/*
* Copyright (c) 2015, 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
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*/
package java.awt.image;
import java.awt.Image;
import java.util.List;
import java.util.Arrays;
import java.util.Collections;
import java.util.Objects;
/**
* This class is an array-based implementation of
* the {@code AbstractMultiResolutionImage} class.
*
* This class will implement the
* {@code getResolutionVariant(double destImageWidth, double destImageHeight)}
* method using a simple algorithm which will return the first image variant
* in the array that is large enough to satisfy the rendering request. The
* last image in the array will be returned if no suitable image is found
* that is as large as the rendering request.
* <p>
* For best effect the array of images should be sorted with each image being
* both wider and taller than the previous image. The base image need not be
* the first image in the array. No exception will be thrown if the images
* are not sorted as suggested.
*
* @see java.awt.Image
* @see java.awt.image.MultiResolutionImage
* @see java.awt.image.AbstractMultiResolutionImage
*
* @since 9
*/
public class BaseMultiResolutionImage extends AbstractMultiResolutionImage {
private final int baseImageIndex;
private final Image[] resolutionVariants;
/**
* Creates a multi-resolution image with the given resolution variants.
* The first resolution variant is used as the base image.
*
* @param resolutionVariants array of resolution variants sorted by image size
* @throws IllegalArgumentException if null or zero-length array is passed
* @throws NullPointerException if the specified {@code resolutionVariants}
* contains one or more null elements
*
* @since 9
*/
public BaseMultiResolutionImage(Image... resolutionVariants) {
this(0, resolutionVariants);
}
/**
* Creates a multi-resolution image with the given base image index and
* resolution variants.
*
* @param baseImageIndex the index of base image in the resolution variants
* array
* @param resolutionVariants array of resolution variants sorted by image size
* @throws IllegalArgumentException if null or zero-length array is passed
* @throws NullPointerException if the specified {@code resolutionVariants}
* contains one or more null elements
* @throws IndexOutOfBoundsException if {@code baseImageIndex} is
* negative or greater than or equal to {@code resolutionVariants}
* length.
*
* @since 9
*/
public BaseMultiResolutionImage(int baseImageIndex,
Image... resolutionVariants) {
if (resolutionVariants == null || resolutionVariants.length == 0) {
throw new IllegalArgumentException(
"Null or zero-length array is passed");
}
if (baseImageIndex < 0 || baseImageIndex >= resolutionVariants.length) {
throw new IndexOutOfBoundsException("Invalid base image index: "
+ baseImageIndex);
}
this.baseImageIndex = baseImageIndex;
this.resolutionVariants = Arrays.copyOf(resolutionVariants,
resolutionVariants.length);
for (Image resolutionVariant : this.resolutionVariants) {
Objects.requireNonNull(resolutionVariant,
"Resolution variant can't be null");
}
}
@Override
public Image getResolutionVariant(double destImageWidth,
double destImageHeight) {
checkSize(destImageWidth, destImageHeight);
for (Image rvImage : resolutionVariants) {
if (destImageWidth <= rvImage.getWidth(null)
&& destImageHeight <= rvImage.getHeight(null)) {
return rvImage;
}
}
return resolutionVariants[resolutionVariants.length - 1];
}
private static void checkSize(double width, double height) {
if (width <= 0 || height <= 0) {
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