Location-Aware Web Service Composition Based on the Mixture Rank of Web Services and Web Service Requests

Algorithm 3

Schsoft (abstract service s_m).

// GLLB

1. Calculate the weight of different QoS according to formulas in Sections 5.1 and 5.2;

2. Calculate the aggregation value for the service candidate and service request of the abstract

 service s_m;

3. ;

4. ;

  //sort SCO in descending order;

  //tp can be a service candidate (=“candidate”) or a service request (=“request”);

  //ID indicates the one for the service candidate or the service request;

  //Val indicates the value of aggregation function for the service candidate or the service

request;

5. Select service composition request sr that cannot find a service candidate in Algorithm 2

  (Algorithm 2)

6. Get the left position lp and the right position rp;

7. minlost=+, selectr=-1;

8. For

   If service candidate can satisfy sr for all the QoS

    minlostemp=;

    If minlosttemp< minlost

     minlost=minlosttemp;

     selectr=;

    Endif

   EndIf

 Endfor

9. If selectr=-1

   Assign selectr to sr;

 EndIf

  //minmore records the total value of the QoS of the web service that is more than the

requirement of the web service request under the condition that all of the hard requirements of

the service request have been satisfied.

10. ;

  //search from the position of the end of the right position;

11. While ()

   11.1 If can satisfy the hard requirement of QoS of

      selectr=;

      Assign selectr to ;

      Break;

    EndIf

  EndWhile