The code snippet shows a downcast using the CAST operator, from a superclass reference loanimal to a subclass reference locat. This operation is only valid at runtime if the object instance currently referenced by loanimal is of type lclcat or one of its subclasses. The predicate expression IS INSTANCE OF is specifically designed to check this condition. By using IF loanimal IS INSTANCE OF lclcat, a developer can verify the type compatibility before attempting the cast, thereby preventing the CXSYMOVECASTERROR exception that would occur if the check failed.

A. IS SUPPLIED: This predicate is used within methods to check if an optional formal parameter was provided by the caller; it is unrelated to object type checking.

B. IS NOT INITIAL: This only verifies that the reference variable points to an object, but it does not guarantee that the object is of the correct type for a successful downcast.

D. IS BOUND: This is a synonym for IS NOT INITIAL. It confirms that a reference is pointing to an object but does not check for type compatibility required by the CAST.

1. SAP Help Portal - ABAP Keyword Documentation

IS INSTANCE OF: "The relational expression oref IS INSTANCE OF class|if checks whether the object reference in the object reference variable oref points to an object whose class is the class class or a subclass of class..." This directly supports using IS INSTANCE OF to check type compatibility before a downcast.

2. SAP Help Portal - ABAP Keyword Documentation

CAST - Down Cast: "In a down cast

the static type of the source variable is a superclass of the static type of the target variable. For the assignment to be successful

the dynamic type of the source variable (the class of the object to which it refers) must be the same class as the static type of the target variable

or one of its subclasses. ... If the cast is not possible

the handleable exception CXSYMOVECASTERROR is raised." This explains the risk of the CAST operation and the condition required for it to succeed

which is precisely what IS INSTANCE OF checks.

The ABAP statement DATA connectionfull TYPE /DMO/IConnection. declares a work area, which is a structure. In ABAP, when a CDS view entity (like /DMO/IConnection) is used directly with the DATA ... TYPE syntax, the system creates a structured data object. The components of this structure directly correspond to the fields defined in the projection list of the specified CDS view. This variable is suitable for holding a single row of data from the view.

A. Simple variable: A simple variable holds a single elementary value (e.g., integer, character). A CDS view represents a collection of multiple fields, not a single value.

C. Internal Table: To declare an internal table based on the CDS view, the syntax must include the TABLE OF addition, for example: DATA connectionfull TYPE TABLE OF /DMO/IConnection..

1. SAP Help Portal

ABAP Keyword Documentation

DATA - TYPE: "If dtype is a structured data type from ABAP Dictionary or a public visibility section of a global class

a structured data object dobj (a structure) is declared." A CDS view is treated as a structured data type from the ABAP Dictionary in this context. (See section: DATA dobj TYPE dtype ...)

2. SAP Help Portal

ABAP Keyword Documentation

TYPES - DATA: This document explains the relationship between data types and data objects. It clarifies that a DATA statement creates a data object with the attributes of a specified data type. Using a CDS view as the type results in a structured data object. (See section: TYPES - DATA)

3. SAP Help Portal

ABAP Keyword Documentation

SELECT - INTO: Examples in this section frequently show a SELECT SINGLE ... INTO @DATA(wa) or SELECT ... INTO @wa where wa is declared as DATA wa TYPE cdsentity.. This demonstrates the use of a variable typed on a CDS entity as a work area (structure) to receive a single row. (See various examples under the SELECT statement documentation).

The ABAP Cloud development model enforces a strict "public interface" contract. Only SAP objects (like classes, interfaces, CDS views, etc.) that are explicitly released for cloud development can be used in custom code. This rule is enforced at the earliest possible stage: the syntax check. When a developer tries to reference an object that is not part of the released public API, the ABAP compiler in the ABAP Development Tools (ADT) will immediately raise a syntax error, preventing the code from being activated. This ensures that all custom code is compliant, upgrade-stable, and adheres to the cloud development paradigm.

A. It compiles, but ATC warns only during transport: This is incorrect. The check is a fundamental compiler rule, not a post-development quality check. The code will not compile or activate, so it cannot reach the transport stage.

C. It works if you add the package as a friend in the interface: This is incorrect. The "friend" relationship in ABAP Objects is for granting access to private/protected components and does not override the fundamental API release and visibility rules of the ABAP Cloud model.

D. It runs but raises CXNOAUTHORITY at first call: This is incorrect. The issue is a compile-time violation, not a runtime authorization failure. The code would never be in a runnable state to trigger any exception.

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1. SAP Help Portal - ABAP RESTful Application Programming Model: In the "ABAP Language Versions" documentation

it is specified for the ABAP for Cloud Development version: "A restricted syntax is used... A restricted set of repository objects from SAP can be used... The use of a non-released API of an SAP object produces a syntax error."

