初次提交：泛型类Java代码

kv.java

@@ -0,0 +1,31 @@
+package w8;
+
+public class Pair<K, V> {
+    private K key;
+    private V value;
+
+    public Pair(K key, V value) {
+        this.key = key;
+        this.value = value;
+    }
+
+    public Pair<V, K> swap() {
+        return new Pair<>(this.value, this.key);
+    }
+
+    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;
+    }
+}

kv1.java

@@ -0,0 +1,32 @@
+package w8;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class Cache<K, V> {
+    private final Map<K, V> cacheMap;
+
+    public Cache() {
+        cacheMap = new HashMap<>();
+    }
+
+    public void put(K key, V value) {
+        cacheMap.put(key, value);
+    }
+
+    public V get(K key) {
+        return cacheMap.get(key);
+    }
+
+    public void remove(K key) {
+        cacheMap.remove(key);
+    }
+
+    public void clear() {
+        cacheMap.clear();
+    }
+
+    public int size() {
+        return cacheMap.size();
+    }
+}