更新 招聘信息

code/src/main/java/com/raorao/interview/pdd/Friends.java

@@ -4,7 +4,7 @@ import java.util.ArrayList;
 import java.util.Scanner;
 
 /**
- * .
+ * 题目描述： .
  *
  * @author Xiong Raorao
  * @since 2018-08-05-20:03

code/src/main/java/com/raorao/java/io/Main.java

@@ -0,0 +1,11 @@
+package com.raorao.java.io;
+
+/**
+ * .
+ *
+ * @author Xiong Raorao
+ * @since 2018-08-07-9:58
+ */
+public class Main {
+
+}

code/src/main/java/com/raorao/java/io/aio/SimpleClient.java

@@ -0,0 +1,45 @@
+package com.raorao.java.io.aio;
+
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.AsynchronousSocketChannel;
+import java.nio.charset.Charset;
+import java.util.concurrent.ExecutionException;
+
+/**
+ * 异步非阻塞IO (AIO) 的客户端.
+ *
+ * @author Xiong Raorao
+ * @since 2018-08-07-14:38
+ */
+public class SimpleClient {
+
+  public static void main(String[] args) {
+    // 用于读取数据的ByteBuffer。
+    ByteBuffer buff = ByteBuffer.allocate(1024);
+    Charset utf = Charset.forName("utf-8");
+    try (
+        // ①创建AsynchronousSocketChannel对象
+        AsynchronousSocketChannel clientChannel
+            = AsynchronousSocketChannel.open()) {
+      // ②连接远程服务器
+      clientChannel.connect(new InetSocketAddress("127.0.0.1"
+          , 8888)).get();     //④
+      buff.clear();
+      // ③从clientChannel中读取数据
+      clientChannel.read(buff).get();     //⑤
+      buff.flip();
+      // 将buff中内容转换为字符串
+      String content = utf.decode(buff).toString();
+      System.out.println("服务器信息：" + content);
+    } catch (InterruptedException e) {
+      e.printStackTrace();
+    } catch (ExecutionException e) {
+      e.printStackTrace();
+    } catch (IOException e) {
+      e.printStackTrace();
+    }
+  }
+}

code/src/main/java/com/raorao/java/io/aio/SimpleServer.java

@@ -0,0 +1,43 @@
+package com.raorao.java.io.aio;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.AsynchronousServerSocketChannel;
+import java.nio.channels.AsynchronousSocketChannel;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Future;
+
+/**
+ * 使用AIO 实现异步非阻塞通信.
+ *
+ * 步骤：AsynchronousServerSocketChannel用于服务器端，只要三步
+ *
+ * 1.调用open()静态方法创建AsynchronousServerSocketChannel。
+ *
+ * 2.调用AsynchronousServerSocketChannel的bind()方法让它在指定的IP地址，指定端口监听。
+ *
+ * 3.调用AsynchronousServerSocketChannel的accept()方法接受请求。
+ *
+ * @author Xiong Raorao
+ * @since 2018-08-07-14:30
+ */
+public class SimpleServer {
+
+  public static void main(String[] args)
+      throws IOException, ExecutionException, InterruptedException {
+    AsynchronousServerSocketChannel serverChannel = AsynchronousServerSocketChannel.open();
+    serverChannel.bind(new InetSocketAddress("127.0.0.1", 8888));
+    while (true) {
+      // 采用循环接受来自客户端的连接
+      Future<AsynchronousSocketChannel> future
+          = serverChannel.accept();
+      // 获取连接完成后返回的AsynchronousSocketChannel
+      AsynchronousSocketChannel socketChannel = future.get();
+      // 执行输出。
+      socketChannel.write(ByteBuffer.wrap("欢迎你来自AIO的世界！"
+          .getBytes("UTF-8"))).get();
+    }
+
+  }
+}

code/src/main/java/com/raorao/java/io/nio/NIOClient.java

@@ -0,0 +1,53 @@
+package com.raorao.java.io.nio;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.net.Socket;
+
+/**
+ * .
+ *
+ * @author Xiong Raorao
+ * @since 2018-08-07-10:41
+ */
+public class NIOClient {
+
+  public static void main(String[] args) throws IOException {
+//    Socket socket = new Socket("127.0.0.1", 8888);
+//    OutputStream out = socket.getOutputStream();
+//    String s = "hello world";
+//    out.write(s.getBytes());
+//    out.close();
+
+    Thread t1 = new Thread(() -> {
+      try {
+        Socket socket = new Socket("127.0.0.1", 8888);
+        OutputStream out = socket.getOutputStream();
+        Thread.sleep(2000);
+        String s = "hello world, this is thread-1, I have slept 2s";
+        out.write(s.getBytes());
+        out.close();
+      } catch (IOException e) {
+        e.printStackTrace();
+      } catch (InterruptedException e) {
+        e.printStackTrace();
+      }
+    });
+    Thread t2 = new Thread(() -> {
+      try {
+        Socket socket = new Socket("127.0.0.1", 8888);
+        OutputStream out = socket.getOutputStream();
+        Thread.sleep(3000);
+        String s = "hello world, this is thread-2, I have slept 3s";
+        out.write(s.getBytes());
+        out.close();
+      } catch (IOException e) {
+        e.printStackTrace();
+      } catch (InterruptedException e) {
+        e.printStackTrace();
+      }
+    });
+    t2.start();
+    t1.start();
+  }
+}

