From 0f9933df8ea71eef969f1e19792cbf5f53d4da75 Mon Sep 17 00:00:00 2001
From: zhuyanshuo <3663541984@qq.com>
Date: Wed, 29 Apr 2026 12:40:53 +0800
Subject: [PATCH] Pair

---
 w8/Pair.java         | 38 ++++++++++++++++++++++++++++++++++++++
 w8/TestPairSwap.java | 17 +++++++++++++++++
 2 files changed, 55 insertions(+)
 create mode 100644 w8/Pair.java
 create mode 100644 w8/TestPairSwap.java

diff --git a/w8/Pair.java b/w8/Pair.java
new file mode 100644
index 0000000..7bc0814
--- /dev/null
+++ b/w8/Pair.java
@@ -0,0 +1,38 @@
+public class Pair<K, V> {
+    private K key;
+    private V value;
+
+    // 构造方法
+    public Pair(K key, V value) {
+        this.key = key;
+        this.value = value;
+    }
+
+    // Getter/Setter
+    public K getKey() {
+        return key;
+    }
+
+    public void setKey(K key) {
+        this.key = key;
+    }
+
+    public V getValue() {
+        return value;
+    }
+
+    public void setValue(V value) {
+        this.value = value;
+    }
+
+    // ✅ 修复后的静态 swap 方法
+    public static <K, V> Pair<V, K> swap(Pair<K, V> pair) {
+        return new Pair<>(pair.getValue(), pair.getKey());
+    }
+
+    // 重写 toString
+    @Override
+    public String toString() {
+        return "Pair{" + "key=" + key + ", value=" + value + '}';
+    }
+}
\ No newline at end of file
diff --git a/w8/TestPairSwap.java b/w8/TestPairSwap.java
new file mode 100644
index 0000000..969828a
--- /dev/null
+++ b/w8/TestPairSwap.java
@@ -0,0 +1,17 @@
+public class TestPairSwap {
+    public static void main(String[] args) {
+        // 1. 原始 Pair：String + Integer（姓名-年龄）
+        Pair<String, Integer> person = new Pair<>("张三", 20);
+        System.out.println("交换前：" + person);
+
+        // 2. 调用静态 swap 方法，得到交换后的 Pair
+        Pair<Integer, String> swappedPerson = Pair.swap(person);
+        System.out.println("交换后：" + swappedPerson);
+
+        // 3. 相同类型的 Pair 也可以正常使用
+        Pair<Double, Double> point = new Pair<>(116.40, 39.90);
+        System.out.println("交换前坐标：" + point);
+        Pair<Double, Double> swappedPoint = Pair.swap(point);
+        System.out.println("交换后坐标：" + swappedPoint);
+    }
+}
\ No newline at end of file