"用IS INSTANCE OF关键字,判断当前记录指向的是圆形还是长方形实例,再用CAST进行强制类型转换,调用对应的面积计算方法。DATA(LO_CIRCLE) = NEW ZCL_CIRCLE( 1 ).DATA(ENTRY) = VALUE TY_SHAPE( SHAPE = LO_CIRCLE ).APPEND ENTRY TO LT_SHAPE.DATA(LO_RECTANGLE) = NEW ZCL_RECTANGLE( IV_HEIGHT = 1 ...
B.T.W., the new IS INSTANCE OF and CASE TYPE OF even work for initial reference variables. Then they check if an up cast is possible.This can be helpful for checking the static types of formal parameters or field symbols that are typed generically. Therefore IS INSTANCE OF is not only ...
如示例程序5.15所示,下转型是需要类型验证的,如"苹果"和"梨子"上转型为"水果"后,可以下转型为"苹果"或者"梨子"。在ABAP 7.5 版本后,可以使用 IS INSTANCE OF 操作符来判断具体的类对象的类型,对具体类型进行验证。 "示例程序5.15 REPORTzrep_cls_015. "定义素食类 CLASS zcl_vegetarian_foodDEFINITION. ENDCLA...
Instance Creation 代码语言:javascript 代码运行次数:0 运行 AI代码解释 START-OF-SELECTION. CREATE OBJECT o_main. Calling Methods 代码语言:javascript 代码运行次数:0 运行 AI代码解释 * The statement TRY must be used to define a block that CATCH the exceptions TRY. o_main->action( ). * The Stat...
这种实现方式,在LOOP里有IF ELSE判断,IS INSTANCE OF和CAST这三种非常丑陋的写法。将来如果要支持其他图形比如三角形的面积计算,又得在LOOP里添加新的ELSE分支,这违反了程序设计的开闭原则(对扩展开放,对修改封闭)。 采用CL_OBJECT_COLLECTION的多态实现
if the type or the length of the data stored is not identical with that of the target type. Exception group: LOCALIZATION_ERRORS (Common class:CX_SY_LOCALIZATION_ERROR) This group contains runtime errors that may occur when you switch to another text environment. Typical examples are if the...
Since I perform the request in an asynchronous mode, so the response of those five requests are processed and returned in parallel. How singleton behavior of Servlet is achieved The instance of requested Servlet will only be initialized when it is asked for the first time. The below two-fold...
instanceOf in ABAP Former Member 2006 Jul 24 3:15 PM 0 Kudos 482 SAP Managed Tags: ABAP Development Hi, does anybody know if there is an equivalent to the java instanceof in ABAP? (I.E: for checking if a given object is an insance of a certain class...) If so, ...
The instance of requested Servlet will only be initialized when it is asked for the first time. The below two-fold instance checking against null is a typical thread-safe implementation pattern for Singleton in Java. The method loadServlet in class StandardWrapper will call constructor of my samp...
IF <ls_out_tab>-inst IS INSTANCE OF zcl_paralell1. lo_instance_1 = CAST #( <ls_out_tab>-inst ). out->write( 'System time for instance 1:' ). LOOP AT lo_instance_1->get_time( ) ASSIGNING FIELD-SYMBOL(<lv_instance_1>). out->write( <lv_instance_1>...