小编use*_*039的帖子

请解释一下List- raw type和List<Object>.之间的区别.

以下代码给出了运行时错误:

public static void main(String[] args) {
    List<String> strings = new ArrayList<String>();
    unsafeAdd(strings, new Integer(42));
    String s = strings.get(0); // Compiler-generated cast
}
private static void unsafeAdd(List list, Object o) {
    list.add(o);
}

这给出了编译时错误:

public static void main(String[] args) {
    List<String> strings = new ArrayList<String>();
    unsafeAdd(strings, new Integer(42));
    String s = strings.get(0); // Compiler-generated cast
}
private static void unsafeAdd(List<Object> list, Object o) {
    list.add(o);
}