test/jdk/javax/swing/border/TransparentTitleTest.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/*
 * @test
 * @bug 4154572
 * @summary Tests that the area behind a TitledBorder's title string is transparent,
 * allowing the component's background to show through
 * @library /java/awt/regtesthelpers
 * @build PassFailJFrame
 * @run main/manual TransparentTitleTest
 */

import java.awt.GridLayout;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Color;
import java.awt.image.BufferedImage;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.TitledBorder;
import javax.swing.border.LineBorder;

public class TransparentTitleTest {
    private static final String INSTRUCTIONS = """
            If all panels are correctly painted such that the title of the
            border allows the underlying panel image (green rectangle)
            to show through the background of the text,
            then this test passes; else it fails.
            """;

    public static void main(String[] args) throws Exception {
        PassFailJFrame.builder()
                .title("TransparentTitleTest Instructions")
                .instructions(INSTRUCTIONS)
                .columns(40)
                .testUI(TransparentTitleTest::createTestUI)
                .build()
                .awaitAndCheck();
    }

    private static JFrame createTestUI() {
        JFrame frame = new JFrame("TransparentTitleTest");

        frame.setLayout(new GridLayout(3, 6, 5, 5));

        frame.add(new ImagePanel(TitledBorder.TOP, TitledBorder.LEFT));
        frame.add(new ImagePanel(TitledBorder.TOP, TitledBorder.CENTER));
        frame.add(new ImagePanel(TitledBorder.TOP, TitledBorder.RIGHT));
        frame.add(new ImagePanel(TitledBorder.ABOVE_TOP, TitledBorder.LEFT));
        frame.add(new ImagePanel(TitledBorder.ABOVE_TOP, TitledBorder.CENTER));
        frame.add(new ImagePanel(TitledBorder.ABOVE_TOP, TitledBorder.RIGHT));
        frame.add(new ImagePanel(TitledBorder.BELOW_TOP, TitledBorder.LEFT));
        frame.add(new ImagePanel(TitledBorder.BELOW_TOP, TitledBorder.CENTER));
        frame.add(new ImagePanel(TitledBorder.BELOW_TOP, TitledBorder.RIGHT));
        frame.add(new ImagePanel(TitledBorder.BOTTOM, TitledBorder.LEFT));
        frame.add(new ImagePanel(TitledBorder.BOTTOM, TitledBorder.CENTER));
        frame.add(new ImagePanel(TitledBorder.BOTTOM, TitledBorder.RIGHT));
        frame.add(new ImagePanel(TitledBorder.ABOVE_BOTTOM, TitledBorder.LEFT));
        frame.add(new ImagePanel(TitledBorder.ABOVE_BOTTOM, TitledBorder.CENTER));
        frame.add(new ImagePanel(TitledBorder.ABOVE_BOTTOM, TitledBorder.RIGHT));
        frame.add(new ImagePanel(TitledBorder.BELOW_BOTTOM, TitledBorder.LEFT));
        frame.add(new ImagePanel(TitledBorder.BELOW_BOTTOM, TitledBorder.CENTER));
        frame.add(new ImagePanel(TitledBorder.BELOW_BOTTOM, TitledBorder.RIGHT));

        frame.pack();
        return frame;
    }
}

class ImagePanel extends JPanel {

    private final ImageIcon imageIcon;

    private static final BufferedImage bufferedImage =
            new BufferedImage(128, 128, BufferedImage.TYPE_INT_ARGB);

    static {
        Graphics g = bufferedImage.getGraphics();
        g.setColor(Color.GREEN);
        g.fillRect(0, 0, 128, 128);
    }

    public ImagePanel(int titlePos, int titleJust) {
        imageIcon = new ImageIcon(bufferedImage);

        TitledBorder b = new TitledBorder(new LineBorder(Color.black,3), "title text");
        b.setTitlePosition(titlePos);
        b.setTitleJustification(titleJust);
        b.setTitleColor(Color.black);
        setBorder(b);
    }

    public Dimension getPreferredSize() {
        return new Dimension(imageIcon.getIconWidth(), imageIcon.getIconHeight());
    }

    public void paintComponent(Graphics g) {
        imageIcon.paintIcon(this, g, 0, 0);
    }
}