IBM® zSeries Developer Kit for Linux®, Java(TM) 2 Technology Edition, Version 1.2.2 README

This README file provides information about the IBM zSeries Developer Kit for Linux®, Java(TM) 2 Technology Edition, Version 1.2.2 (Developer Kit for Linux). Use this README file if you want to use the Developer Kit for Linux to write Java applications and applets.

The Developer Kit for Linux has been tested with SuSE Linux 7.0.


Contents

  • Overview
  • Version compatibility
  • Installation requirements
  • Contents of the Developer Kit for Linux
  • The just-in-time (JIT) compiler
  • Configuring the Developer Kit for Linux
  • Installing additional fonts
  • Uninstalling the Developer Kit for Linux
  • Uninstalling the installable Red Hat Package Manager (RPM) package
  • Uninstalling the compressed Tape Archive (TAR) package
  • Euro symbol support
  • Unicode Support
  • Collation of Currency Symbols
  • Using the Developer Kit
  • PATH considerations
  • CLASSPATH considerations
  • Running applets with the Applet Viewer
  • Debugging applets with the Applet Viewer
  • Obtaining the IBM build and version number
  • Debugging Java applications
  • Java Platform Debugger Architecture (JPDA)
  • Java Debugger (JDB)
  • Switching the input method in DBCS languages
  • RMI over IIOP
  • Enhanced BigDecimal
  • Shipping Java applications
  • Troubleshooting
  • Known limitations
  • General Information
  • Information for Japanese users
  • Service and support for independent software vendors
  • Notices
  • Trademarks

  • Overview

    The Developer Kit for Linux is a development environment for writing applets and applications that conform to Sun's Java 1.2.2 Core Application Programming Interface (API).


    Version compatibility

    Applets that depend on Sun's Java 1.2.2 APIs work only on browsers that support Java 1.2.2 APIs.

    To see the document on compatibility at the click the link and follow the steps below:

    1. Click Products & APIs.
    2. Click Java(TM) 2 Platform, Standard Edition (J2SE(TM)) under Product Groups.
    3. Click Java(TM) 2 SDK, Standard Edition, v 1.2.2 under Current Releases.
    4. Click browsing online under J2SE 1.2.2 Documentation on the right.
    5. Click Version Compatibility with Previous Releases under Compatibility.

    Installation requirements

    Software requirements

    X11R6 3.3.x, provided by XFree86 Currently included in all of the supported products
    C Runtime Library (libc) version 2.1.3-176 or later Currently included in the supported products.

    If you do not have the C Runtime Library (libc) version 2.1.3-176 or later, you must upgrade before using the Developer Kit for Linux. To determine the level of glibc on your system, type the following from within any shell:

         rpm -q libc

    Linux kernel 2.2.16 or later Currently included in all of the supported products

    If you have a version of the Linux operating system that does not have kernel 2.2.16 or later, information on upgrading the kernel might be found at the following Web site: http://www.kernel.org/

    Hardware requirements


    Contents of the Developer Kit for Linux

    The following list describes the contents of the Developer Kit package.

    RUNTIME Environment - Classes (rt.jar)

    This file contains all of the compiled .class files for the platform and must remain zipped for the compiler and interpreter to properly access the class files within it.

    Tools

    The tools provided include:

    Java Documentation and Demos

    The following documentation and demos are included with the Developer Kit for Linux:

    README

    This file.

    COPYRIGHT

    Copyright notice for the Developer Kit for Linux software.

    LICENSE

    The LICENSE_xx.html file contains the license agreement for the Developer Kit for Linux software. (xx is an abbreviation for the language.)

    To view or print the license agreement, open the file in a Web browser.

    FIXES.LST

    A text file that describes any defects fixed after the initial release of this version.

    Note: This README file and the accompanying license, copyright files, and demo directory are the only documentation included in this Developer Kit for Linux. Click the link and follow the steps below to look at Sun's software documentation by visiting the Sun Web site, or possibly download Sun's Software documentation package:

    1. Click Products & APIs.
    2. Click Java(TM) 2 Platform, Standard Edition (J2SE(TM)) under Product Groups.
    3. Click Java(TM) 2 SDK, Standard Edition, v 1.2.2 under Current Releases.

