class a{
...
public void changeit(String wanttobechanged) {
wanttobechanged = "new value"; //not right
}public void change(StringBuffer itok) {
itok.append ("ok !"); // itok's content changed
}
...
}
...
public void changeit(String wanttobechanged) {
wanttobechanged = "new value"; //not right
}public void change(StringBuffer itok) {
itok.append ("ok !"); // itok's content changed
}
...
}
是指..生成一个新的String对象,c指向新的String对象...
c 原本指向myString,后来经过c="my String has been changed";之后,c原本指向的地址上的内容还是“myString”,但是c现在指向了另一个地址,那个地址里的内容是“my string has been changed.”