fix checkType errors about module hippo4j-threadpool-rpc.

threadpool/rpc/src/main/java/cn/hippo4j/rpc/client/NettyClientConnection.java

@@ -49,6 +49,8 @@ public class NettyClientConnection implements ClientConnection {
      * Obtain the connection timeout period. The default value is 30s
      */
     long timeout = 30000L;
+    final int nanosPerMilliSecond = 1000000;
+
     EventLoopGroup worker = new NioEventLoopGroup();
     NettyConnectPool connectionPool;
     ChannelFuture future;
@@ -74,7 +76,7 @@ public class NettyClientConnection implements ClientConnection {
             }
             // Wait for execution to complete
             ResultHolder.putThread(key, Thread.currentThread());
-            LockSupport.parkNanos(timeout() * 1000000);
+            LockSupport.parkNanos(timeout() * nanosPerMilliSecond);
             response = ResultHolder.get(key);
             if (response == null) {
                 throw new TimeOutException("Timeout waiting for server-side response");

threadpool/rpc/src/main/java/cn/hippo4j/rpc/coder/NettyEncoder.java

@@ -34,7 +34,8 @@ import java.io.Serializable;
  */
 public class NettyEncoder extends MessageToByteEncoder<Serializable> {
 
-    private static final byte[] BYTE = new byte[4];
+    private static final int BYTE_LENGTH = 4;
+    private static final byte[] BYTE = new byte[BYTE_LENGTH];
 
     @Override
     protected void encode(ChannelHandlerContext ctx, Serializable msg, ByteBuf out) throws Exception {
@@ -49,6 +50,6 @@ public class NettyEncoder extends MessageToByteEncoder<Serializable> {
             throw new CoderException("The encoding is abnormal, which may be caused by the transfer object being unable to be serialized");
         }
         int endIndex = out.writerIndex();
-        out.setInt(startIndex, endIndex - startIndex - 4);
+        out.setInt(startIndex, endIndex - startIndex - BYTE_LENGTH);
     }
 }

threadpool/rpc/src/main/java/cn/hippo4j/rpc/handler/HandlerManager.java

@@ -73,6 +73,10 @@ public interface HandlerManager<T> {
         return new HandlerEntity<>(order, handler, name);
     }
 
+    /**
+     * handler entity
+     * @param <T>
+     */
     @Getter
     @AllArgsConstructor
     class HandlerEntity<T> implements Comparable<HandlerEntity<T>> {

threadpool/rpc/src/main/java/cn/hippo4j/rpc/model/DefaultRequest.java

@@ -71,10 +71,12 @@ public final class DefaultRequest implements Request {
 
     @Override
     public boolean equals(Object o) {
-        if (this == o)
+        if (this == o) {
             return true;
-        if (o == null || getClass() != o.getClass())
+        }
+        if (o == null || getClass() != o.getClass()) {
             return false;
+        }
         DefaultRequest that = (DefaultRequest) o;
         return Objects.equals(key, that.key)
                 && Objects.equals(className, that.className)

threadpool/rpc/src/main/java/cn/hippo4j/rpc/model/DefaultResponse.java

@@ -84,10 +84,12 @@ public class DefaultResponse implements Response {
 
     @Override
     public boolean equals(Object o) {
-        if (this == o)
+        if (this == o) {
             return true;
-        if (o == null || getClass() != o.getClass())
+        }
+        if (o == null || getClass() != o.getClass()) {
             return false;
+        }
         DefaultResponse that = (DefaultResponse) o;
         return Objects.equals(key, that.key) && Objects.equals(cls, that.cls);
     }

threadpool/rpc/src/main/java/cn/hippo4j/rpc/server/NettyServerConnection.java

@@ -56,6 +56,7 @@ public class NettyServerConnection extends AbstractNettyHandlerManager implement
     Class<? extends ServerChannel> socketChannelCls = NioServerSocketChannel.class;
     ChannelFuture future;
     Channel channel;
+    private final int maxPortNum = 65535;
 
     public NettyServerConnection(EventLoopGroup leader, EventLoopGroup worker, List<ChannelHandler> handlers) {
         super(handlers);
@@ -80,7 +81,7 @@ public class NettyServerConnection extends AbstractNettyHandlerManager implement
     @Override
     public void bind(ServerPort port) {
         int serverPort = port.getPort();
-        if (serverPort < 0 || serverPort > 65535) {
+        if (serverPort < 0 || serverPort > maxPortNum) {
             throw new ConnectionException("The port number " + serverPort + " is outside 0~65535, which is not a legal port number");
         }
         ServerBootstrap server = new ServerBootstrap();