first commit

io-study-master/io-study/src/main/java/netty/upload/codec/UploadFileDecodecer.java

@@ -0,0 +1,59 @@
+package netty.upload.codec;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.ByteToMessageDecoder;
+import netty.upload.FileDto;
+
+import java.util.List;
+
+/**
+ * @description:
+ * @author: lld
+ * @version: 1.0
+ */
+public class UploadFileDecodecer extends ByteToMessageDecoder {
+
+
+    //请求上传
+    //创建文件
+    //将客户端数据写入本地磁盘
+    //command 4  fileName 4 8
+    //数据长度 + 数据
+    @Override
+    protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws Exception {
+        if(in.readableBytes() < 8){
+            return;
+        }
+        //command 4
+        int command = in.readInt();
+
+        FileDto fileDto = new FileDto();
+
+        int fileNameLen = in.readInt();
+
+        if(in.readableBytes() < fileNameLen){
+            in.resetReaderIndex();
+            return;
+        }
+        
+        byte[] data = new byte[fileNameLen];
+        in.readBytes(data);
+        String fileName = new String(data);
+        fileDto.setCommand(command);
+        fileDto.setFileName(fileName);
+
+        if(command == 2){
+            int dataLen = in.readInt();
+            if(in.readableBytes() < dataLen){
+                in.resetReaderIndex();
+                return;
+            }
+            byte[] fileData = new byte[dataLen];
+            in.readBytes(fileData);
+            fileDto.setBytes(fileData);
+        }
+        in.markReaderIndex();//10004
+        out.add(fileDto);
+    }
+}