Java tutorial
/* * Copyright (c) 1995, 2008, 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.Dimension2D; import java.beans.Transient; /** * The {@code Dimension} class encapsulates the width and * height of a component (in integer precision) in a single object. * The class is * associated with certain properties of components. Several methods * defined by the {@code Component} class and the * {@code LayoutManager} interface return a * {@code Dimension} object. * <p> * Normally the values of {@code width} * and {@code height} are non-negative integers. * The constructors that allow you to create a dimension do * not prevent you from setting a negative value for these properties. * If the value of {@code width} or {@code height} is * negative, the behavior of some methods defined by other objects is * undefined. * * @author Sami Shaio * @author Arthur van Hoff * @see java.awt.Component * @see java.awt.LayoutManager * @since 1.0 */ public class Dimension extends Dimension2D implements java.io.Serializable { /** * The width dimension; negative values can be used. * * @serial * @see #getSize * @see #setSize * @since 1.0 */ public int width; /** * The height dimension; negative values can be used. * * @serial * @see #getSize * @see #setSize * @since 1.0 */ public int height; /* * JDK 1.1 serialVersionUID */ private static final long serialVersionUID = 4723952579491349524L; /** * 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(); } } /** * Creates an instance of {@code Dimension} with a width * of zero and a height of zero. */ public Dimension() { this(0, 0); } /** * Creates an instance of {@code Dimension} whose width * and height are the same as for the specified dimension. * * @param d the specified dimension for the * {@code width} and * {@code height} values */ public Dimension(Dimension d) { this(d.width, d.height); } /** * Constructs a {@code Dimension} and initializes * it to the specified width and specified height. * * @param width the specified width * @param height the specified height */ public Dimension(int width, int height) { this.width = width; this.height = height; } /** * {@inheritDoc} * @since 1.2 */ public double getWidth() { return width; } /** * {@inheritDoc} * @since 1.2 */ public double getHeight() { return height; } /** * Sets the size of this {@code Dimension} object to * the specified width and height in double precision. * Note that if {@code width} or {@code height} * are larger than {@code Integer.MAX_VALUE}, they will * be reset to {@code Integer.MAX_VALUE}. * * @param width the new width for the {@code Dimension} object * @param height the new height for the {@code Dimension} object * @since 1.2 */ public void setSize(double width, double height) { this.width = (int) Math.ceil(width); this.height = (int) Math.ceil(height); } /** * Gets the size of this {@code Dimension} object. * This method is included for completeness, to parallel the * {@code getSize} method defined by {@code Component}. * * @return the size of this dimension, a new instance of * {@code Dimension} with the same width and height * @see java.awt.Dimension#setSize * @see java.awt.Component#getSize * @since 1.1 */ @Transient public Dimension getSize() { return new Dimension(width, height); } /** * Sets the size of this {@code Dimension} object to the specified size. * This method is included for completeness, to parallel the * {@code setSize} method defined by {@code Component}. * @param d the new size for this {@code Dimension} object * @see java.awt.Dimension#getSize * @see java.awt.Component#setSize * @since 1.1 */ public void setSize(Dimension d) { setSize(d.width, d.height); } /** * Sets the size of this {@code Dimension} object * to the specified width and height. * This method is included for completeness, to parallel the * {@code setSize} method defined by {@code Component}. * * @param width the new width for this {@code Dimension} object * @param height the new height for this {@code Dimension} object * @see java.awt.Dimension#getSize * @see java.awt.Component#setSize * @since 1.1 */ public void setSize(int width, int height) { this.width = width; this.height = height; } /** * Checks whether two dimension objects have equal values. */ public boolean equals(Object obj) { if (obj instanceof Dimension) { Dimension d = (Dimension) obj; return (width == d.width) && (height == d.height); } return false; } /** * Returns the hash code for this {@code Dimension}. * * @return a hash code for this {@code Dimension} */ public int hashCode() { int sum = width + height; return sum * (sum + 1) / 2 + width; } /** * Returns a string representation of the values of this * {@code Dimension} object's {@code height} and * {@code width} fields. This method is intended to be used only * for debugging purposes, and the content and format of the returned * string may vary between implementations. The returned string may be * empty but may not be {@code null}. * * @return a string representation of this {@code Dimension} * object */ public String toString() { return getClass().getName() + "[width=" + width + ",height=" + height + "]"; } }