[Demonstration 1]

[Buggy Method]
public static void main(String[] args) throws Exception {
    Schedule example = exampleSchedule();
    Runtime.getRuntime().addShutdownHook(new Thread() {

        @Override
        public void run() {
            System.out.println(example.movesTried + " moves tried");
            System.out.println(example.history.size() + " moves in history");
            example.print();
        }
    });
    if (example.fillSchedule(null)) {
        System.out.println("success!");
        example.print();
    } else {
        System.out.println("failed.");
    }
    example.errors.clear();
    example.errors.strict = false;
    example.validate();
    // this should not print anything in case of success
    example.errors.print();
}

[Buggy Hunk]
example.validate();

[Patch]
example.validate(null);

[Demonstration 2]

[Buggy Method]
public BufferedImage create(int w, int h) {
    return new BufferedImage(h, h, type);
}

[Buggy Hunk]
return new BufferedImage( h, h, type );

[Patch]
return new BufferedImage( w, h, type );