    The documentation package is designed to be extracted into the Developer Kit for Linux software installation directory. If you download the zip file archive version, be sure to preserve the file path names when you extract the files from the archive. If you use pkunzip, specify the -d option.


    The just-in-time (JIT) compiler

    The Developer Kit for Linux does not include the IBM just-in-time (JIT) compiler (libjitc.so). The JIT compiler generates machine code dynamically for frequently used bytecode sequences in a Java application or applet while it is running.

    All Developer Kit for Linux tools do not use the JIT by default. You cannot enable the JIT.


    Configuring the Developer Kit for Linux

    After you install the Developer Kit for Linux, edit your shell script and add the directory where you installed the Developer Kit to your PATH statement. For more information about the PATH statement, see PATH considerations.


    Installing additional fonts

    The Developer Kit For Linux can display all Unicode characters, but most versions of Linux install only the fonts needed to show your language. You can download fonts from IBM that let you to see the complete Unicode character set. These fonts are not included in the Runtime Environment for Linux package because they are large and not needed by all users. IBM supplies two Unicode fonts, and each of them is customized by country. Users in China and Korea should use the country-specific versions, and all others should use the Japanese version of these fonts.

    If you did not download fonts, you can get them from the DeveloperWorks Web site at http://www.ibm.com/developer/java/ associated with the IBM Developer Kit for Linux(R), Java(TM) 2 Technology Edition, Version 1.2.2. Descriptions of the fonts are provided to help you decide which fonts to download.

    To install a font, put the file in the /opt/IBMJava2-122/jre/lib/fonts directory.

    If you download fonts in parts, you must first put the fonts back together into one file. To put the file back together, be sure it is in the /opt/IBMJava2-122/jre/lib/fonts directory and use the cat command.

    For example, if you downloaded the Times New Roman WorldType (for Japan and other countries) font in parts, type the following command to put it back together:

        cat tmrmtwt_j.t01 tmrmtwt_j.t02 > tmrmtwt_j.ttf
    

    Uninstalling the Developer Kit for Linux

    The process you use to remove the Developer Kit for Linux depends on whether you installed the installable Red Hat Package Manager (RPM) package or the compressed Tape Archive (TAR) package. See Uninstalling the installable Red Hat Package Manager (RPM) package or Uninstalling the compressed TAR package for instructions.


    Uninstalling the installable Red Hat Package Manager (RPM) package

    To uninstall the Developer Kit for Linux if you installed the installable RPM package:

    1. At a shell script, type the following:
          rpm -qa | grep IBM
      
      The name of the package is displayed.

    2. Use the rpm command, as follows:
          rpm -e pkgname
      
      where pkgname is the name of the package that was displayed.
    3. Modify your shell script. Remove the directory where you installed the Developer Kit from your PATH statement.


    Uninstalling the compressed Tape Archive (TAR) package

    To uninstall the Developer Kit for Linux if you installed the compressed TAR package:

    1. Remove the Developer Kit files from the directory where you installed the Developer Kit.
    2. Modify your shell script. Remove the directory where you installed the Developer Kit from your PATH statement.

    Euro symbol support

    To take advantage of the euro symbol support, the operating system must support the euro symbol. To get support for the euro symbol, you might have to install standard ISO-8859-15 (Latin-9 or Latin-0). For further information, see the HOWTO for your distribution of Linux.

    The following sections give further information on euro symbol support.


    Unicode support

    The Unicode character for the euro is u'20ac'.


    Collation of currency symbols

    Collation of currency symbols traditionally follows the English collation order of the symbol name. For example, cent is followed by dollar. According to this scheme, the euro symbol sorts immediately following the dollar and dong currency symbols and before the French franc.


    Using the Developer Kit

    The Java tools are programs that are run from a shell prompt; they do not have a Graphical User Interface (GUI).

