[Feature] java的闭包，用内部类实现

miniyk2012 · miniyk2012 · commit 15c478b2877b · 2017-09-03T21:01:34.000+08:00
diff --git a/students/812350401/src/main/java/com/coderising/myknowledgepoint/closure/Milk.java b/students/812350401/src/main/java/com/coderising/myknowledgepoint/closure/Milk.java
@@ -0,0 +1,49 @@
+package com.coderising.myknowledgepoint.closure;
+
+/**
+ * Created by thomas_young on 27/8/2017.
+ */
+public class Milk {
+
+    public final static String name = "纯牛奶";//名称
+
+    private static int num = 16;//数量
+
+    public Milk()
+    {
+        System.out.println(name+"：16/每箱");
+    }
+
+    /**
+     * 闭包
+     * @return 返回一个喝牛奶的动作
+     */
+    public Active HaveMeals()
+    {
+        return () -> {
+                if(num == 0)
+                {
+                    System.out.println("木有了，都被你丫喝完了.");
+                    return;
+                }
+                num--;
+                System.out.println("喝掉一瓶牛奶");
+            };
+    }
+
+    /**
+     * 获取剩余数量
+     */
+    public void currentNum()
+    {
+        System.out.println(name+"剩余："+num);
+    }
+}
+
+/**
+ * 通用接口
+ */
+interface Active
+{
+    void drink();
+}
diff --git a/students/812350401/src/main/java/com/coderising/myknowledgepoint/closure/Person.java b/students/812350401/src/main/java/com/coderising/myknowledgepoint/closure/Person.java
@@ -0,0 +1,41 @@
+package com.coderising.myknowledgepoint.closure;
+
+/**
+ * Created by thomas_young on 27/8/2017.
+ */
+public class Person {
+
+    public static void main(String[] args) {
+        //买一箱牛奶
+        Milk m = new Milk();
+
+        Active haveMeals = m.HaveMeals();
+
+        //没事喝一瓶
+        haveMeals.drink();
+        //有事喝一瓶
+        haveMeals.drink();
+
+        //看看还剩多少？
+        m.currentNum();
+        m = null;
+        haveMeals.drink();  // 闭包会导致资源不被回收
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+        haveMeals.drink();
+    }
+
+}
