a laboratory for teaching object-oriented thinking.mht

十篇国外的重要资料

<P><IMG src=3D"http://c2.com/doc/oopsla89/fig5.gif">=20
<P>Events drive the human interface by triggering Actions that sequence =
through=20
Screens. The actual format and sequence of screens will be determined by =
the=20
user-interface design and will probably vary from bank to bank. We offer =
objects=20
from which state-machine like interfaces can be built.=20
<P><IMG src=3D"http://c2.com/doc/oopsla89/fig6.gif">=20
<P>Screen objects correspond to the states and Action objects correspond =
to the=20
transitions. Screens may vary in how they dispatch Actions. Actions =
themselves=20
will vary in how they process events. Actions ultimately construct =
Transactions=20
to which they delegate the further operating of the bank machine=20
<P><IMG src=3D"http://c2.com/doc/oopsla89/fig7.gif">=20
<P><FONT size=3D-3>Permission to copy without fee all or pan of this =
material is=20
granted provided that the copies are not made or distributed for direct=20
commercial advantage, the ACM copyright notice and the title of the =
publication=20
and its date appear and notice is given that copying is by permission of =
the=20
Association for Computing Machinery. To copy otherwise, or to publish, =
requires=20
a fee and/or specific permission.=20
<P>01989 ACM 089791-333-7/89/0010/0001 $1.50 </FONT>
<P>
<HR>

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