Problem:
The demo attached contains 3 programs
One Java program which does SQL I-Os thru JDBC
One OO COBOL program which invokes the Java program above
( this OO COBOL program is a 'stub' between procedural COBOL and JAVA )
One procedural COBOL program which invokes the OO COBOL program above.
Resolution:
=======================
INTRODUCTION_1:
since the JAVA program does SQL I-Os using JDBC using an ODBC layer,
you need a DSN (Data Source Name ) called 'NetExpress Sample2' pointing to an ACCESS DataBase named SAMPLE.MDB ( delivered with .ZIP attached with this demo )
--> Config Panel->Administration tools->ODBC data sources
IF the DSN 'NetExpress Sample2' does'nt exist, create it
using an ACCESS Driver pointing to ACCESS DataBase named SAMPLE.MDB
=======================
INTRODUCTION_2:
As described above, the demo contains 3 programs
a Java one
named
Java_Jdbc_Access.java
a OO COBOL one
named
OOCOBOL.cbl
a procedural COBOL one named
proceduralCOBOL.cbl
in the FULL demo, proceduralCOBOL calls OOCOBOL which invokes Java_Jdbc_Access
Anyway, for test purposes, each program can be launched as a launcher
eg:
java Java_Jdbc_Access
runm OOCOBOL
runm proceduralCOBOL
=======================
STEP_1:
running the first STEP of the demo eg: java Java_Jdbc_Access
What does the Java code Java_Jdbc_Access do?
---->
First, open a Netx command prompt SET JAVA environment
Doc NE 4.0->Distributed Computing->Part 3: Java and COBOL->Overview&Setting Up the
Environment for Java and COBOL
http://supportline.microfocus.com/documentation/books/nx40/dipubb.htm
---->Java code: Java_Jdbc_Access
method main
updates public variables JDBC url & UserID & password
updates the SQL query which will be runned against the database
invokes a method named SQLIO()
closes the opened JDBC connection invoking the method CloseConnectionJDBC()
method SQLIO
loads the JDBC driver invoking the method JdbcOdbcDriverAvail()
opens a JDBC connection invoking the method getConnectionJDBC()
invokes the method doSQLQuery to proceed I-Os against the database
method doSQLQuery
creates a JDBC statement
[stmt = this.con.createStatement();
]
executes this statement
[ResultSet rs = stmt.executeQuery(SQLquery);]
note the result of the execution of this statement is returned in a ResultSet
which contains a "Collection" of rows of a table
saves the ResultSet just retrieved above in the public variable rs [this.rs = rs;]
displays the content of the ResultSet invoking the method displayResultSet(rs);
---->
Compile the java program Java_Jdbc_Access.java ( javac Java_Jdbc_Access.java )
run it: java Java_Jdbc_Access
The content of the table Customer should be displayed
( as in file Java_Jdbc_Access.log ... ( delivered with .ZIP attached with this demo )
=======================
STEP_2:
running the second STEP of the demo eg: runm OOCOBOL
-->first,in OOCOBOL.CBL, have the constant CALLERMODE()
set
--->
$SET constant CALLERMODE()
[ character $ in column 7 )
-->Cobol code OOCOBOL in launcher mode
creates an instance of the class Java_Jdbc_Access
(Comment 1)
updates public variables JDBC url & UserID & password
(Comment 1)
updates the SQL query which will be runned against the database
(Comment 1)
invokes a method named SQLIO()
(Comment 1)
invokes a method getrs to return the ResultSet retrieved in the method SQLIO()
!!!! Doc NE 4.0->Distributed Computing->Chapter 10: Calling Java from OO
COBOL->Accessing Java Variables
No need of hand written methods to access Java Static | public variables !!!
remember, as documented above
(method doSQLQuery .... saves the ResultSet just retrieved above in the public
variable rs [this.rs = rs;]
)
invokes Java methods on the ResultSet to retrieve its content and displays the content
closes the opened JDBC connection invoking the method CloseConnectionJDBC()
*
(Comment 1
* As int the main method of Java_Jdbc_Access
-->
Compile OOCOBOL ( COBOL OOCOBOL int() anim;
launch OOCOBOL rumm oocobol
The content of the table Customer should be displayed
( as in file oocobol..log ... ( delivered with .ZIP attached with this demo )
=======================
STEP_3:
running the full demo eg: proceduralCOBOL calls OOCOBOL which invokes Java_Jdbc_Access
-->first,in OOCOBOL.CBL, have the constant CALLERMODE()
unset
--->
*SET constant CALLERMODE()
[ character * in column 7 )
-->The only difference in OOCOBOL program depending on it's used in caller mode or called mode is
in caller mode:
the result of the SQL query is displayed on the screen
in called mode, the result of the SQL query is put in a LINKAGE group
-->Cobol code proceduralCOBOL
calls OOCOBOL passing to it 2 variables
1st one, named NumberOfRowsReturned, will contain when back from OOcobol in
proceduralCOBOL the number of table's rows rerurned
2nd one, named DCLcustomer which is a group with OCCURS, contains data retrieved
by the SQL query
display the content of the SQL data returned, displaying the content of the group
DCLCUSTOMER which contains data returned following the SQL I-Os
-->
Compile proceduralCOBOL ( COBOL proceduralCOBOL int() anim;
launch proceduralCOBOL: rumm proceduralCOBOL
The content of the table Customer should be displayed
( as in file proceduralCOBOL..log ... ( delivered with .ZIP attached with this demo )
=======================
STEP_4
For convenience, a Net Express project is delivered with this demonstration
:
=======================
You can see the JAVADOC of this demonstration in the subdir JAVADOC
after you unzipped the COBOtoJava_jdbc.zip
=======================