code/src/main/java/com/raorao/java/io/nio/NIOMain.java

@@ -0,0 +1,103 @@
+package com.raorao.java.io.nio;
+
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.net.ServerSocket;
+import java.nio.ByteBuffer;
+import java.nio.channels.FileChannel;
+import java.nio.channels.SelectionKey;
+import java.nio.channels.Selector;
+import java.nio.channels.ServerSocketChannel;
+import java.nio.channels.SocketChannel;
+import java.util.Iterator;
+import java.util.Set;
+
+/**
+ * NIO 应用类.
+ *
+ * @author Xiong Raorao
+ * @since 2018-08-07-10:02
+ */
+public class NIOMain {
+
+  public static void main(String[] args) throws IOException {
+    //fastCopy("E:\\test.mkv", "D:\\test.mkv");
+    selector();
+  }
+
+  public static void fastCopy(String src, String dst) throws IOException {
+    FileInputStream fin = new FileInputStream(src);      /* 获取源文件的输入字节流 */
+    FileChannel fcin = fin.getChannel();                 /* 获取输入字节流的文件通道 */
+    FileOutputStream fout = new FileOutputStream(dst);  /* 获取目标文件的输出字节流 */
+    FileChannel fcout = fout.getChannel();               /* 获取输出字节流的通道 */
+    ByteBuffer buffer = ByteBuffer.allocateDirect(1024); /* 为缓冲区分配 1024 个字节 */
+    while (true) {
+      int r = fcin.read(buffer);                       /* 从输入通道中读取数据到缓冲区中 */
+      if (r == -1) {                                   /* read() 返回 -1 表示 EOF */
+        break;
+      }
+      buffer.flip();                                   /* 切换读写 */
+      fcout.write(buffer);                             /* 把缓冲区的内容写入输出文件中 */
+      buffer.clear();                                  /* 清空缓冲区 */
+    }
+  }
+
+  /**
+   * nio 选择器的使用方法。只有套接字的Channel 才能被配置为非阻塞，FileChannel 不行，这里采用SocketChannel 来测试。
+   */
+  public static void selector() throws IOException {
+    Selector selector = Selector.open();
+    ServerSocketChannel ssChannel = ServerSocketChannel.open();
+    ssChannel.configureBlocking(false); // 配置非阻塞
+    ssChannel.register(selector, SelectionKey.OP_ACCEPT); // 注册选择器
+
+    ServerSocket serverSocket = ssChannel.socket();
+    InetSocketAddress address = new InetSocketAddress("127.0.0.1", 8888);
+    serverSocket.bind(address);
+
+    while (true) {
+      selector.select();
+      Set<SelectionKey> keys = selector.selectedKeys();
+      Iterator<SelectionKey> keyIterator = keys.iterator();
+      while (keyIterator.hasNext()) {
+        SelectionKey key = keyIterator.next();
+        if (key.isAcceptable()) {
+          ServerSocketChannel ssChannel1 = (ServerSocketChannel) key.channel();
+          // 服务器会为每个新连接创建一个 SocketChannel
+          SocketChannel sChannel = ssChannel1.accept();
+          sChannel.configureBlocking(false);
+          // 这个新连接主要用于从客户端读取数据
+          sChannel.register(selector, SelectionKey.OP_READ);
+        } else if (key.isReadable()) {
+          SocketChannel sChannel = (SocketChannel) key.channel();
+          System.out.println(readDataFromSocketChannel(sChannel));
+          sChannel.close();
+        }
+        keyIterator.remove();
+      }
+    }
+  }
+
+  private static String readDataFromSocketChannel(SocketChannel sChannel) throws IOException {
+    ByteBuffer buffer = ByteBuffer.allocate(1024);
+    StringBuilder data = new StringBuilder();
+    while (true) {
+      buffer.clear();
+      int n = sChannel.read(buffer);
+      if (n == -1) {
+        break;
+      }
+      buffer.flip();
+      int limit = buffer.limit();// 这个地方limit表示的是缓冲区有数据部分实际的末尾部分，小于等于缓冲区容量1024.
+      char[] dst = new char[limit];
+      for (int i = 0; i < limit; i++) {
+        dst[i] = (char) buffer.get(i);
+      }
+      data.append(dst);
+      buffer.clear();
+    }
+    return data.toString();
+  }
+}

code/src/main/java/com/raorao/leetcode/Q1.java

@@ -0,0 +1,52 @@
+package com.raorao.leetcode;
+
+/**
+ * 二叉树最短路径.
+ *
+ * 题目描述：Given a binary tree, find its minimum depth.The minimum depth is the number of nodes along
+ * the shortest path from the root node down to the nearest leaf node.
+ *
+ * @author Xiong Raorao
+ * @since 2018-08-07-17:01
+ */
+public class Q1 {
+
+
+  public static void main(String[] args) {
+
+  }
+
+  /**
+   思路：
+   递归，若为空树返回0；
+   若左子树为空，则返回右子树的最小深度+1；（加1是因为要加上根这一层，下同）
+   若右子树为空，则返回左子树的最小深度+1；
+   若左右子树均不为空，则取左、右子树最小深度的较小值，+1；
+   * @param root
+   * @return
+   */
+  public int run(TreeNode root) {
+    if (root == null) {
+      return 0;
+    }
+
+    if (root.left == null) {
+      return run(root.right) + 1;
+    }
+    if (root.right == null) {
+      return run(root.left) + 1;
+    }
+    return run(root.left) < run(root.right) ? run(root.left) + 1 : run(root.right) + 1;
+  }
+
+  static class TreeNode {
+
+    int val;
+    TreeNode left;
+    TreeNode right;
+
+    TreeNode(int x) {
+      val = x;
+    }
+  }
+}