Tomcat Architecture系列掌握TOMCAT连接器

<code class="java">public interface Connector {
  // 核心连接器方法
  public void setService(Service service);
  public Service getService();
  public void init() throws LifecycleException;
  public void start() throws LifecycleException;
  public void stop() throws LifecycleException;

  // 协议配置
  public void setProtocol(String protocol);
  public String getProtocol();

  // 端口配置
  public void setPort(int port);
  public int getPort();
}</code>

<code class="java">public class ConnectorPipeline {
  private final List<Valve> valves = new ArrayList<>();
  private Valve basic = null;

  public void addValve(Valve valve) {
    valves.add(valve);
  }

  public void invoke(Request request, Response response) {
    // 通过阀门链处理
    for (Valve valve : valves) {
      valve.invoke(request, response);
    }
    // 最后调用基本阀门
    if (basic != null) {
      basic.invoke(request, response);
    }
  }
}</code>

<code class="java">public class Http11Protocol extends AbstractHttp11Protocol<NioChannel> {

  @Override
  protected void initializeConnectionLatch() {
    // 初始化连接计数
    connectionLatch = new CountDownLatch(1);
  }

  @Override
  protected Processor createProcessor() {
    // 创建HTTP处理器
    Http11Processor processor = new Http11Processor(
      getMaxHttpHeaderSize(),
      getEndpoint(),
      getMaxTrailerSize(),
      allowedTrailerHeaders,
      getMaxExtensionSize(),
      getMaxSwallowSize(),
      getHttp11Protocol().getRelaxedPathChars(),
      getHttp11Protocol().getRelaxedQueryChars());
    processor.setAdapter(getAdapter());
    return processor;
  }
}</code>

<code class="java">public class Http11Processor implements ActionHook, Processor {

  @Override
  public SocketState process(SocketWrapperBase<NioChannel> socketWrapper)
    throws IOException {
    // 初始化请求和响应
    Request req = new Request();
    Response res = new Response();

    // 解析HTTP请求
    parseRequest(socketWrapper, req);

    // 处理请求
    getAdapter().service(req, res);

    // 发送响应
    sendResponse(res);

    return SocketState.CLOSED;
  }
}</code>

<code class="java">public class AjpProtocol extends AbstractAjpProtocol<NioChannel> {

  @Override
  protected Processor createProcessor() {
    AjpProcessor processor = new AjpProcessor(getPacketSize(), getEndpoint());
    processor.setAdapter(getAdapter());
    return processor;
  }

  @Override
  protected void initializeConnectionLatch() {
    connectionLatch = new CountDownLatch(1);
  }
}</code>

<code class="java">public class AjpMessage {
    private final byte[] buf;
    private int pos;

    public void reset() {
        pos = 0;
    }

    public void appendByte(int val) {
        buf[pos++] = (byte) val;
    }

    public void appendInt(int val) {
        buf[pos++] = (byte) ((val >>> 8) & 0xff);
        buf[pos++] = (byte) (val & 0xff);
    }
}</code>

<code class="java">public class NioEndpoint extends AbstractJsseEndpoint<NioChannel> {

    private Poller[] pollers;
    private NioSelectorPool selectorPool;

    @Override
    protected void startInternal() throws Exception {
        // 初始化NIO组件
        if (!running) {
            running = true;
            paused = false;

            // 创建工作线程集合
            processorCache = new SynchronizedStack<>(
                    SynchronizedStack.DEFAULT_SIZE,
                    socketProperties.getProcessorCache());

            // 启动Poller线程
            pollers = new Poller[getPollerThreadCount()];
            for (int i = 0; i < pollers.length; i++) {
                pollers[i] = new Poller();
                pollers[i].start();
            }
        }
    }
}</code>

<code class="java">public class NioChannel implements ByteChannel {
  private final SocketChannel sc;
  private final NioEndpoint endpoint;

  @Override
  public int read(ByteBuffer dst) throws IOException {
    return sc.read(dst);
  }

  @Override
  public int write(ByteBuffer src) throws IOException {
    return sc.write(src);
  }
}</code>

<code class="java">public class ConnectorOptimizer {
  public void optimizeBuffers(Connector connector) {
    // 设置最佳缓冲区大小
    connector.setProperty("socketBuffer", "65536");
    connector.setProperty("maxHttpHeaderSize", "8192");
    connector.setProperty("maxPostSize", "2097152");
  }
}</code>

<code class="java">public class ConnectorTroubleshooter {
    public void diagnoseConnector(Connector connector) {
        // 检查连接状态
        if (!connector.getState().isAvailable()) {
            // 检查端口可用性
            if (!isPortAvailable(connector.getPort())) {
                throw new ConnectorException("端口 " + connector.getPort() + " 正在使用");
            }

            // 检查线程池
            if (connector.getProperty("maxThreads") == null) {
                logger.warn("线程池配置不正确");
            }
        }
    }
}</code>

<code class="java">public class ConnectorMonitor {
    private final JmxConnectorStats stats;

    public void monitorConnector() {
        // 监控活动连接
        int activeConnections = stats.getActiveConnections();

        // 监控请求处理时间
        long processingTime = stats.getProcessingTime();

        // 监控线程池使用情况
        int activeThreads = stats.getCurrentThreadCount();
        int maxThreads = stats.getMaxThreads();

        // 超过阈值时记录日志或发出警报
        if (activeConnections > threshold) {
            logger.warn("活动连接过多: " + activeConnections);
        }
    }
}</code>