1. 数组的引用传递
public class TestArray {
public static void changeAry1(int[] ary){
int[] ary1 = {9,9,9};
ary = ary1;
}
public static void changeAry2(int[] ary){
ary[0] = 100;
}
public static void main(String[] args) {
int[] ary = {1,2,3};
System.out.println(Arrays.toString(ary));
changeAry1(ary);
System.out.println(Arrays.toString(ary));
changeAry2(ary);
System.out.println(Arrays.toString(ary));
}
}
2. 对象的引用传递
public class TestObject {
public static void change1(Person p){
p = new TestObject().new Person();
p.age= 100;
p.name = "Lily";
}
public static void change2(Person p){
Person pNew = new TestObject().new Person();
pNew.age= 200;
pNew.name = "Mary";
p = pNew;
}
public static void change3(Person p){
p.age= 200;
p.name = "Tomy";
}
public static void main(String[] args) {
Person p = new TestObject().new Person();
p.age = 50;
p.name="John";
change1(p);
System.out.println(p);
change2(p);
System.out.println(p);
change3(p);
System.out.println(p);
}
class Person{
private int age;
private String name;
public String toString(){
return this.age+","+this.name;
}
}
}
3. 再写一个jdk自带类的引用传递
public class TestOtherObject {
public static void change1(List list){
list = null;
}
public static void change2(List list){
list.add(null);
}
public static void main(String[] args) {
List list = new ArrayList();
change1(list);
System.out.println(list.size());
change2(list);
System.out.println(list.size());
}
}
4. 字符串也是引用类型，也是引用传递
public class TestString {
public static void changeStr1(String str){
String newValue = "changeValue";
str = newValue;
// 或者直接str = "changeValue"; 也是一样
}
public static String changeStr2(String str){
str = "changeValue";
return str;
}public static void main(String[] args) {
String str = "hello";
System.out.println(str);
changeStr1(str);
System.out.println(str);
str = changeStr2(str);
System.out.println(str);
}
}
如何理解java的引用传递
时间： 2024-11-07 15:10:03