maven之pom.xml依赖

<dependency>
    <groupId>net.coobird</groupId>
    <artifactId>thumbnailator</artifactId>
    <version>0.4.8</version>
</dependency>

直接贴代码：

import net.coobird.thumbnailator.Thumbnails;

import java.io.IOException;

/**
 * Created by Liuxd on 2018/08/21.
 */
public class Test {


    public static void main(String[] args) {
//      Thumbnails.of(file.getInputStream()).scale(1.00f).outputQuality(0.25f).toOutputStream(outputStream);
        try {
            //保持纵横比，质量降低为原来的42%
            Thumbnails.of("E:/PICTURE/1.jpg").scale(1.00f).outputQuality(0.42f).toFile("E:/PICTURE/4.jpg");
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
}