diff --git a/pom.xml b/pom.xml
index 8d394d4..7d31938 100644
--- a/pom.xml
+++ b/pom.xml
@@ -10,6 +10,9 @@
 
     <properties>
         <netty-all.version>4.1.6.Final</netty-all.version>
+        <lombok.version>1.16.12</lombok.version>
+        <fastjson.version>1.2.29</fastjson.version>
+        <junit.version>4.12</junit.version>
     </properties>
 
     <dependencies>
@@ -18,6 +21,25 @@
             <artifactId>netty-all</artifactId>
             <version>${netty-all.version}</version>
         </dependency>
+
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>${lombok.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>com.alibaba</groupId>
+            <artifactId>fastjson</artifactId>
+            <version>${fastjson.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>${junit.version}</version>
+        </dependency>
+
     </dependencies>
 
     <build>
diff --git a/src/main/java/the/flash/protocol/command/Command.java b/src/main/java/the/flash/protocol/command/Command.java
new file mode 100644
index 0000000..31b3d26
--- /dev/null
+++ b/src/main/java/the/flash/protocol/command/Command.java
@@ -0,0 +1,6 @@
+package the.flash.protocol.command;
+
+public interface Command {
+
+    Byte LOGIN_REQUEST = 1;
+}
diff --git a/src/main/java/the/flash/protocol/command/LoginRequestPacket.java b/src/main/java/the/flash/protocol/command/LoginRequestPacket.java
new file mode 100644
index 0000000..d24753b
--- /dev/null
+++ b/src/main/java/the/flash/protocol/command/LoginRequestPacket.java
@@ -0,0 +1,19 @@
+package the.flash.protocol.command;
+
+import lombok.Data;
+
+import static the.flash.protocol.command.Command.LOGIN_REQUEST;
+
+@Data
+public class LoginRequestPacket extends Packet {
+    private Integer userId;
+
+    private String username;
+
+    private String password;
+
+    @Override
+    public Byte getCommand() {
+        return LOGIN_REQUEST;
+    }
+}
diff --git a/src/main/java/the/flash/protocol/command/Packet.java b/src/main/java/the/flash/protocol/command/Packet.java
new file mode 100644
index 0000000..c4a5945
--- /dev/null
+++ b/src/main/java/the/flash/protocol/command/Packet.java
@@ -0,0 +1,17 @@
+package the.flash.protocol.command;
+
+import com.alibaba.fastjson.annotation.JSONField;
+import lombok.Data;
+
+@Data
+public abstract class Packet {
+    /**
+     * 协议版本
+     */
+    @JSONField(deserialize = false, serialize = false)
+    private Byte version = 1;
+
+
+    @JSONField(serialize = false)
+    public abstract Byte getCommand();
+}
diff --git a/src/main/java/the/flash/protocol/command/PacketCodeC.java b/src/main/java/the/flash/protocol/command/PacketCodeC.java
new file mode 100644
index 0000000..d70f787
--- /dev/null
+++ b/src/main/java/the/flash/protocol/command/PacketCodeC.java
@@ -0,0 +1,85 @@
+package the.flash.protocol.command;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.ByteBufAllocator;
+import the.flash.serialize.Serializer;
+import the.flash.serialize.impl.JSONSerializer;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import static the.flash.protocol.command.Command.LOGIN_REQUEST;
+
+public class PacketCodeC {
+
+    private static final int MAGIC_NUMBER = 0x1234;
+    private static final Map<Byte, Class<? extends Packet>> packetTypeMap;
+    private static final Map<Byte, Serializer> serializerMap;
+
+    static {
+        packetTypeMap = new HashMap<>();
+        packetTypeMap.put(LOGIN_REQUEST, LoginRequestPacket.class);
+
+        serializerMap = new HashMap<>();
+        Serializer serializer = new JSONSerializer();
+        serializerMap.put(serializer.getSerializerAlogrithm(), serializer);
+    }
+
+
+    public ByteBuf encode(Packet packet) {
+        // 1. 创建 ByteBuf 对象
+        ByteBuf byteBuf = ByteBufAllocator.DEFAULT.ioBuffer();
+        // 2. 序列化 java 对象
+        byte[] bytes = Serializer.DEFAULT.serialize(packet);
+
+        // 3. 实际编码过程
+        byteBuf.writeInt(MAGIC_NUMBER);
+        byteBuf.writeByte(packet.getVersion());
+        byteBuf.writeByte(Serializer.DEFAULT.getSerializerAlogrithm());
+        byteBuf.writeByte(packet.getCommand());
+        byteBuf.writeInt(bytes.length);
+        byteBuf.writeBytes(bytes);
+
