#NonExistent>non-existent</a> rectangles * apply. * If only one has a dimension less than zero, then the result * will be a copy of the other {@code Rectangle}. * If both have dimension less than zero, then the result will * have at least one dimension less than zero. * <p> * If the resulting {@code Rectangle} would have a dimension * too large to be expressed as an {@code int}, the result * will have a dimension of {@code Integer.MAX_VALUE} along * that dimension. * @param r the specified {@code Rectangle} * @return the smallest {@code Rectangle} containing both * the specified {@code Rectangle} and this * {@code Rectangle}. */ public Rectangle union(Rectangle r) { long tx2 = this.width; long ty2 = this.height; if ((tx2 | ty2) < 0) { // This rectangle has negative dimensions... // If r has non-negative dimensions then it is the answer. // If r is non-existent (has a negative dimension), then both // are non-existent and we can return any non-existent rectangle // as an answer. Thus, returning r meets that criterion. // Either way, r is our answer. return new Rectangle(r); } long rx2 = r.width; long ry2 = r.height; if ((rx2 | ry2) < 0) { return new Rectangle(this); } int tx1 = this.x; int ty1 = this.y; tx2 += tx1; ty2 += ty1; int rx1 = r.x; int ry1 = r.y; rx2 += rx1; ry2 += ry1; if (tx1 > rx1) tx1 = rx1; if (ty1 > ry1) ty1 = ry1; if (tx2 < rx2) tx2 = rx2; if (ty2 < ry2) ty2 = ry2; tx2 -= tx1; ty2 -= ty1; // tx2,ty2 will never underflow since both original rectangles // were already proven to be non-empty // they might overflow, though... if (tx2 > Integer.MAX_VALUE) tx2 = Integer.MAX_VALUE; if (ty2 > Integer.MAX_VALUE) ty2 = Integer.MAX_VALUE; return new Rectangle(tx1, ty1, (int) tx2, (int) ty2); } /** * Adds a point, specified by the integer arguments {@code newx,newy} * to the bounds of this {@code Rectangle}. * <p> * If this {@code Rectangle} has any dimension less than zero, * the rules for <a href=#NonExistent>non-existent</a> * rectangles apply. * In that case, the new bounds of this {@code Rectangle} will * have a location equal to the specified coordinates and * width and height equal to zero. * <p> * After adding a point, a call to {@code contains} with the * added point as an argument does not necessarily return * {@code true}. The {@code contains} method does not * return {@code true} for points on the right or bottom * edges of a {@code Rectangle}. Therefore, if the added point * falls on the right or bottom edge of the enlarged * {@code Rectangle}, {@code contains} returns * {@code false} for that point. * If the specified point must be contained within the new * {@code Rectangle}, a 1x1 rectangle should be added instead: * <pre> * r.add(newx, newy, 1, 1); * </pre> * @param newx the X coordinate of the new point * @param newy the Y coordinate of the new point */ public void add(int newx, int newy) { if ((width | height) < 0) { this.x = newx; this.y = newy; this.width = this.height = 0; return; } int x1 = this.x; int y1 = this.y; long x2 = this.width; long y2 = this.height; x2 += x1; y2 += y1; if (x1 > newx) x1 = newx; if (y1 > newy) y1 = newy; if (x2 < newx) x2 = newx; if (y2 < newy) y2 = newy; x2 -= x1; y2 -= y1; if (x2 > Integer.MAX_VALUE) x2 = Integer.MAX_VALUE; if (y2 > Integer.MAX_VALUE) y2 = Integer.MAX_VALUE; reshape(x1, y1, (int) x2, (int) y2); } /** * Adds the specified {@code Point} to the bounds of this * {@code Rectangle}. * <p> * If this {@code Rectangle} has any dimension less than zero, * the rules for <a href=#NonExistent>non-existent</a> * rectangles apply. * In that case, the new bounds of this {@code Rectangle} will * have a location equal to the coordinates of the