NETJVM 

The Constraints Paragraph

The Constraints paragraph allows specification of properties of parameters of a parameterized class, and therefore allows the use of methods or properties on data items whose type is specified as that parameter.

General Format


Syntax for the CONSTRAINTS paragraph

Syntax Rules

  1. Parameter-name-1 must be a parameter of the class in which this Constraints paragraph is specified.

General Rules

  1. If the IMPLEMENTS phrase is specified, parameter-name-1 must be of a class that implements the interface interface-name-1.
  2. If the INHERITS phrase is specified, parameter-name-1 must inherit directly or indirectly from class-name-1.
  3. If the NEWABLE phrase is specified, the class of parameter-name-1 must include a constructor with no parameters.
  4. If VALUE TYPE or VALUETYPE is specified, the type of parameter-name-1 must be a value type. If REFERENCE TYPE is specified, the type of parameter-name-1 must be a reference type.
  5. Items whose type is specified as parameter-name-1 may be specified where an item of class class-name-1 or interface-name-1 is required.
  6. Items whose type is specified as parameter-name-1 have all the methods and properties of a class-name-1 and interface-name-1