code: public void matchSet(Hashtable elements, int combine_op, int compare_op) throws DBException
      {
          // Delete the old search filter
          m_filter = null;
          // If combine_op is not a logical operator, throw an exception
          if ((combine_op & LOGICAL_OPER_MASK) == 0)
          {
              throw new DBException();
              // If compare_op is not a binary operator, throw an exception
          }
          if ((compare_op & BINARY_OPER_MASK) == 0)
          {
              throw new DBException();
              // Create a vector that will hold the comparison nodes for all elements in the hashtable
          }
          Vector compareVector = new Vector();
          // For each of the elements in the hashtable, create a comparison node for the match
          for (Enumeration e = elements.keys(); e.hasMoreElements();)
          {
              // Get the element name from the enumerator
              // and its value
              String elementName = (String) e.nextElement();
              String elementValue = (String) elements.get(elementName);
              // Create a comparison node for this list and store it as the filter
              SearchBaseLeafComparison comparenode = new SearchBaseLeafComparison(elementName,
                      compare_op, elementValue);
              // Add this leaf node to the vector
              compareVector.addElement(comparenode);
          }
          // Now return a node that holds this set of leaf nodes
          m_filter = new SearchBaseNode(combine_op, compareVector);
      }
docs: Change the search filter to one that specifies a set of elements and their values
  that must match, and the operator to use to combine the elements.
  Each key is compared for an equal match to the value, and all
  comparisons are combined by the specified logical operator (OR or AND).
  The old search filter is deleted.
  
  @param elements is a hashtable holding key-value pairs
  @param combine_op is the logical operator to be used to combine the comparisons
  @param compare_op is the binary operator to be used for the comparisons
  @exception DBException