美滋滋

标记这个类，看完了

dubbo-remoting/dubbo-remoting-api/src/main/java/com/alibaba/dubbo/remoting/buffer/ByteBufferBackedChannelBuffer.java

@@ -22,28 +22,43 @@ import java.io.InputStream;
 import java.io.OutputStream;
 import java.nio.ByteBuffer;
 
+/**
+ * 基于 ByteBuffer 的 ChannelBuffer 实现类
+ */
 public class ByteBufferBackedChannelBuffer extends AbstractChannelBuffer {
 
+    /**
+     * buffer
+     * java.nio.ByteBuffer
+     */
     private final ByteBuffer buffer;
-
+    /**
+     * 容量
+     */
     private final int capacity;
 
     public ByteBufferBackedChannelBuffer(ByteBuffer buffer) {
         if (buffer == null) {
             throw new NullPointerException("buffer");
         }
-
+        // buffer
         this.buffer = buffer.slice();
+        // 容量
         capacity = buffer.remaining();
+        // 设置 `writerIndex`
         writerIndex(capacity);
     }
 
     public ByteBufferBackedChannelBuffer(ByteBufferBackedChannelBuffer buffer) {
+        // buffer
         this.buffer = buffer.buffer;
+        // 容量
         capacity = buffer.capacity;
+        // 设置 `writerIndex` `readerIndex`
         setIndex(buffer.readerIndex(), buffer.writerIndex());
     }
 
+    @Override
     public ChannelBufferFactory factory() {
         if (buffer.isDirect()) {
             return DirectChannelBufferFactory.getInstance();
@@ -52,12 +67,12 @@ public class ByteBufferBackedChannelBuffer extends AbstractChannelBuffer {
         }
     }
 
-
+    @Override
     public int capacity() {
         return capacity;
     }
 
-
+    @Override
     public ChannelBuffer copy(int index, int length) {
         ByteBuffer src;
         try {
@@ -74,12 +89,12 @@ public class ByteBufferBackedChannelBuffer extends AbstractChannelBuffer {
         return new ByteBufferBackedChannelBuffer(dst);
     }
 
-
+    @Override
     public byte getByte(int index) {
         return buffer.get(index);
     }
 
-
+    @Override
     public void getBytes(int index, byte[] dst, int dstIndex, int length) {
         ByteBuffer data = buffer.duplicate();
         try {
@@ -90,7 +105,7 @@ public class ByteBufferBackedChannelBuffer extends AbstractChannelBuffer {
         data.get(dst, dstIndex, length);
     }
 
-
+    @Override
     public void getBytes(int index, ByteBuffer dst) {
         ByteBuffer data = buffer.duplicate();
         int bytesToCopy = Math.min(capacity() - index, dst.remaining());
@@ -102,7 +117,7 @@ public class ByteBufferBackedChannelBuffer extends AbstractChannelBuffer {
         dst.put(data);
     }
 
-
+    @Override
     public void getBytes(int index, ChannelBuffer dst, int dstIndex, int length) {
         if (dst instanceof ByteBufferBackedChannelBuffer) {
             ByteBufferBackedChannelBuffer bbdst = (ByteBufferBackedChannelBuffer) dst;
@@ -118,6 +133,7 @@ public class ByteBufferBackedChannelBuffer extends AbstractChannelBuffer {
     }
 
 
+    @Override
     public void getBytes(int index, OutputStream out, int length) throws IOException {
         if (length == 0) {
             return;
@@ -135,31 +151,31 @@ public class ByteBufferBackedChannelBuffer extends AbstractChannelBuffer {
         }
     }
 
-
+    @Override
     public boolean isDirect() {
         return buffer.isDirect();
     }
 
-
+    @Override
     public void setByte(int index, int value) {
         buffer.put(index, (byte) value);
     }
 
-
+    @Override
     public void setBytes(int index, byte[] src, int srcIndex, int length) {
         ByteBuffer data = buffer.duplicate();
         data.limit(index + length).position(index);
         data.put(src, srcIndex, length);
     }
 
-
+    @Override
     public void setBytes(int index, ByteBuffer src) {
         ByteBuffer data = buffer.duplicate();
         data.limit(index + src.remaining()).position(index);
         data.put(src);
     }
 
-
+    @Override
     public void setBytes(int index, ChannelBuffer src, int srcIndex, int length) {
         if (src instanceof ByteBufferBackedChannelBuffer) {
             ByteBufferBackedChannelBuffer bbsrc = (ByteBufferBackedChannelBuffer) src;
@@ -174,7 +190,7 @@ public class ByteBufferBackedChannelBuffer extends AbstractChannelBuffer {
         }
     }
 