Source: SAP Help Portal

ABAP Keyword Documentation

section on ABAP Language Versions.

2. SAP Help Portal - Released APIs: "In ABAP Cloud

you can only use released SAP APIs in your custom code. The ABAP compiler checks whether you only use released SAP APIs. If you use an unreleased SAP API

you get a syntax error."

Source: SAP Help Portal

ABAP Platform

section on Development in ABAP Cloud -> Released APIs.

3. openSAP Course - Building Apps with the ABAP RESTful Application Programming Model (RAP): Week 1

Unit 3

"Getting Started with ABAP Development Tools

" explains that the ADT environment enforces the ABAP Cloud rules

and violations against the released object model are flagged as syntax errors during development.

Source: openSAP Courseware

"Building Apps with the ABAP RESTful Application Programming Model (RAP)".

The performance of accessing an internal table depends on its type and how the key is specified.

- Sorted Tables: These tables are internally sorted by their primary key. Access using a binary search algorithm is possible if the specified key fields constitute a left-aligned, gapless part of the primary key. This makes access very fast (logarithmic time complexity). Therefore, specifying the key completely or partially from the left results in fast access.

- Hashed Tables: These tables use a hash algorithm to calculate a record's address based on its full primary key. This provides the fastest possible access (near-constant time complexity). However, this method requires all primary key fields to be specified; partial key access is not possible for the primary key.

C. In a standard internal table, specifying the primary key partially from the left without gaps.

Standard tables are searched linearly by default, which is slow for large tables. Fast access requires a secondary sorted key.

D. In a hashed internal table, specifying the primary key partially from the left without gaps.

Accessing a hashed table via its primary key requires all key fields to be specified to compute the hash value; partial keys are not supported.

1. SAP Help Portal

ABAP Keyword Documentation - READ TABLE - itabkey:

For Sorted Tables: "If the specified components form a left-aligned part of the table key

the search is binary... If not

the search is linear

as in standard tables." This supports answers A and B.

For Hashed Tables: "When a hashed table is accessed using WITH TABLE KEY

all components of the table key must be specified... The search uses the hash algorithm of the internal table." This supports answer E and invalidates D.

For Standard Tables: "The search is linear. The runtime is in linear relation to the number of table rows." This invalidates answer C.

2. SAP Help Portal

ABAP Keyword Documentation - TYPES - TABLE OF:

Section on WITH ... KEY: This documentation details the definition and access characteristics of each table kind. It explicitly states that sorted keys allow binary searches on initial parts of the key

while hashed keys require a full key specification for hash access. This provides foundational knowledge supporting the correct answers.

A. The statement goif1 = NEW cl1( ... ) is valid. It creates an instance of class cl1 and assigns its reference to the interface reference variable goif1. This is a permitted up-cast because class cl1 publicly implements the interface if1.

B. The interface reference variable goif1 has the static type if1. Therefore, it can be used to access all components defined in the interface if1, including the method m1. The syntax goif1->m1( ... ) is the correct way to call this method.

C. The class reference variable gocl1 can be used to call methods from interfaces that the class cl1 implements. To avoid ambiguity, the interface name must be specified using the interface component selector (~). Thus, gocl1->if1~m1( ... ) is the correct syntax.

D. To call an interface method via a class reference, the interface name must be used as a prefix (if1~m1), unless an alias has been defined. No alias is defined in the code.

E. An interface reference variable (goif1) can only access components defined within that interface. The method m2 is a component of the class cl1 and is not part of the interface if1.

1. SAP Help Portal

ABAP Keyword Documentation

NEW - Instance Operator:

Regarding option A: "The static type of lhs [the left side

goif1] must be more general than or identical to the data type type [cl1] specified after NEW or the data type of .... In other words

the reference in type must be able to be assigned to lhs in an up cast." Since cl1 implements if1

this condition is met.

2. SAP Help Portal

ABAP Keyword Documentation

Polymorphism - Using Interface Reference Variables:

Regarding option B: "An interface reference variable iref allows a user to access the interface components of the object to which it points." This confirms that goif1 can access method m1.

Regarding option E: This same principle confirms that goif1 cannot access class-specific components like m2

as they are not part of the interface's definition.

3. SAP Help Portal

ABAP Keyword Documentation

CALL METHOD - Statically:

Regarding option C and D: "If meth is an interface method

the name of the interface intf and the interface component selector (~) must be specified before the name of the method meth." This validates the syntax in option C and invalidates the direct call in option D (in the absence of an alias).