add > 队列 链表实现

lihengming · lihengming · commit b3dfb8bcbc3b · 2017-06-23T11:29:42.000+08:00
diff --git a/data-structure-algorithm/src/main/java/data/structure/queue/QueueLinkedImpl.java b/data-structure-algorithm/src/main/java/data/structure/queue/QueueLinkedImpl.java
@@ -0,0 +1,37 @@
+package data.structure.queue;
+
+/**
+ * Created by 李恒名 on 2017/6/23.
+ * <p>
+ * 保存指向首尾节点的指针，每次从链表尾插入，从链表头删除。
+ */
+public class QueueLinkedImpl implements Queue {
+    private Node first, last;
+
+    private class Node {
+        private Node next;
+        private Object element;
+    }
+
+    @Override
+    public void enQueue(Object element) {
+        Node oldLast = last;
+        last = new Node();
+        last.element = element;
+        last.next = null;
+        if (first == null) {
+            first = last;
+        } else {
+            oldLast.element = last;
+        }
+
+    }
+
+    @Override
+    public Object deQueue() {
+        Object element = first.element;
+        first = first.next;
+        if (first == null) last = null;
+        return element;
+    }
+}
diff --git a/data-structure-algorithm/src/main/java/data/structure/queue/Tester.java b/data-structure-algorithm/src/main/java/data/structure/queue/Tester.java
@@ -0,0 +1,24 @@
+package data.structure.queue;
+
+import org.junit.Test;
+
+/**
+ * Created by 李恒名 on 2017/6/8.
+ */
+public class Tester {
+
+
+    //测试队列的链表实现
+    @Test
+    public void test2(){
+        Queue queue = new QueueLinkedImpl();
+
+        queue.enQueue("1");
+        queue.enQueue("2");
+        queue.enQueue("3");
+
+        System.out.println(queue.deQueue());
+        System.out.println(queue.deQueue());
+        System.out.println(queue.deQueue());
+    }
+}
