pragma solidity ^0.4.11;

contract Test {
   uint private val;

   function getVal() constant returns(uint) {
       return val;
   }

   function setVal(uint newVal) payable {
       val = newVal;
   }

   function() {
       val++;
   }
}

contract.getVal.call(function(err, val) {
    //
});

contract.setVal.sendTransaction(newVal,
  {
     gas: gas,
     from: web3.eth.defaultAccount
  },
  function(err, result) {
      //
  });