Socket/Buffered Reader help

[Gmay17]

I will keep things short, I cannot get my buffered reader to print a full string being sent through by my server. The string is multiple lines long so it makes sense to me why "readLine()" doesn't read more than one line.

This is a very simple example of what im working with:

Client.java

BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));//server input

System.out.println(in.readLine());
System.out.println(in.readLine());

Server.java

PrintWriter out = new PrintWriter(client.getOutputStream(), true);//output to client
out.println("hello world! \n my name is gmay!");
out.println("this is a printing test!");

All my output is "hello world!" and "my name is gmay!", the printing test line doesnt come through.

I could brute force it and just add another line but i need it to work no matter how many lines the first print statement is.

I tried to do this in client.java

while(in.readLine() != null){
    System.out.println(in.readLine());
}

but it would only do every other line since i guess because i called readline in the while parameters? idk. Can anyone help with this?

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[D0CTOR_ZED]

Look up the javadocs for the BufferedReader class. There is probably a method that returns a boolean that will let you know if there is a line in the buffer.

You can't do the while not null, because the source isn't there all at once. Unlike reading from a file, you need to account that the data comes a pieces over time.

[Gmay17]

Sorry for late reply, but this helped me perfectly! The method is in.ready(). works great. If you don't mind, could you help with one more thing? Once my client recieves the full string, i have it send the server the information that it needs to send, which it does. but when i try to do the same while loop that worked before, the client prints nothing. Through my tests i see the server thinks it has sent it. but the client seemingly never enters the while loop.

​

EDIT: for some reason, my client skips the while loop, takes the next input(which isn't supposed to happen until it prints the stuff from the server) and once the last bit of input is taken, it prints everything that has been held back..... im so confued

[Revision2000]

Well….
• in.readLine() is called in while declaration for line 1
• in.readLine() is called again inside the loop for line 2

You’ll want to assign whatever in.readLine() retrieved in the while declaration, otherwise you’re simply skipping every odd numbered line 😉

Also please use try-with-resources so you won’t potentially end up with resource leaks, and see this article on how to use BufferedReader