java如何正确比较从数据报数据包接收的字符串值？

Question

我正在制作一个简单的客户机-服务器程序。当客户端发送字符串“start”时，我希望服务器开始执行一些代码。现在，我让客户端发送一个带有消息“start”的数据报数据包，服务器从数据包中获取字节缓冲区，将其转换为字符串，然后将该字符串值与字符串文本“start”进行比较。显然我做错了什么，因为我的代码从未进入if(sentence.equals(start){ System.out.println("ok");}的for循环

我的代码：

public static void main(String args[]) throws IOException{


    byte[] receiveData;
    byte[] sendData;
    DatagramSocket serverSocket = new DatagramSocket(2014);


    while(true){

        receiveData = new byte[15];
        DatagramPacket frame = new DatagramPacket(receiveData, receiveData.length);
        serverSocket.receive(frame);
        InetAddress IPaddress = frame.getAddress();
        System.out.println("INET " + IPaddress);


        byte[] data;

        int port = frame.getPort();
        System.out.println("port " + port);

        String sentence = new String(frame.getData());
        String start =  new String("start");


        System.out.println("RECEIVED FROM CLIENT: " + sentence);


        if(sentence.equals(start)){
            System.out.println("ok");
        }
    }
}

Answer 1

进行以下更改

    String sentence = new String(frame.getData(), 0, frame.getLength());