Dimension.java

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package java.awt;

import java.awt.geom.Dimension2D;
import java.beans.Transient;
import java.io.Serial;

/**
 * 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;

    /**
     * Use serialVersionUID from JDK 1.1 for interoperability.
     */
     @Serial
     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 + "]";
    }
}