1    var obj1={"id" : 1, "name" : "java"},
2    obj2={"id" : 1, "name" : "java4you", "gender" : "male"};
3
4    function compare(obj1, obj2) {
5      let obj = {};
6      for(let k in obj1) {
7         if(obj1[k] !== obj2[k]) {
8           obj = Object.assign({}, obj1, obj1[k] = obj2[k]);
9         }
10         
11      }
12      return obj;
13    }