Installing Universal Services
The DDL files in the included download
bundle create the necessary objects in DB2, and the script create the
.war file, which you can then deploy to the Web server.
The contents of the download bundle are shown in Figure 3:
Figure 3. Universal
Services download bundle
The only necessary configuration parameter is the location name of your
DB2. You also, however, have the option to change the names of the DB2
objects creator, table, and columns as command line arguments.
The only .war component affected by customization is the config.xml
file, which holds the SQL statements or operations supplied by the Web
service, and for Tomcat, the context.xml file, which holds the data
source definition. All the other files are included in the
download bundle and added to the .war
file unaltered.
The steps required for installation therefore include:
- Create table and UDF in DB2
- Configure script with table names and connection properties
- Run script to generate .war file
- Deploy .war file to Web server
Create objects in DB2
You need a table with the following columns:
Listing 1. Columns of table DB2ADMIN.SAMPLETABLE
ID INTEGER GENERATED ALWAYS AS IDENTITY
COMMENT VARCHAR(1000)
XMLDATA XML |
The names of the table and the columns are immaterial as long as the
format is correct. Also, the table can contain additional columns;
they just won't be referenced by Universal Services. If you do not
have a table of your own that you want to use, the DDL for the table
above is in the file createTable.txt.
The user-defined function is written in Java language. It takes as
input an XPath expression, an ID, a table name, and column names, and
returns the result of applying the XPath expression to an XML
document, namely the one in the row of the table with the supplied
ID.
A Java UDF consists of a Java load module and the DDL definition. The
Java load module can either be installed into the DB2 catalog or into
the Java directories in Unix System Services. This tutorial follows
the recommended praxis of installing it into the DB2 catalog. To this
end, this tutorial supplies a small Java technology program that calls
the stored procedure SQLJ.DB2_INSTALL_JAR. You could also call the
stored procedure from Data Studio.
To install the UDF, perform the following tasks:
- Modify supplied Java technology program uploadJar.java with the
following information:
- <hostname>, <port no>, and
<location name> of the DB2 subsystem. This
is the usual connection information needed when connecting
to a DB2 subsystem.
- <userid> and <password> for a
user with the privileges needed to install a JAR into the
DB2 catalog.
- The path to the JAR file if Universal Services was not
installed in the root directory of the C: drive.
- Compile and run the program:
- Start a command line in Windows.
- Navigate to the directory UniversalServicesZ.
- Enter the command
javac
uploadJar.java to
compile.
- Enter the command
java
uploadJar to run.
- Create the user-defined function DB2ADMIN.XPATHXML:
- Modify XPathDDL.txt. You must provide the name for the WLM
environment used for Java routines in your environment. In
the supplied DDL, it has the value DSN9WLMJ.
- Run DDL in XPathDDL.txt, in, for example, SPUFI.
Configure and generate .war file
You perform both the configuration and the generation by the script
configure for zOS.bat. You perform the configuration by calling a Java
program with the values for:
- Table creator, table name, column names (these will be used in the
SQL scripts for insert, update, delete, select, and query)
- DB2 location name (this is used to define a connection if the Web
server used is Tomcat)
The Java program generates the files config.xml and context.xml.
Afterwards, the Web archive is created by jar'ing these files with the
other supplied files. The result is the file
UniversalServices.war.
Deploy to the Web server
The actual steps needed for deployment depends on which Web server is
used. In each case, you need to:
- Configure the data source (in other words, the connection to the
DB2 subsystem where the data reside)
- Deploy UniversalServices.war to the runtime environment of the Web
server
Table 1 summarizes the information needed to
configure the data source—regardless of which Web server is
used. This information is needed whenever a remote connection is made
to DB2 through DB2 Connect or a type 4 JDBC driver.
For illustration purposes, let's use the (non-existent) values DSN9 for
<db2 name>, 9.123.45.678 for <host name>,
446 for <port no>, and db2admin for
<userid>. You must supply your own values for your
subsystem.
Table 1. Data source definition
information
| Element | Description |
|---|
| <db2 name> | The location name of your DB2 subsystem | | <host name> | The name of your z/OS system (could be a logical name or an
IP-address) | | <port no> | Port number of the DB2 subsystem | | <username> | User id used for the connection | | <pwd> | Pwd for user id used for connection |
The next section provides a detailed description of deployment with
each of the Web servers.
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