private static void doParam() {
List<String> list = new ArrayList<String>();
list.add("123");
listNull(list);
System.out.println(list.toString());
listAdd(list);
System.out.println(list.toString());
int p = 0;
intAdd(p);
System.out.println(p);
}
public static void intAdd(int p) {
p = 10;
}
public static void listNull(List<String> list) {
list = null;
}
public static void listAdd(List<String> list) {
list.add("aaaa");
}
结果
[123]
[123, aaaa]
0