ABAP_to_the_Future

14
Shared Memory
agrees with the database contents. (The term invalidate here has the same meaning
as when used in relation to SAP database tables that use buffering.)
You will have seen by now that there are three settings scattered throughout the
screen that all relate filling up the root class with data the first time it is accessed:
Aut. Area Creation , Constructor Class , and Area Structure . If these three
fields are not consistent, then you get all sorts of error messages.
The Lifetime option at the bottom enables you to expire certain shared memory
areas if they have not been read for (as an example) 180 minutes, thus freeing up
memory. You usually would not want to do this, unless maybe you have objects
which were only accessed at certain times of the year (which does not seem very
likely).
When you are happy with the settings you have defined, click the Save button to
create the shared memory area. You will see messages popping up at the bottom
of the screen telling you that a class with the same name as the area is being generated:
ZCL_MONSTER_SHMO, in this case.
As mentioned earlier, you do not have to add any of your own custom coding
into the broker class. Each broker class is generated automatically with 99% identical
code; some small parts change based on the choices you made during the
SHMA transactions. For example, in the Attributes tab, as shown in Figure 14.6,
you can see that some of the attributes (such as the name of the root class) have
been set to the values you just entered.
Figure 14.6 Broker Class Attributes
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