Concatenation of php class static variables

My first class:

<?php
  require_once( 'error/DisconnectedHandler.php' );
  require_once( 'error/NoSuchRequestHandler.php' );

  class NetworkManager {

  public static final $RESPONSE_JUMP = 1000;
  ....

My second class:

<?php
    require_once( '../NetworkManager.php' );

    class DisconnectedHandler implements Handler{
        public static $TYPE          = 2000;
        public static $RESPONSE_TYPE = self::$TYPE + NetworkManager::$RESPONSE_JUMP;
        public static $VER           = 0;

I get an error in this line:

public static $RESPONSE_TYPE = self::$TYPE + NetworkManager::$RESPONSE_JUMP;

Eclipse IDE paint $TYPE in red and says:

Multiple annotations f开发者_StackOverflowound at this line:
- syntax error, unexpected '$TYPE', expecting 
 'identifier'
- syntax error, unexpected '$TYPE', expecting 
 'identifier'

What is the correct syntax for that?

---

Static variable declarations (as well as class constants) must be literally defined and cannot contain expression as they are evaluated prior to runtime.

You have to initialize your DisconnectedHandler::$RESPONE_TYPE in a constructor or more likely in a static initializer method.