Пример

protected void finalize() throws Throwable {
System.out.println("Not calling super.finalize()"); //$NON-NLS-1$
}

public static void main( String[] args ) {
SuperFinalize_Example sf = new SuperFinalize_Example();
sf = null;
Runtime.getRuntime().gc();
}

Решение

Добавьте вызов super.finalize() в качестве последнего оператора метода finalize().

protected void finalize() throws Throwable {
try {
System.out.println("Calling super.finalize()"); //$NON-NLS-1$
} finally {
super .finalize();
}
}

public static void main( String[] args ) {
SuperFinalize_Example sf = new SuperFinalize_Example();
sf = null;
Runtime.getRuntime().gc();
}