Java 9 Multi-Resolution Image API
Java 9 New FeaturesJava 9 defines the multi-resolution image API, allowing developers to easily manipulate and display images of different resolutions.
The following are the main operation methods of multi-resolution images:
Image getResolutionVariant(double destImageWidth, double destImageHeight)− Get an image variant at a specific resolution - represents a logical image of a specific size with a known resolution in DPI, and this image is the best variant.
List<Image> getResolutionVariants()− Return a readable list of resolution image variants.
Examples
import java.io.IOException;
import java.net.URL;
import java.net.MalformedURLException;
import java.util.ArrayList;
import java.util.List;
import java.awt.Image;
import java.awt.image.MultiResolutionImage;
import java.awt.image.BaseMultiResolutionImage;
import javax.imageio.ImageIO;
public class Tester {
public static void main(String[] args) throws IOException, MalformedURLException {
List<String> imgUrls = List.of("http://www.example.com/wp-content/themes/example/assets/img/[email protected]",
"http://www.example.com/wp-content/themes/example/assets/img/example-logo.png",
"http://www.example.com/wp-content/themes/example/assets/images/qrcode.png");
List<Image> images = new ArrayList<Image>();
for (String url : imgUrls) {
images.add(ImageIO.read(new URL(url)));
}
//Read all images
MultiResolutionImage multiResolutionImage =
new BaseMultiResolutionImage(images.toArray(new Image[0]));
//Get all resolutions of an image
List<Image> variants = multiResolutionImage.getResolutionVariants();
System.out.println("Total number of images: " + variants.size());
for (Image img : variants) {
System.out.println(img);
}
//Get the corresponding image resolution based on different sizes
Image variant1 = multiResolutionImage.getResolutionVariant(156, 45);
System.out.printf("\nImage for destination[%d,%d]: [%d,%d]",
156, 45, variant1.getWidth(null), variant1.getHeight(null));
Image variant2 = multiResolutionImage.getResolutionVariant(311, 89);
System.out.printf("\nImage for destination[%d,%d]: [%d,%d]", 311, 89,
variant2.getWidth(null), variant2.getHeight(null));
Image variant3 = multiResolutionImage.getResolutionVariant(622, 178);
System.out.printf("\nImage for destination[%d,%d]: [%d,%d]", 622, 178,
variant3.getWidth(null), variant3.getHeight(null));
Image variant4 = multiResolutionImage.getResolutionVariant(300, 300);
System.out.printf("\nImage for destination[%d,%d]: [%d,%d]", 300, 300,
variant4.getWidth(null), variant4.getHeight(null));
}
}