add io demo

src/main/java/io/github/ehlxr/io/BioServer.java

@@ -0,0 +1,95 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright © 2020 xrv <xrg@live.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package io.github.ehlxr.io;
+
+import org.apache.commons.io.IOUtils;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.ServerSocketChannel;
+import java.nio.channels.SocketChannel;
+import java.nio.charset.StandardCharsets;
+
+/**
+ * @author ehlxr
+ * @since 2021-01-23 20:07.
+ */
+public class BioServer {
+    public static void main(String[] args) throws IOException {
+        ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
+
+        // 监听 8080 端口进来的 TCP 链接
+        serverSocketChannel.socket().bind(new InetSocketAddress(8080));
+
+        //noinspection InfiniteLoopStatement
+        while (true) {
+            // 这里会阻塞，直到有一个请求的连接进来
+            SocketChannel socketChannel = serverSocketChannel.accept();
+
+            // 开启一个新的线程来处理这个请求，然后在 while 循环中继续监听 8080 端口
+            SocketHandler handler = new SocketHandler(socketChannel);
+            //noinspection AlibabaAvoidManuallyCreateThread
+            new Thread(handler).start();
+        }
+    }
+
+    static class SocketHandler implements Runnable {
+        private final SocketChannel socketChannel;
+
+        public SocketHandler(SocketChannel socketChannel) {
+            this.socketChannel = socketChannel;
+        }
+
+        @Override
+        public void run() {
+
+            ByteBuffer buffer = ByteBuffer.allocate(1024);
+            try {
+                // 将请求数据读入 Buffer 中
+                int num;
+                while ((num = socketChannel.read(buffer)) > 0) {
+                    // 读取 Buffer 内容之前先 flip 一下
+                    buffer.flip();
+
+                    // 提取 Buffer 中的数据
+                    byte[] bytes = new byte[num];
+                    buffer.get(bytes);
+
+                    String re = new String(bytes, StandardCharsets.UTF_8);
+                    System.out.println("收到请求：" + re);
+
+                    // 回应客户端
+                    ByteBuffer writeBuffer = ByteBuffer.wrap(("我已经收到你的请求，你的请求内容是：" + re).getBytes());
+                    socketChannel.write(writeBuffer);
+
+                    buffer.clear();
+                }
+            } catch (IOException e) {
+                IOUtils.closeQuietly(socketChannel);
+            }
+        }
+    }
+}

src/main/java/io/github/ehlxr/io/Client.java

@@ -0,0 +1,59 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright © 2020 xrv <xrg@live.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package io.github.ehlxr.io;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.SocketChannel;
+import java.nio.charset.StandardCharsets;
+
+/**
+ * @author ehlxr
+ * @since 2021-01-23 20:09.
+ */
+public class Client {
+    public static void main(String[] args) throws IOException {
+        SocketChannel socketChannel = SocketChannel.open();
+        socketChannel.connect(new InetSocketAddress("localhost", 8080));
+
+        // 发送请求
+        ByteBuffer buffer = ByteBuffer.wrap("1234567890".getBytes());
+        socketChannel.write(buffer);
+
+        // 读取响应
+        ByteBuffer readBuffer = ByteBuffer.allocate(1024);
+        int num;
+        if ((num = socketChannel.read(readBuffer)) > 0) {
+            readBuffer.flip();
+
+            byte[] re = new byte[num];
+            readBuffer.get(re);
+
+            String result = new String(re, StandardCharsets.UTF_8);
+            System.out.println("返回值: " + result);
+        }
+    }
+}

src/main/java/io/github/ehlxr/io/SelectorServer.java

@@ -0,0 +1,92 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright © 2020 xrv <xrg@live.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package io.github.ehlxr.io;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.nio.ByteBuffer;
+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;
+
+/**
+ * @author ehlxr
+ * @since 2021-01-23 20:18.
+ */
+public class SelectorServer {
+    public static void main(String[] args) throws IOException {
+        Selector selector = Selector.open();
+
+        ServerSocketChannel server = ServerSocketChannel.open();
+        server.socket().bind(new InetSocketAddress(8080));
+
+        // 将其注册到 Selector 中，监听 OP_ACCEPT 事件
+        server.configureBlocking(false);
+        server.register(selector, SelectionKey.OP_ACCEPT);
+
+        //noinspection InfiniteLoopStatement
+        while (true) {
+            int readyChannels = selector.select();
+            if (readyChannels == 0) {
+                continue;
+            }
+            Set<SelectionKey> readyKeys = selector.selectedKeys();
+            // 遍历
+            Iterator<SelectionKey> iterator = readyKeys.iterator();
+            while (iterator.hasNext()) {
+                SelectionKey key = iterator.next();
+                iterator.remove();
+
+                if (key.isAcceptable()) {
+                    // 有已经接受的新的到服务端的连接
+                    SocketChannel socketChannel = server.accept();
+
+                    // 有新的连接并不代表这个通道就有数据，
+                    // 这里将这个新的 SocketChannel 注册到 Selector，监听 OP_READ 事件，等待数据
+                    socketChannel.configureBlocking(false);
+                    socketChannel.register(selector, SelectionKey.OP_READ);
+                } else if (key.isReadable()) {
+                    // 有数据可读
+                    // 上面一个 if 分支中注册了监听 OP_READ 事件的 SocketChannel
+                    SocketChannel socketChannel = (SocketChannel) key.channel();
+                    ByteBuffer readBuffer = ByteBuffer.allocate(1024);
+                    int num = socketChannel.read(readBuffer);
+                    if (num > 0) {
+                        // 处理进来的数据...
+                        System.out.println("收到数据：" + new String(readBuffer.array()).trim());
+                        ByteBuffer buffer = ByteBuffer.wrap("返回给客户端的数据...".getBytes());
+                        socketChannel.write(buffer);
+                    } else if (num == -1) {
+                        // -1 代表连接已经关闭
+                        socketChannel.close();
+                    }
+                }
+            }
+        }
+    }
+}