Reference for Processing version 1.1+. If you have a previous version, use the reference included with your software. If you see any errors or have suggestions, »please let us know. If you prefer a more technical reference, visit the »Processing Javadoc.



Client myClient; 
int dataIn; 
void setup() { 
  size(200, 200); 
  // Connect to the local machine at port 5204.
  // This example will not run if you haven't
  // previously started a server on this port
  myClient = new Client(this, "", 5204); 
void draw() { 
  if (myClient.available() > 0) { 
    dataIn =; 
Description A client connects to a server and sends data back and forth. If anything goes wrong with the connection, for example the host is not there or is listening on a different port, an exception is thrown.
available() Returns the number of bytes in the buffer waiting to be read
read() Returns a value from the buffer
readChar() Returns the next byte in the buffer as a char
readBytes() Reads everything in the buffer
readBytesUntil() Reads from the buffer of bytes up to and including a particular character
readString() Returns the buffer as a String
readStringUntil() Returns the buffer as a String up to and including a particular character
write() Writes bytes, chars, ints, bytes[], Strings
clear() Clears the buffer
stop() Disconnects from the server
ip() Returns the IP address of the machine as a String
Client(parent, host, port)
Client(parent, socket)
parent PApplet: typically use "this"
host String: address of the server
port int: port to read/write from on the server
socket Socket:
Usage Application
Updated on June 14, 2010 12:05:29pm EDT

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