http server (examplehub#184)

realDuYuanChao · web-flow · commit c571e02ab15e · 2021-09-23T08:06:15.000+08:00
diff --git a/src/main/java/com/examplehub/basics/network/HttpServerExample.java b/src/main/java/com/examplehub/basics/network/HttpServerExample.java
@@ -0,0 +1,76 @@
+package com.examplehub.basics.network;
+
+import java.io.*;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.nio.charset.StandardCharsets;
+
+public class HttpServerExample {
+  public static void main(String[] args) throws IOException {
+    ServerSocket ss = new ServerSocket(8080);
+    System.out.println("server is running...");
+    for (;;) {
+      Socket sock = ss.accept();
+      System.out.println("connected from " + sock.getRemoteSocketAddress());
+      new Handler(sock).start();
+    }
+  }
+}
+class Handler extends Thread {
+  Socket sock;
+
+  public Handler(Socket sock) {
+    this.sock = sock;
+  }
+
+  public void run() {
+    try (InputStream input = this.sock.getInputStream()) {
+      try (OutputStream output = this.sock.getOutputStream()) {
+        handle(input, output);
+      }
+    } catch (Exception e) {
+      try {
+        this.sock.close();
+      } catch (IOException ioe) {
+      }
+      System.out.println("client disconnected.");
+    }
+  }
+
+  private void handle(InputStream input, OutputStream output) throws IOException {
+    var reader = new BufferedReader(new InputStreamReader(input, StandardCharsets.UTF_8));
+    var writer = new BufferedWriter(new OutputStreamWriter(output, StandardCharsets.UTF_8));
+    // TODO: 处理HTTP请求
+    // 读取HTTP请求:
+    boolean requestOk = false;
+    String first = reader.readLine();
+    if (first.startsWith("GET / HTTP/1.")) {
+      requestOk = true;
+    }
+    for (;;) {
+      String header = reader.readLine();
+      if (header.isEmpty()) { // 读取到空行时, HTTP Header读取完毕
+        break;
+      }
+      System.out.println(header);
+    }
+    System.out.println(requestOk ? "Response OK" : "Response Error");
+    if (!requestOk) {
+      // 发送错误响应:
+      writer.write("HTTP/1.0 404 Not Found\r\n");
+      writer.write("Content-Length: 0\r\n");
+      writer.write("\r\n");
+    } else {
+      // 发送成功响应:
+      String data = "<html><body><h1>Hello, world!</h1></body></html>";
+      int length = data.getBytes(StandardCharsets.UTF_8).length;
+      writer.write("HTTP/1.0 200 OK\r\n");
+      writer.write("Connection: close\r\n");
+      writer.write("Content-Type: text/html\r\n");
+      writer.write("Content-Length: " + length + "\r\n");
+      writer.write("\r\n"); // 空行标识Header和Body的分隔
+      writer.write(data);
+    }
+    writer.flush();
+  }
+}
