Class ActivationClassBuilder

  • All Implemented Interfaces:
    ExpressionClassBuilderInterface

    class ActivationClassBuilder
    extends ExpressionClassBuilder
    ActivationClassBuilder provides an interface to satisfy generation's common tasks in building an activation class, as well as a repository for the JavaFactory used to generate the basic language constructs for the methods in the class. Common tasks include the setting of a static field for each expression function that gets added, the creation of the execute method that gets expanded as the query tree is walked, setting the superclass.

    An activation class is defined for each statement. It has the following basic layout: TBD See the document \\Jeeves\Unversioned Repository 1\Internal Technical Documents\Other\GenAndExec.doc for details.

    We could also verify methods as they are added, to have 0 parameters, ...

    • Field Detail

      • targetResultSetField

        private LocalField targetResultSetField
      • cursorResultSetField

        private LocalField cursorResultSetField
      • closeActivationMethod

        private MethodBuilder closeActivationMethod
    • Constructor Detail

      • ActivationClassBuilder

        ActivationClassBuilder​(java.lang.String superClass,
                               CompilerContext cc)
                        throws StandardException
        By the time this is done, it has constructed the following class:
            final public class #className extends #superClass {
                        // public void reset() { return; }
                        protected ResultSet doExecute() throws StandardException {
                                // statements must be added here
                        }
              public #className() { super(); }
            }
         
        Throws:
        StandardException - thrown on failure
    • Method Detail

      • getPackageName

        public java.lang.String getPackageName()
        Get the package name that this generated class lives in
        Specified by:
        getPackageName in class ExpressionClassBuilder
        Returns:
        package name
      • finishExecuteMethod

        void finishExecuteMethod()
        An execute method always ends in a return statement, returning the result set that has been constructed. We want to do some bookkeeping on that statement, so we generate the return given the result set. Upon entry the only word on the stack is the result set expression
      • addCursorPositionCode

        void addCursorPositionCode()
        Updatable cursors need to add a getter method for use in BaseActivation to access the result set that identifies target rows for a positioned update or delete.

        The code that is generated is:

        
          public CursorResultSet getTargetResultSet() {
                    return targetResultSet;
          }
        
          public CursorResultSet getCursorResultSet() {
                        return cursorResultSet;
          }
         
      • rememberCursorTarget

        void rememberCursorTarget​(MethodBuilder mb)
        Updatable cursors need to add a field and its initialization for use in BaseActivation to access the result set that identifies target rows for a positioned update or delete.

        The code that is generated is:

        
          private CursorResultSet targetResultSet;
        
         
        The expression that is generated is:
        
          (ResultSet) (targetResultSet = (CursorResultSet) #expression#)
         
      • rememberCursor

        void rememberCursor​(MethodBuilder mb)
        Updatable cursors need to add a field and its initialization for use in BaseActivation to access the result set that identifies cursor result rows for a positioned update or delete.

        The code that is generated is:

        
          private CursorResultSet cursorResultSet;
        
         
        The expression that is generated is:
        
          (ResultSet) (cursorResultSet = (CursorResultSet) #expression#)
         
        The expression must be the top stack word when this method is called.
      • getCloseActivationMethod

        MethodBuilder getCloseActivationMethod()