    The following sections give information on using the Developer Kit for Linux.


    PATH considerations

    After installing the Developer Kit for Linux software, you can run a tool by typing its name at a shell prompt with a filename as an argument.

    You can specify the path to a tool by typing the path before the name of the tool each time. For example, if the Developer Kit for Linux software is installed in /opt/IBMJava2-122/bin, you can compile a file named myfile.java by typing the following at a shell prompt:

      /opt/IBMJava2-122/bin/javac myfile.java
    

    To avoid typing the full path each time:


    CLASSPATH considerations

    The CLASSPATH tells the Developer Kit for Linux tools, such as java, javac, and javadoc, where to find the Java class libraries. If you keep the bin and lib directories under the same parent directory level, the executable files can find the classes.

    You need to explicitly set the CLASSPATH only if one of the following applies:

    To display the current value of your CLASSPATH, type the following at a shell prompt:

      echo $CLASSPATH

    If you plan to develop and run applications using different runtime environments, including other versions that you have installed separately, you need to set the CLASSPATH (and PATH) explicitly for each application. If you plan to run multiple applications simultaneously using different runtime environments, be sure each application is run in its own shell.

    If you want to run only one version of Java at a time, you can use a shell script to switch between the different runtime environments.


    Running applets with the Applet Viewer

    With the Applet Viewer, you can run one or more applets that are called by reference in a Web page (HTML file) using the APPLET tag. The Applet Viewer finds the APPLET tags in the HTML file and runs the applets, in separate windows.

    Because the Applet Viewer is for viewing applets, it cannot display an entire Web page that contains numerous HTML tags. It parses only the APPLET tag and no other HTML on the Web page.

    To run an applet with the Applet Viewer, type the following at a shell prompt:

       appletviewer name
    

    where name is one of the following:

    For example, to invoke the Applet Viewer on an HTML file that calls an applet, type the following at a shell prompt:

      appletviewer $HOME/filename.html
    
    where filename is the name of the HTML file.

    For example, http://java.sun.com/applets/NervousText/example1.html is the URL of a Web page that calls an applet. To invoke the Applet Viewer on this Web page, type the following at a shell prompt:

      appletviewer http://java.sun.com/applets/NervousText/example1.html
    

    Debugging applets with the Applet Viewer

    You can debug applets using the -debug option of Applet Viewer. When debugging applets, it is best to invoke Applet Viewer from the directory that contains the HTML file that calls the applet. For example:

         cd demo/TicTacToe
         ../../bin/appletviewer -debug example1.html
    

    You might find documentation on the debugger and its API at the following Sun Web site (see http://java.sun.com for any legal statements regarding this information):


    Obtaining the IBM build and version number

    To obtain the IBM build and version number, type the following at a shell prompt:


    Debugging Java applications

    To debug Java programs, you can use the Java Debugger (JDB) application. This debugger communicates with the Java Platform Debugger Architecture (JPDA) provided by the Developer Kit for Linux. For native JNI binary programs, you can still use gdb for debugging.

    Java Platform Debugger Architecture (JPDA)

    The JPDA classes are included in the tools.jar file, which must be included in the CLASSPATH when running Java programs that use the JPDA (for example, JDB). Only socket communication is supported on Linux.

    Java Debugger (JDB)

    A new JDB application is included in the Developer Kit for Linux. The JDB application runs the class com.sun.tools.example.debug.tty.TTY. The Java Virtual Machine Debugging Interface (JVMDI) is now fully supported. The jdb tool included in earlier versions is now included as oldjdb.

    The new JDB application uses the JPDA and enables the jdb example tool to attach to a listening Virtual Machine (VM) or to start a new debug session. It is invoked by the jdb command and can be used in the same way as the oldjdb.

