Sending files over network

[TerraViper-5]

Hello. I have made a simple server in java that sends requested files to clients via http://<ip>/<filename>. It creates a new thread for each client. The problem is the speed is limited to 100kBps per thread. I searched a little bit and I think I know the problem:

FileInputStream input = null;  
DataOutputStream output = null;
...
output = new DataOutputStream(client.getOutputStream()); //client = Socket
...
input = new FileInputStream(requestedFile);
...
int read;
        try {
            for(;;) {
                read = input.read();
                if (read==-1) {
                    break;
                }
                output.write(read);
            }
        }
...
client.close();

I think the problem is because I write byte by byte and that is slow, I think I should use BufferedReader and Writer. And heres the problem: I dont know how to add those two. I tried a few things but I cant make it work. FileWriter just cant use client.getOutputStream() as parameter. Please, some help here. thanks.