specified * {@code Point} and width and height equal to zero. * <p> * After adding a {@code Point}, a call to {@code contains} * with the added {@code Point} as an argument does not * necessarily return {@code true}. The {@code contains} * method does not return {@code true} for points on the right * or bottom edges of a {@code Rectangle}. Therefore if the added * {@code Point} falls on the right or bottom edge of the * enlarged {@code Rectangle}, {@code contains} returns * {@code false} for that {@code Point}. * If the specified point must be contained within the new * {@code Rectangle}, a 1x1 rectangle should be added instead: * <pre> * r.add(pt.x, pt.y, 1, 1); * </pre> * @param pt the new {@code Point} to add to this * {@code Rectangle} */ public void add(Point pt) { add(pt.x, pt.y); } /** * Adds a {@code Rectangle} to this {@code Rectangle}. * The resulting {@code Rectangle} is the union of the two * rectangles. * <p> * If either {@code Rectangle} has any dimension less than 0, the * result will have the dimensions of the other {@code Rectangle}. * If both {@code Rectangle}s have at least one dimension less * than 0, the result will have at least one dimension less than 0. * <p> * If either {@code Rectangle} has one or both dimensions equal * to 0, the result along those axes with 0 dimensions will be * equivalent to the results obtained by adding the corresponding * origin coordinate to the result rectangle along that axis, * similar to the operation of the {@link #add(Point)} method, * but contribute no further dimension beyond that. * <p> * If the resulting {@code Rectangle} would have a dimension * too large to be expressed as an {@code int}, the result * will have a dimension of {@code Integer.MAX_VALUE} along * that dimension. * @param r the specified {@code Rectangle} */ public void add(Rectangle r) { long tx2 = this.width; long ty2 = this.height; if ((tx2 | ty2) < 0) { reshape(r.x, r.y, r.width, r.height); } long rx2 = r.width; long ry2 = r.height; if ((rx2 | ry2) < 0) { return; } int tx1 = this.x; int ty1 = this.y; tx2 += tx1; ty2 += ty1; int rx1 = r.x; int ry1 = r.y; rx2 += rx1; ry2 += ry1; if (tx1 > rx1) tx1 = rx1; if (ty1 > ry1) ty1 = ry1; if (tx2 < rx2) tx2 = rx2; if (ty2 < ry2) ty2 = ry2; tx2 -= tx1; ty2 -= ty1; // tx2,ty2 will never underflow since both original // rectangles were non-empty // they might overflow, though... if (tx2 > Integer.MAX_VALUE) tx2 = Integer.MAX_VALUE; if (ty2 > Integer.MAX_VALUE) ty2 = Integer.MAX_VALUE; reshape(tx1, ty1, (int) tx2, (int) ty2); } /** * Resizes the {@code Rectangle} both horizontally and vertically. * <p> * This method modifies the {@code Rectangle} so that it is * {@code h} units larger on both the left and right side, * and {@code v} units larger at both the top and bottom. * <p> * The new {@code Rectangle} has {@code (x - h, y - v)} * as its upper-left corner, * width of {@code (width + 2h)}, * and a height of {@code (height + 2v)}. * <p> * If negative values are supplied for {@code h} and * {@code v}, the size of the {@code Rectangle} * decreases accordingly. * The {@code grow} method will check for integer overflow * and underflow, but does not check whether the resulting * values of {@code width} and {@code height} grow * from negative to non-negative or shrink from non-negative * to negative. * @param h the horizontal expansion * @param v the vertical expansion */ public void grow(int h, int v) { long x0 = this.x; long y0 = this.y; long x1 = this.width; long y1 = this.height; x1 += x0; y1 += y0; x0 -= h; y0 -= v; x1 += h; y1 += v; if (x1 < x0) { // Non-existent in X direction // Final width must remain negative so subtract x0 