The following are the integration frameworks that have been released for ABAP cloud development:

SOAP consumption: This framework allows you to consume SOAP web services from ABAP cloud applications. You can use the ABAP Development Tools in Eclipse to create a service consumption model based on a WSDL file or URL. The service consumption model generates the required ABAP artifacts, such as proxy classes, data types, and constants, to access the web service.You can then use the proxy classes to call the web service operations from your ABAP code1

Business Events: This framework allows you to publish and subscribe to business events from ABAP cloud applications. Business events are messages that represent a change in the state of a business object or process. You can use the ABAP Development Tools in Eclipse to create a business event definition based on a CDS view entity or a projection view. The business event definition specifies the event key, the event payload, and the event metadata.You can then use the ABAP Messaging Channel (AMC) framework to publish and subscribe to business events using the AMC API2

OData services: This framework allows you to expose and consume OData services from ABAP cloud applications. OData is a standardized protocol for creating and consuming RESTful APIs. You can use the ABAP RESTful Application Programming Model (RAP) to create OData services based on CDS view entities or projection views. The RAP framework generates the required OData metadata and runtime artifacts, such as service definitions, service bindings, and service implementations. You can then use the SAP Gateway framework to register and activate your OData services.You can also use the ABAP Development Tools in Eclipse to consume OData services from other sources using the service consumption model3

The other integration frameworks are not released for ABAP cloud development, as they are either not supported or not recommended for cloud scenarios. These frameworks are:

CDS Views: CDS views are not an integration framework, but a data modeling framework. CDS views are used to define data models based on database tables or other CDS view entities. CDS views can have associations, aggregations, filters, parameters, and annotations.CDS views can also be used as the basis for other integration frameworks, such as OData services or business events4

Business Add-ins (BAdls): BAdls are not supported for ABAP cloud development, as they are part of the classic ABAP enhancement framework. BAdls are used to implement custom logic in predefined enhancement spots in the standard SAP code. BAdls are not compatible with the cloud strategy and the clean core paradigm, as they modify the SAP code and can cause upgrade and maintenance issues. For ABAP cloud development, SAP recommends using the key user extensibility tools or the side-by-side extensibility approach instead of BAdls.

Based on the following code, the variable type of connection_full is a structure. A structure is a complex data type that consists of a group of related data objects, called components, that have their own data types and names. A structure can be defined using the TYPES statement or based on an existing structure type, such as a CDS view entity or a CDS DDIC-based view. In this case, the variable connection_full is declared using the TYPE addition, which means that it has the same structure type as the CDS view entity /DMO/I_Connection. The CDS view entity /DMO/I_Connection is a data model view that defines a data model based on the database table /DMO/Connection. The CDS view entity /DMO/I_Connection has the following components: carrid, connid, airpfrom, airpto, distance, and fltime. Therefore, the variable connection_full has the same components as the CDS view entity /DMO/I_Connection, and each component has the same data type and length as the corresponding field in the database table /DMO/Connection.

The nested join is evaluated from the top to the bottom in the order of the ON conditions. This means that the join expression is formed by assigning each ON condition to the directly preceding JOIN from left to right. The join expression can be parenthesized implicitly or explicitly to show the order of evaluation. In this case, the implicit parentheses are as follows:

SELECT * FROM (a INNER JOIN (b INNER JOIN c ON b~c = c~c) ON a~b = b~b)

This means that the first join expression is b INNER JOIN c ON b~c = c~c, which joins the columns of tables b and c based on the condition that b~c equals c~c. The second join expression is a INNER JOIN (b INNER JOIN c ON b~c = c~c) ON a~b = b~b, which joins the columns of table a and the result of the first join expression based on the condition that a~b equals b~b. The final result set contains all combinations of rows from tables a, b, and c that satisfy both join conditions.

In RESTful Application Programming, a business object contains two main parts: a CDS view and a behavior definition1.

A . CDS view: A CDS view is a data definition that defines the structure and the data source of a business object. A CDS view can consist of one or more entities that are linked by associations or compositions. An entity is a CDS view element that represents a node or a projection of a business object.An entity can have various annotations that define the metadata and the semantics of the business object2.

B . Behavior definition: A behavior definition is a source code artifact that defines the behavior and the validation rules of a business object. A behavior definition can specify the standard CRUD (create, read, update, delete) operations, the draft handling, the authorization checks, and the side effects for a business object.A behavior definition can also define custom actions, validations, and determinations that implement the business logic of a business object3.

The following are not parts of a business object in RESTful Application Programming, because:

C . Authentication rules: Authentication rules are not part of a business object, but part of a service binding. A service binding is a configuration artifact that defines how a business object is exposed as an OData service.A service binding can specify the authentication method, the authorization scope, the protocol version, and the service options for the OData service4.

D . Process definition: Process definition is not part of a business object, but part of a workflow. A workflow is a business process that orchestrates the tasks and the events of a business object. A workflow can be defined using the Workflow Editor in the SAP Business Application Studio or the SAP Web IDE.A workflow can use the business object's APIs to trigger or consume events, execute actions, or read or update data5.

The predicate condition that can be used to ensure that the CAST will work is IS INSTANCE OF. The IS INSTANCE OF predicate condition checks whether the operand is an instance of the specified class or interface. This is useful when you want to perform a downcast, which is a conversion from a more general type to a more specific type. A downcast can fail if the operand is not an instance of the target type, and this can cause a runtime error.Therefore, you can use the IS INSTANCE OF predicate condition to check whether the downcast is possible before using the CAST operator12. For example:

The following code snippet uses the IS INSTANCE OF predicate condition to check whether the variable g_super is an instance of the class lcl_super. If it is, the CAST will work and the variable g_sub1 will be assigned the value of g_super.

DATA: g_super TYPE REF TO lcl_super, g_sub1 TYPE REF TO lcl_sub1. IF g_super IS INSTANCE OF lcl_super. g_sub1 = CAST #( g_super ). g_sub1->method( ... ). ENDIF.

You cannot do any of the following:

IS SUPPLIED: The IS SUPPLIED predicate condition checks whether an optional parameter of a method or a function module has been supplied by the caller. This is useful when you want to handle different cases depending on whether the parameter has a value or not.However, this predicate condition has nothing to do with the CAST operator or the type of the operand12.

IS NOT INITIAL: The IS NOT INITIAL predicate condition checks whether the operand has a non-initial value. This is useful when you want to check whether the operand has been assigned a value or not.However, this predicate condition does not guarantee that the CAST will work, because the operand may have a value but not be an instance of the target type12.

IS BOUND: The IS BOUND predicate condition checks whether the operand is a bound reference variable. This is useful when you want to check whether the operand points to an existing object or not.However, this predicate condition does not guarantee that the CAST will work, because the operand may point to an object but not be an instance of the target type12.