Test Image

import java.awt.Color;
import java.awt.GradientPaint;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;

public class TestImageIo {

    public static void main(String[] args) {
        TestImageIo testImageIo = new TestImageIo();
        BufferedImage img = testImageIo.imageCreate(600, 600);
        testImageIo.save3(img);
    }

    public BufferedImage imageCreate(int width, int height) {
        BufferedImage img = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
        Graphics2D g2 = img.createGraphics();
        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);;
        int x2 = width / 10;
        int y2 = height / 10;
        GradientPaint gPaint = new GradientPaint(0, 0, Color.RED, x2, y2, Color.BLUE, true);
        g2.setPaint(gPaint);
        g2.fillOval(5, 5, width - 10, height - 10);
        g2.dispose();
        return img;
    }

    public void save3(BufferedImage img) {
        File out = new File("hello.png");
        try {
            ImageIO.write(img, "png", out);
        } catch (IOException e2) {
            System.out.println(e2);
        }
    }
}