before // it is clipped so that we avoid the risk that the clipping // of x0 will reverse the ordering of x0 and x1. x1 -= x0; if (x1 < Integer.MIN_VALUE) x1 = Integer.MIN_VALUE; if (x0 < Integer.MIN_VALUE) x0 = Integer.MIN_VALUE; else if (x0 > Integer.MAX_VALUE) x0 = Integer.MAX_VALUE; } else { // (x1 >= x0) // Clip x0 before we subtract it from x1 in case the clipping // affects the representable area of the rectangle. if (x0 < Integer.MIN_VALUE) x0 = Integer.MIN_VALUE; else if (x0 > Integer.MAX_VALUE) x0 = Integer.MAX_VALUE; x1 -= x0; // The only way x1 can be negative now is if we clipped // x0 against MIN and x1 is less than MIN - in which case // we want to leave the width negative since the result // did not intersect the representable area. if (x1 < Integer.MIN_VALUE) x1 = Integer.MIN_VALUE; else if (x1 > Integer.MAX_VALUE) x1 = Integer.MAX_VALUE; } if (y1 < y0) { // Non-existent in Y direction y1 -= y0; if (y1 < Integer.MIN_VALUE) y1 = Integer.MIN_VALUE; if (y0 < Integer.MIN_VALUE) y0 = Integer.MIN_VALUE; else if (y0 > Integer.MAX_VALUE) y0 = Integer.MAX_VALUE; } else { // (y1 >= y0) if (y0 < Integer.MIN_VALUE) y0 = Integer.MIN_VALUE; else if (y0 > Integer.MAX_VALUE) y0 = Integer.MAX_VALUE; y1 -= y0; if (y1 < Integer.MIN_VALUE) y1 = Integer.MIN_VALUE; else if (y1 > Integer.MAX_VALUE) y1 = Integer.MAX_VALUE; } reshape((int) x0, (int) y0, (int) x1, (int) y1); } /** * {@inheritDoc} * @since 1.2 */ public boolean isEmpty() { return (width <= 0) || (height <= 0); } /** * {@inheritDoc} * @since 1.2 */ public int outcode(double x, double y) { /* * Note on casts to double below. If the arithmetic of * x+w or y+h is done in int, then we may get integer * overflow. By converting to double before the addition * we force the addition to be carried out in double to * avoid overflow in the comparison. * * See bug 4320890 for problems that this can cause. */ int out = 0; if (this.width <= 0) { out |= OUT_LEFT | OUT_RIGHT; } else if (x < this.x) { out |= OUT_LEFT; } else if (x > this.x + (double) this.width) { out |= OUT_RIGHT; } if (this.height <= 0) { out |= OUT_TOP | OUT_BOTTOM; } else if (y < this.y) { out |= OUT_TOP; } else if (y > this.y + (double) this.height) { out |= OUT_BOTTOM; } return out; } /** * {@inheritDoc} * @since 1.2 */ public Rectangle2D createIntersection(Rectangle2D r) { if (r instanceof Rectangle) { return intersection((Rectangle) r); } Rectangle2D dest = new Rectangle2D.Double(); Rectangle2D.intersect(this, r, dest); return dest; } /** * {@inheritDoc} * @since 1.2 */ public Rectangle2D createUnion(Rectangle2D r) { if (r instanceof Rectangle) { return union((Rectangle) r); } Rectangle2D dest = new Rectangle2D.Double(); Rectangle2D.union(this, r, dest); return dest; } /** * Checks whether two rectangles are equal. * <p> * The result is {@code true} if and only if the argument is not * {@code null} and is a {@code Rectangle} object that has the * same upper-left corner, width, and height as * this {@code Rectangle}. * @param obj the {@code Object} to compare with * this {@code Rectangle} * @return {@code true} if the objects are equal; * {@code false} otherwise. */ public boolean equals(Object obj) { if (obj instanceof Rectangle) { Rectangle r = (Rectangle) obj; return ((x == r.x) && (y == r.y) && (width == r.width) && (height == r.height)); } return super.equals(obj); } /** * Returns a {@code String} representing this * {@code Rectangle} and its values. * @return a {@code String} representing this * {@code Rectangle} object's coordinate and size values. */ public String toString() { return getClass().getName() + "[x=" + x + ",y=" + y + ",width=" + width + ",height=" + height + "]"; } }