形参和实参的区别

Author: enjoyCoding666

src/main/java/com/base/Swap.java

@@ -0,0 +1,43 @@
+package com.base;
+
+public class Swap {
+        public static void main(String[] args) {
+            int x = 5;
+            int y = 10;
+            swap(x,y);
+            System.out.println("使用swap1()交换：");
+            System.out.println(x);
+            System.out.println(y);
+
+            Value v = new Value(5,10);
+            swap(v);
+            System.out.println("使用swap()2交换：");
+            System.out.println(v.x);
+            System.out.println(v.y);
+        }
+
+        // 无效的交换：形参的改变无法反作用于实参
+        public static void swap(int x,int y) {
+            int temp = x;
+            x = y;
+            y = temp;
+        }
+
+        // 有效的交换：通过引用（变量指向一个对象）来修改成员变量
+        public static void swap(Value value) {
+            int temp = value.x;
+            value.x = value.y;
+            value.y = temp;
+        }
+    }
+
+    class Value{
+        int x;
+        int y;
+
+        public Value(int x,int y) {
+            this.x = x;
+            this.y = y;
+        }
+    }
+