This section describes some basic guidelines for building a Java program using the Host Access Beans. For information on how to use the Host Access Beans in a JavaBean Visual Development Environment such as Sun's BeanBox or IBM's VisualAge for Java, see Using Host Access Beans in Visual Development Environments.
This section does not cover all the topics necessary to use your Host Access Beans program in a browser. For topics such as security and making classes visible in the browser environment, please see your browser documentation.
If you have created customized screens with Screen Customizer, you can display the customized screens with your CustomTerminal bean program. All customized screen files are contained in the custom subdirectory of the directory where Screen Customizer was installed. To use the customized screens, the custom directory and its entire contents must be copied to the same location as your CustomTerminal bean program.
Java programs that use the Host Access Beans must import the Host Access Beans packages to obtain class definitions and other compile-time information. The Host Access Beans packages can be imported into a Java source file using the following statements:
import com.ibm.eNetwork.beans.HOD.*; import com.ibm.eNetwork.beans.HOD.event.*;
For Screen customizer, you should import the following two packages:
import com.ibm.hi.customizer.beans.*; import com.ibm.hi.customizer.beans.event.*;
Some Host Access Beans methods require use of Host Access Class Library (HACL) constants. To use the HACL classes, Java programs must import the Host Access Class Library package by using the following statement:
import com.ibm.eNetwork.ECL.*;
The main Host Access Beans jar (Java Archive) files are habeans.jar and habeansnlv.jar. The main Screen Customizer Beans jar files are scbeans.jar and scbeansnlv.jar There are also several support jar files shipped with the Host Access Beans. The jar file format allows for packaging of classes, images, audio, and other files into a single file. It also allows for the separation of function for faster downloading. The jar files for the Host Access Beans are now located in the C:\Program Files\IBM\Host Access Toolkit\toolkit\jars directory, where C:\Program Files\IBM\Host Access Toolkit is the default install subdirectory chosen at installation time.
The full HACL support (except for a few noted exceptions) is shipped in two jar (Java Archive) files - habeans.jar (which contains English support) and habeansnlv.jar (which contains English plus all other language support). These files are suitable for Bean Builder environments and for writing Java applications. However, since they are not signed, they are not suitable for downloading over the web through a web browser.
For downloading HACL applets, the HACL support has been divided into several smaller signed "component" archive files. Both jar files (which are used in Netscape and Appletviewer environments) and cab files (which are used in Microsoft Internet Explorer environments) are provided. Since download delays are important in web browser environments, the "component" archive files will allow users to specifiy only those components which will actually be used and will avoid costly delays of downloading support that will never be used. To further optimize download times, release versions of the components are also provided.
The release versions of the components have the trace code removed which means they will be smaller and download faster than their debug counterparts. Most users will predominantly use the release versions of the components for web environments and only use the debug versions when problem determination is required. For Java application environments, users can use either release or debug components (or even the habeans.jar file) since download times are not a factor.
Most components have debug and release versions. However, some components, such as host code pages, only have a release version. Except for the host code page archives, you cannot mix some release versions and some debug versions. If problem determination is needed, or you are using debug components since download times are not important, you must use all debug components.
The table shown below shows all the different components, their release and debug names, and the components that they depend on:
The following table shows the component names for the host code pages:
All applications will use the habase (or habeans) and hacp archive files since those contain the "core" HACL files and "core" codepage files respectively.
To successfully compile and run your application, the CLASSPATH environment variable must be updated to include the jar files needed by your application. For example, if you need 5250 file transfer, you would need to include ha5250xn.jar, haxfern.jar, hamacrtn.jar in your CLASSPATH. You can also set the classpath using the Java compiler's '-classpath' parameter when compiling your application.
To find the HACL classes in the jar file, the classpath variable (or -classpath parameter) must point directly to the jar files. For example, if your application uses 3270 and SSL functions, and the jar files are located in the c:\jars directory, the classpath should look like this:
CLASSPATH=c:\jars\habasen.jar;c:\jars\hacp.jar;c:\jars\ha3270n.jar;c:\jars\hassln.jar
In Personal Communications,
there is only one jar file, pcseclj.jar. The jar is located in the Host Access Toolkit installation directory,
usually C:\Program Files\IBM\Host Access Toolkit. This jar is equivalent to habeansnlv.jar. Most of the
other support functions are available using the appropriate session configuration parameters in Personal Communications.
When an applet that uses the Host Access Beans is run in a browser environment, the browser must be able to find the Host Access Beans classes. See your browser documentation for information on how to expose classes in the browser environment.
When running an applet using the appletviewer
or running your program as an application,
you need to make sure the CLASSPATH environment variable contains the fully qualified path name of the Host Access
Beans jars used.