JARにリソースを持たせる例

ButtonTest.java

import javax.swing.JFrame;
import javax.swing.JButton;
import javax.swing.ImageIcon;

class ButtonTest extends JFrame {
    public static void main(String[] args) {
        new ButtonTest().setVisible(true);
    }

    ButtonTest() {
        setSize(200, 100);
        setDefaultCloseOperation(EXIT_ON_CLOSE);

        ImageIcon icon = new ImageIcon(
            getClass().getResource("onebit_11.png"));
        JButton button = new JButton("Save", icon);
        getContentPane().add(button);
    }
}

Makefile

TARGET = ButtonTest.jar

$(TARGET): ButtonTest.class onebit_11.png
	jar 0cvfe $@ ButtonTest $^

ButtonTest.class: ButtonTest.java
	javac $<

clean:
	rm -f $(TARGET) *.class

# onebit_11.png is in the public domain.
# http://www.icojam.com/blog/?p=177