方法startsWith subString

Question

我无法解决这个问题，这似乎是微不足道但却无法抓住它......

public static void handleClient(){

System.out.println("Opening PORT...");
Socket link = null;

try{

link =servSock.accept();
Scanner input = new Scanner(link.getInputStream());
PrintWriter output = new PrintWriter(link.getOutputStream(),true);


String message = input.nextLine();
String username = null;
if (message.startstWith("username"))

{
    username = message.subString(7);
    output.println("Your username is: "+ username);
    System.out.println(username+" is connecting...");

    message = input.nextLine();

    while (!message.equals("*END*"))
        {
        System.out.println(username +" Says: "+message);
        output.println("we received your message..");
        }



}else{

output.println("PLEASE VERIFY hostname...");

}

我收到来自套接字流的内容并将其另存为String

String message = input.nextLine（）;

这是我编译时的结果

    C:\Users\==\Desktop\anoterTest>javac TCPServer.java
TCPServer.java:51: error: cannot find symbol
    if (message.startstWith("username"))
               ^
symbol:   method startstWith(String)
location: variable message of type String
TCPServer.java:54: error: cannot find symbol
            username = message.subString(0,8);
                              ^
symbol:   method subString(int,int)
location: variable message of type String
2 errors

C:\Users\==\Desktop\anoterTest>

Answer 1

startstWith应为startsWith（拼写错误）

和

subString应为substring

Java方法区分大小写

Answer 2

您拼错startsWith startstWith。您还错误substring subString - 大写问题。

Answer 3

String.startsWith

 if (message.startsWith("username"))

而不是

if (message.startstWith("username"))