src/main/java/com/alipay/remoting/rpc/RpcServer.java
public boolean isConnected(String remoteAddr) {
        Url url = this.rpcRemoting.addressParser.parse(remoteAddr);
        return this.isConnected(url);
    }
public boolean isConnected(String remoteAddr) {
        Url url = this.rpcRemoting.addressParser.parse(remoteAddr);
        return this.isConnected(url);
    }
check whether a client address connected

@param remoteAddr
@return