-
+    @Override
     public ByteBuffer toByteBuffer(int index, int length) {
         if (index == 0 && length == capacity()) {
             return buffer.duplicate();
@@ -184,7 +200,7 @@ public class ByteBufferBackedChannelBuffer extends AbstractChannelBuffer {
         }
     }
 
-
+    @Override
     public int setBytes(int index, InputStream in, int length) throws IOException {
         int readBytes = 0;
 
@@ -224,18 +240,19 @@ public class ByteBufferBackedChannelBuffer extends AbstractChannelBuffer {
         return readBytes;
     }
 
-
+    @Override
     public byte[] array() {
         return buffer.array();
     }
 
-
+    @Override
     public boolean hasArray() {
         return buffer.hasArray();
     }
 
-
+    @Override
     public int arrayOffset() {
         return buffer.arrayOffset();
     }
+
 }

dubbo-remoting/dubbo-remoting-api/src/main/java/com/alibaba/dubbo/remoting/buffer/HeapChannelBuffer.java

@@ -25,10 +25,14 @@ import java.nio.channels.ClosedChannelException;
 import java.nio.channels.GatheringByteChannel;
 import java.nio.channels.ScatteringByteChannel;
 
+/**
+ * 基于字节数组的 Buffer 实现类
+ */
 public class HeapChannelBuffer extends AbstractChannelBuffer {
 
     /**
      * The underlying heap byte array that this buffer is wrapping.
+     * 字节数组
      */
     protected final byte[] array;
 
@@ -65,30 +69,42 @@ public class HeapChannelBuffer extends AbstractChannelBuffer {
         setIndex(readerIndex, writerIndex);
     }
 
+    @Override
+    public ChannelBufferFactory factory() {
+        return HeapChannelBufferFactory.getInstance();
+    }
+
+    @Override
     public boolean isDirect() {
         return false;
     }
 
+    @Override
     public int capacity() {
         return array.length;
     }
 
+    @Override
     public boolean hasArray() {
         return true;
     }
 
+    @Override
     public byte[] array() {
         return array;
     }
 
+    @Override
     public int arrayOffset() {
         return 0;
     }
 
+    @Override
     public byte getByte(int index) {
         return array[index];
     }
 
+    @Override
     public void getBytes(int index, ChannelBuffer dst, int dstIndex, int length) {
         if (dst instanceof HeapChannelBuffer) {
             getBytes(index, ((HeapChannelBuffer) dst).array, dstIndex, length);
@@ -97,14 +113,17 @@ public class HeapChannelBuffer extends AbstractChannelBuffer {
         }
     }
 
+    @Override
     public void getBytes(int index, byte[] dst, int dstIndex, int length) {
         System.arraycopy(array, index, dst, dstIndex, length);
     }
 
+    @Override
     public void getBytes(int index, ByteBuffer dst) {
         dst.put(array, index, Math.min(capacity() - index, dst.remaining()));
     }
 
+    @Override
     public void getBytes(int index, OutputStream out, int length)
             throws IOException {
         out.write(array, index, length);
@@ -115,26 +134,31 @@ public class HeapChannelBuffer extends AbstractChannelBuffer {
         return out.write(ByteBuffer.wrap(array, index, length));
     }
 
+    @Override
     public void setByte(int index, int value) {
         array[index] = (byte) value;
     }
 
+    @Override
     public void setBytes(int index, ChannelBuffer src, int srcIndex, int length) {
-        if (src instanceof HeapChannelBuffer) {
+        if (src instanceof HeapChannelBuffer) { // 都是 HeapChannelBuffer ，可以直接 System#arraycopy(...)
             setBytes(index, ((HeapChannelBuffer) src).array, srcIndex, length);
         } else {
             src.getBytes(srcIndex, array, index, length);
         }
     }
 
+    @Override
     public void setBytes(int index, byte[] src, int srcIndex, int length) {
         System.arraycopy(src, srcIndex, array, index, length);
     }
 
+    @Override
     public void setBytes(int index, ByteBuffer src) {
         src.get(array, index, src.remaining());
     }
 
+    @Override
     public int setBytes(int index, InputStream in, int length) throws IOException {
         int readBytes = 0;
         do {
@@ -180,6 +204,7 @@ public class HeapChannelBuffer extends AbstractChannelBuffer {
         return readBytes;
     }
 
+    @Override
     public ChannelBuffer copy(int index, int length) {
         if (index < 0 || length < 0 || index + length > array.length) {
             throw new IndexOutOfBoundsException();
@@ -190,10 +215,7 @@ public class HeapChannelBuffer extends AbstractChannelBuffer {
         return new HeapChannelBuffer(copiedArray);
     }
 
-    public ChannelBufferFactory factory() {
-        return HeapChannelBufferFactory.getInstance();
-    }
-
+    @Override
     public ByteBuffer toByteBuffer(int index, int length) {
         return ByteBuffer.wrap(array, index, length);
     }