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"This variant of the statement CLASS is used to make the class class known, regardless of the location of the actual definition of the class in the program. It does not introduce a declaration part and must not be ended using ENDCLASS.

Example: CLASS c1 DEFINITION DEFERRED.
One example of using the addition DEFERRED PUBLIC would be a type group in which a reference type is declared with a reference to a global class, which itself contains components with references to this reference type. In this situation, the entire class cannot be loaded before the type group, since the types are not yet known. After the statement DEFERRED PUBLIC, however, the class name can be specified after REF TO without the class having been loaded previously."
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Static methods are methods which can be called irrespective of the class instance. Only static attributes and static events can be accessed within the Static method. Memory is allocated once. Instance methods are methods which can be ONLY called using the object reference. Instance methods can access instance attributes and instance events. Memory is allocated for each object instance.