+        return byteBuf;
+    }
+
+
+    public Packet decode(ByteBuf byteBuf) {
+        // 跳过 magic number
+        byteBuf.skipBytes(4);
+
+        // 跳过版本号
+        byteBuf.skipBytes(1);
+
+        // 序列化算法
+        byte serializeAlgorithm = byteBuf.readByte();
+
+        // 指令
+        byte command = byteBuf.readByte();
+
+        // 数据包长度
+        int length = byteBuf.readInt();
+
+        byte[] bytes = new byte[length];
+        byteBuf.readBytes(bytes);
+
+        Class<? extends Packet> requestType = getRequestType(command);
+        Serializer serializer = getSerializer(serializeAlgorithm);
+
+        if (requestType != null && serializer != null) {
+            return serializer.deserialize(requestType, bytes);
+        }
+
+        return null;
+    }
+
+    private Serializer getSerializer(byte serializeAlgorithm) {
+
+        return serializerMap.get(serializeAlgorithm);
+    }
+
+    private Class<? extends Packet> getRequestType(byte command) {
+
+        return packetTypeMap.get(command);
+    }
+}
diff --git a/src/main/java/the/flash/serialize/Serializer.java b/src/main/java/the/flash/serialize/Serializer.java
new file mode 100644
index 0000000..6abe22b
--- /dev/null
+++ b/src/main/java/the/flash/serialize/Serializer.java
@@ -0,0 +1,25 @@
+package the.flash.serialize;
+
+import the.flash.serialize.impl.JSONSerializer;
+
+public interface Serializer {
+
+    Serializer DEFAULT = new JSONSerializer();
+
+    /**
+     * 序列化算法
+     * @return
+     */
+    byte getSerializerAlogrithm();
+
+    /**
+     * java 对象转换成二进制
+     */
+    byte[] serialize(Object object);
+
+    /**
+     * 二进制转换成 java 对象
+     */
+    <T> T deserialize(Class<T> clazz, byte[] bytes);
+
+}
diff --git a/src/main/java/the/flash/serialize/SerializerAlogrithm.java b/src/main/java/the/flash/serialize/SerializerAlogrithm.java
new file mode 100644
index 0000000..0108ead
--- /dev/null
+++ b/src/main/java/the/flash/serialize/SerializerAlogrithm.java
@@ -0,0 +1,8 @@
+package the.flash.serialize;
+
+public interface SerializerAlogrithm {
+    /**
+     * json 序列化
+     */
+    byte JSON = 1;
+}
diff --git a/src/main/java/the/flash/serialize/impl/JSONSerializer.java b/src/main/java/the/flash/serialize/impl/JSONSerializer.java
new file mode 100644
index 0000000..251f141
--- /dev/null
+++ b/src/main/java/the/flash/serialize/impl/JSONSerializer.java
@@ -0,0 +1,25 @@
+package the.flash.serialize.impl;
+
+import com.alibaba.fastjson.JSON;
+import the.flash.serialize.Serializer;
+import the.flash.serialize.SerializerAlogrithm;
+
+public class JSONSerializer implements Serializer {
+
+    @Override
+    public byte getSerializerAlogrithm() {
+        return SerializerAlogrithm.JSON;
+    }
+
+    @Override
+    public byte[] serialize(Object object) {
+
+        return JSON.toJSONBytes(object);
+    }
+
+    @Override
+    public <T> T deserialize(Class<T> clazz, byte[] bytes) {
+
+        return JSON.parseObject(bytes, clazz);
+    }
+}
diff --git a/src/test/java/the/flash/protocol/command/PacketCodeCTest.java b/src/test/java/the/flash/protocol/command/PacketCodeCTest.java
new file mode 100644
index 0000000..8e51cbd
--- /dev/null
+++ b/src/test/java/the/flash/protocol/command/PacketCodeCTest.java
@@ -0,0 +1,28 @@
+package the.flash.protocol.command;
+
+import io.netty.buffer.ByteBuf;
+import org.junit.Assert;
+import org.junit.Test;
+import the.flash.serialize.Serializer;
+import the.flash.serialize.impl.JSONSerializer;
+
+public class PacketCodeCTest {
+    @Test
+    public void encode() {
+
+        Serializer serializer = new JSONSerializer();
+        LoginRequestPacket loginRequestPacket = new LoginRequestPacket();
+
+        loginRequestPacket.setVersion(((byte) 1));
+        loginRequestPacket.setUserId(123);
+        loginRequestPacket.setUsername("zhangsan");
+        loginRequestPacket.setPassword("password");
+
+        PacketCodeC packetCodeC = new PacketCodeC();
+        ByteBuf byteBuf = packetCodeC.encode(loginRequestPacket);
+        Packet decodedPacket = packetCodeC.decode(byteBuf);
+
+        Assert.assertArrayEquals(serializer.serialize(loginRequestPacket), serializer.serialize(decodedPacket));
+
+    }
+}