Using the Servlet

Syntax: How to Call the Servlet From a Hyperlink

<A HREF="/alias/WFServlet?IBIF_ex=procedure[&var=value[&var=value]...]">text</A>

where:

alias

Points to the directory in which the WebFOCUS Servlet is located. A web server uses an alias to provide a logical name for a physical directory. The default alias is ibi_apps. It is set during WebFOCUS installation and configuration.

To call the WebFOCUS Servlet on another web server, specify a fully qualified URL, such as:

http://web_server/ibi_apps/WFServlet...

procedure

Is the name of the procedure to run.

var=value

Is a variable and its corresponding value. The call can include both HTTP environment variables and application variables passed to the procedure.

You can pass more than one variable-value pair, but do not include a space between pairs. Use an ampersand (&) as a delimiter to separate each variable-value pair.

If a value contains an embedded blank, substitute a plus sign (+) or the characters %20 for the blank.

text

Is the text on the launch page that serves as the hyperlink that runs the procedure.

Note: The maximum length of the URL can be 4K or 4,096 bytes. There is no limit on the number of the parameters, but their total length cannot exceed 4K.

Example: Calling the Servlet From a Hyperlink

This example creates a launch page with four hyperlinks. Each hyperlink calls the Servlet to pass:

The name of a procedure to run.
Two values that the procedure requires.

Note: For information on where to store the files created in this example, see Defining and Allocating WebFOCUS Files.

Create a procedure named CSALES. It generates a dynamic report that shows total unit and dollar sales for a category and region.

Procedure: CSALES.FEX

TABLE FILE GGSALES
HEADING
"&CATEGORY Sales for &RGN Region"
SUM UNITS AND DOLLARS
WHERE (CATEGORY EQ '&CATEGORY') AND (REGION EQ '&RGN');
ON TABLE SET PAGE-NUM OFF
ON TABLE SET STYLE *
TYPE=REPORT, GRID=OFF,$
ENDSTYLE
END

Create a launch page named CSALES. Each instance of the A HREF code calls the WebFOCUS Servlet and passes it the name of the procedure, CSALES. Each instance also passes the value Coffee for CATEGORY, and a value for RGN (Midwest, Northeast, Southeast, or West). The hyperlinks on the launch page prompt the user for the region of interest.

Launch Page: CSALES.HTM

<HTML>
<HEAD>
<TITLE> WebFOCUS Report </TITLE>
</HEAD>
<BODY>
<H4 ALIGN=CENTER>Coffee Sales by Region</H4>
<HR>
<P><FONT SIZE=+2></FONT><BR>
<FONT SIZE=+1>Select a region:</FONT>
</P>
<UL TYPE=SQUARE>
<LI>

<A HREF="/ibi_apps/WFServlet?IBIF_ex=csales&CATEGORY=
Coffee&RGN=Midwest">Midwest</A>

<LI>

<A HREF="/ibi_apps/WFServlet?IBIF_ex=csales&CATEGORY=
Coffee&RGN=Northeast">Northeast</A>

<LI>

<A HREF="/ibi_apps/WFServlet?IBIF_ex=csales&CATEGORY=
Coffee&RGN=Southeast">Southeast</A>

<LI>

<A HREF="/ibi_apps/WFServlet?IBIF_ex=csales&CATEGORY=
Coffee&RGN=West">West</A>

</UL>
</BODY>
</HTML>

Run the launch page in your browser. It will look similar to this:
Click the hyperlink Midwest to receive the report:

Reference: Conventions for Creating a Form

To begin and end a form, use the HTML <FORM tag.
To specify the name of the procedure to run, use the HTML <INPUT tag.
Include the desired controls on the form, such as text boxes, check boxes, or drop-down lists.
Include a Submit button to execute the Servlet and pass the values collected on the form to the procedure.

Example: Calling the Servlet From a Form

This example creates a launch page with a form that calls the Servlet to pass:

The name of a procedure to run.
Two values that the procedure requires. The form prompts the user for the first value with a one-line text box, and for the second value with radio buttons.

Note: For information on where to store the files created in this example, see Defining and Allocating WebFOCUS Files.

If you have not done so in a previous example, create a procedure named CSALES. It generates a dynamic report that shows total unit and dollar sales for the category and region requested by the user.
Procedure: CSALES.FEX
```
TABLE FILE GGSALES
HEADING
"&CATEGORY Sales for &RGN Region"
SUM UNITS AND DOLLARS
WHERE (CATEGORY EQ '&CATEGORY') AND (REGION EQ '&RGN');
ON TABLE SET PAGE-NUM OFF
ON TABLE SET STYLE *
TYPE=REPORT, GRID=OFF,$
ENDSTYLE
END
```

Create a launch page named SALES.HTM. It contains a form that calls the Servlet to pass the name of the procedure, CSALES. A one-line text box prompts the user for a value for CATEGORY, and radio buttons prompt for a value for RGN.

The form also contains a Submit button (labeled Run Report) and a Reset button (labeled Clear Form). When you prompt for user input on a form, you must include a Submit button.

Launch Page: SALES.HTM

<HTML>
<HEAD>
<TITLE> WebFOCUS Report </TITLE>
</HEAD>
<BODY>
<H4 ALIGN=CENTER>Sales Report by Category and Region</H4>
<HR>

<FORM ACTION="/ibi_apps/WFServlet" METHOD="get">
<INPUT NAME="IBIF_ex" VALUE="csales" TYPE="hidden">
<P ALIGN=LEFT NOWRAP><PRE>
<B>Enter category: </B><INPUT NAME="CATEGORY" TYPE="text" SIZE="6">
</PRE></P>
<P><PRE><B>Select region: </B>
<INPUT NAME="RGN" TYPE=RADIO VALUE=Midwest>Midwest
<INPUT NAME="RGN" TYPE=RADIO VALUE=Northeast>Northeast
<INPUT NAME="RGN" TYPE=RADIO VALUE=Southeast>Southeast
<INPUT NAME="RGN" TYPE=RADIO VALUE=West>West
</PRE></P>
<P>
<INPUT NAME="submit" TYPE=SUBMIT VALUE="Run Report"> 
<INPUT NAME="reset" TYPE=RESET VALUE="Clear Form">
</P>
</FORM>

</BODY>
</HTML>

Run the launch page in your browser. It will look similar to this:
In the Enter category field, type:
```
Coffee
```
Select the Southeast radio button.
Click Run Report to receive the report.

Using the Servlet

Reference: Requirements for WebFOCUS Servlet Configuration

Syntax: How to Call the Servlet From a Hyperlink

Example: Calling the Servlet From a Hyperlink

Syntax: How to Call the Servlet From a Form

Reference: Conventions for Creating a Form

Example: Calling the Servlet From a Form