1 files changed, 162 insertions, 0 deletions
diff --git a/simple/simple-http/src/main/java/org/simpleframework/http/socket/service/FrameConsumer.java b/simple/simple-http/src/main/java/org/simpleframework/http/socket/service/FrameConsumer.java
new file mode 100644
index 0000000..579d6ef
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+++ b/simple/simple-http/src/main/java/org/simpleframework/http/socket/service/FrameConsumer.java
@@ -0,0 +1,162 @@
+/*
+ * FrameConsumer.java February 2014
+ *
+ * Copyright (C) 2014, Niall Gallagher <niallg@users.sf.net>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or 
+ * implied. See the License for the specific language governing 
+ * permissions and limitations under the License.
+ */
+
+package org.simpleframework.http.socket.service;
+
+import java.io.IOException;
+
+import org.simpleframework.http.socket.Frame;
+import org.simpleframework.http.socket.FrameType;
+import org.simpleframework.transport.ByteCursor;
+
+/**
+ * The <code>FrameConsumer</code> object is used to read a WebSocket
+ * frame as defined by RFC 6455. This is a state machine that can read
+ * the data one byte at a time until the entire frame has been consumed.
+ * 
+ * @author Niall Gallagher
+ * 
+ * @see org.simpleframework.http.socket.service.FrameCollector
+ */
+class FrameConsumer {
+   
+   /**
+    * This is used to consume the header part of the frame.
+    */
+   private FrameHeaderConsumer header;
+   
+   /**
+    * This is used to interpret the header and create a frame.
+    */
+   private FrameBuilder builder;
+   
+   /**
+    * This is used to buffer the bytes that form the frame.
+    */
+   private byte[] buffer;
+   
+   /**
+    * This is a count of the payload bytes currently consumed.
+    */
+   private int count;
+
+   /**
+    * Constructor for the <code>FrameConsumer</code> object. This is
+    * used to create a consumer to read the bytes that form the frame 
+    * from an underlying TCP connection. Internally a buffer is created
+    * to allow bytes to be consumed and collected in chunks.
+    */
+   public FrameConsumer() {
+      this.header = new FrameHeaderConsumer();
+      this.builder = new FrameBuilder(header);
+      this.buffer = new byte[2048];
+   }
+   
+   /**
+    * This is used to determine the type of frame. Interpretation of
+    * this type is outlined in RFC 6455 and can be loosely categorised
+    * as control frames and either data or binary frames.     
+    * 
+    * @return this returns the type of frame that this represents
+    */
+   public FrameType getType() {
+      return header.getType();
+   }
+
+   /**
+    * This is used to create a frame object to represent the data that
+    * has been consumed. The frame created will make a copy of the 
+    * internal byte buffer so this method should be used sparingly.
+    * 
+    * @return this returns a frame created from the consumed bytes
+    */
+   public Frame getFrame() {    
+      return builder.create(buffer, count);
+   }
+
+   /**
+    * This consumes frame bytes using the provided cursor. The consumer
+    * acts as a state machine by consuming the data as that data 
+    * becomes available, this allows it to consume data asynchronously
+    * and dispatch once the whole frame has been consumed.
+    * 
+    * @param cursor the cursor to consume the frame data from
+    */
+   public void consume(ByteCursor cursor) throws IOException {
+      while (cursor.isReady()) {
+         if(!header.isFinished()) {
+            header.consume(cursor);
+         }
+         if(header.isFinished()) {            
+            int length = header.getLength();
+            
+            if(count <= length) {            
+               if(buffer.length < length) {
+                  buffer = new byte[length];
+               }
+               if(count < length) {
+                  int size = cursor.read(buffer, count, length - count);
+                  
+                  if(size == -1) {
+                     throw new IOException("Could only read " + count + " of length " + length);
+                  }
+                  count += size;
+               }
+               if(count == length) {
+                  if(header.isMasked()) {
+                     byte[] mask = header.getMask();
+                     
+                     for (int i = 0; i < count; i++) {               
+                        buffer[i] ^= mask[i % 4];
+                     }                     
+                  }   
+                  break;
+               }
+            }
+         }
+      }
+   }
+
+   /**
+    * This is used to determine if the collector has finished. If it
+    * is not finished the collector will be registered to listen for
+    * an I/O interrupt to read further bytes of the frame.
+    * 
+    * @return true if the collector has finished consuming
+    */
+   public boolean isFinished() {
+      if(header.isFinished()) {
+         int length = header.getLength();
+         
+         if(count == length) {
+            return true;
+         }
+      }
+      return false;
+   }
+   
+   /**
+    * This resets the collector to its original state so that it can 
+    * be reused. Reusing the collector has obvious benefits as it will
+    * reduce the amount of memory churn for the server.  
+    */   
+   public void clear() {
+      header.clear();
+      count = 0;
+   }
+}