Java内容重新整理删除过期的东西

Java/JavaDemo/codedemo/reactor/Reader.java

@@ -0,0 +1,94 @@
+package cn.aofeng.demo.reactor;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.Selector;
+import java.nio.channels.SocketChannel;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+/**
+ * 负责读取客户端的请求数据并解析。
+ * 
+ * @author <a href="mailto:aofengblog@163.com">NieYong </a>
+ */
+public class Reader {
+
+    private final static Logger _logger = Logger.getLogger(Reader.class.getName());
+    
+    private SocketChannel _clientChannel;
+    
+    private Decoder _decoder;
+    
+    private final static int BUFFER_SIZE = 512;
+    
+    private ByteBuffer _buffer = ByteBuffer.allocate(BUFFER_SIZE);
+    
+    public Reader(Selector selector, SocketChannel clientChannel) {
+        this._clientChannel = clientChannel;
+    }
+    
+    public void setDecoder(Decoder decoder) {
+        this._decoder = decoder;
+    }
+    
+    public void read() throws IOException {
+        int readCount = _clientChannel.read(_buffer);
+        if (-1 == readCount) {
+            _clientChannel.close();
+        }
+        
+        _buffer.flip();
+        int oldLimit = _buffer.limit();
+        String line = null;
+        while( (line = (String) _decoder.decode(_buffer)) != null ) { // 处理一次多行发送过来的情况
+            if (_logger.isLoggable(Level.FINE)) {
+                _logger.fine("收到的数据："+line);
+            }
+            
+            // 处理业务逻辑
+            ProcessService service= new ProcessService(_clientChannel, line);
+            String result = service.execute();
+            
+            // 发送响应
+            Writer writer = new Writer(_clientChannel, result);
+            writer.setEncoder(new LineEncoder());
+            writer.write();
+            
+            // 重建临时数据缓冲区
+            rebuildBuffer(line.length());
+        }
+        
+        // 缓冲区数据还没有符合一个decode数据的条件，重置数据缓冲区的状态方便append数据
+        if (oldLimit  == _buffer.limit()) {
+            resetBuffer();
+        }
+    }
+    
+    private void resetBuffer() {
+        _buffer.position(_buffer.limit());
+        _buffer.limit(_buffer.capacity());
+    }
+
+    /**
+     * 重建临时数据缓冲区。
+     * 
+     * @param lineSize 收到的一行数据（不包括行结束符）的长度 
+     */
+    private void rebuildBuffer(int lineSize) {
+        if (_buffer.limit() == lineSize) {
+            // 数据刚好是一行
+            _buffer = ByteBuffer.allocate(BUFFER_SIZE);
+        } else if (_buffer.limit() > lineSize) {
+            // 数据多于一行
+            byte[] temp = new byte[_buffer.limit() - lineSize];
+            System.arraycopy(_buffer.array(), lineSize, temp, 0, temp.length);
+            _buffer = ByteBuffer.allocate(BUFFER_SIZE);
+            _buffer.put(temp);
+            _buffer.flip();
+        } else {
+            // nothing
+        }
+    }
+
+}