【IT168 技术文章】
首先，按照惯例，上例子程序的类图
测试程序如下：
REPORT ZBOBO_DP_003_RE .
*The class and interface for this program
include zbobo_dp_003_if_cl.
*Reference data for drink definition
data: dr_ref type ref to drink.
*Temp reference for decorator
data:tdr type ref to drink.
start-of-selection.
*-------------------start decorate---------------*
* Narrowing cast
* Create darkroast object
create object tdr type darkroast.
* Make dr_ref point to the object darkroast
* And this is the need to be decorated material
dr_ref = tdr.
* Use mocha to decorate object darkroast
create object tdr type mocha
exporting dr = dr_ref. "This dr_ref is darkroast
dr_ref = tdr.
* Use soy to decorate object mocha&darkroast
create object tdr type soy
exporting dr = dr_ref. "This dr_ref is mocha
dr_ref = tdr.
* Use whip to decorate object soy&mocha&darkroast
create object tdr type whip
exporting dr = dr_ref. "This dr_ref is soy
dr_ref = tdr.
*-------------------end decorate---------------*
* Define data which used to display data
data: ls type string,lf type f.
* Get description
ls = dr_ref->getdesc( ).
* Get cost
lf = dr_ref->cost( ).
* Display result
write: / ls, ':$',lf decimals 2 exponent 0.
*The class and interface for this program
include zbobo_dp_003_if_cl.
*Reference data for drink definition
data: dr_ref type ref to drink.
*Temp reference for decorator
data:tdr type ref to drink.
start-of-selection.
*-------------------start decorate---------------*
* Narrowing cast
* Create darkroast object
create object tdr type darkroast.
* Make dr_ref point to the object darkroast
* And this is the need to be decorated material
dr_ref = tdr.
* Use mocha to decorate object darkroast
create object tdr type mocha
exporting dr = dr_ref. "This dr_ref is darkroast
dr_ref = tdr.
* Use soy to decorate object mocha&darkroast
create object tdr type soy
exporting dr = dr_ref. "This dr_ref is mocha
dr_ref = tdr.
* Use whip to decorate object soy&mocha&darkroast
create object tdr type whip
exporting dr = dr_ref. "This dr_ref is soy
dr_ref = tdr.
*-------------------end decorate---------------*
* Define data which used to display data
data: ls type string,lf type f.
* Get description
ls = dr_ref->getdesc( ).
* Get cost
lf = dr_ref->cost( ).
* Display result
write: / ls, ':$',lf decimals 2 exponent 0.