    You can use the JDB application to debug remote Java applications, including Java applications running on remote machines over a TCP/IP link. To debug a remote Java program, start the java program as follows:

    java -Xdebug -Xnoagent -Xrunjdwp:transport=dt_socket,server=y,suspend=y
         -Djava.compiler=NONE <other args> <myapp> <myapp class args>
    

    The port on which the JPDA is listening is displayed. At the remote debugging machine, type the following:

    jdb -attach <machine name or ip address>:<port>
    

    When you launch a debug session using the dt_socket transport, be sure that the specified ports are actually free to use.


    Switching the input method in DBCS languages

    On double-byte character set (DBCS) systems, if you want to switch the input method, you must set an environment variable that represents the keycode you use for switching. Optionally, you can set another environment variable that represents the modifiers of the keycode.

    To specify the keycode to use for switching, set the IBMJAVA_INPUTMETHOD_SWITCHKEY environment variable to a keycode definition in the java.awt.event.KeyEvent class, for example, VK_F4.

    Optionally, specify modifiers of the keycode. To specify modifiers of the keycode, set the IBMJAVA_INPUTMETHOD_SWITCHKEY_MODIFIERS environment variable to any combination of the following three mask definitions in the java.awt.event.InputEvent class:

    Separate the masks by commas.

    For example, you might set the IBMJAVA_INPUTMETHOD_SWITCHKEY_MODIFIERS environment variable to ALT_MASK, CTRL_MASK.

    During Java initialization, the two environment variables are stored. To be sure you have set the environment variables correctly, press a key and check it with the key combination you specified. If it matches, a Java pop-up menu with selectable input methods is displayed.


    RMI over IIOP

    Java Remote Method Invocation (RMI) provides a simple mechanism to do distributed Java programming. RMI over IIOP (RMI-IIOP) extends the base Java RMI capabilities to perform communication using the Common Object Request Broker Architecture (CORBA) standard Internet Inter-ORB Protocol (IIOP protocol). This extension enables direct interaction with any other CORBA Object Request Brokers (ORBs), whether they were implemented in Java or another programming language.

    For information about IBM and RMI-IIOP, see the following IBM Web site:

    http://www.ibm.com/java/jdk/rmi-iiop/index.html

    The following documentation is also available:


    Enhanced BigDecimal

    The Runtime Environment includes an enhanced BigDecimal class (com.ibm.math.BigDecimal) for Java programming. It is provided (with its supporting class MathContext) as an alternative to the java.math.BigDecimal class.

    If you are using the java.math.BigDecimal class in a Java program, and you want to access the class, you must change the import statement in your source code as shown:

    Change import java.math.*; to import com.ibm.math.*;

    You do not need to change any other code.

    More information about enhanced BigDecimal can be found at the following Web site:

    http://www.ibm.com/java/jdk/decimal/


    Shipping Java applications

    A Java application, unlike a Java applet, cannot rely on a Web browser for installation and runtime services. When you ship a Java application, your software package probably consists of the following parts:

    To run your application, a user needs the Runtime Environment for Linux. The Developer Kit for Linux software contains a runtime environment. However, you cannot assume that your users have the Developer Kit for Linux software installed.

    Your Developer Kit for Linux software license does not allow you to redistribute the Developer Kit for Linux software files. You should ensure that a licensed version of the Developer Kit for Linux is installed on the target machine.


    Troubleshooting

    If you encounter a problem after you install the Developer Kit for Linux, check the following list:


    Known limitations

    The following sections explain known limitations of the Developer Kit for Linux.


    General Information


    Information for Japanese users


    Service and support for independent software vendors

    If you are entitled to services for the Program code pursuant to the IBM Solutions Developer Program, contact the IBM Solutions Developer Program through your normal method of access or on the Web at http://www.developer.ibm.com.

    If you have purchased a service contract (that is, IBM's Personal Systems Support Line or equivalent service by country), the terms and conditions of that service contract will determine what services, if any, you are entitled to receive with respect to the Program.


    Notices

    This edition applies to the IBM zSeries Developer Kit for Linux, Java 2 Technology Edition, Version 1.2.2 and to all subsequent releases and modifications until otherwise indicated in new editions.

    Copyright International Business Machines Corporation 2000. All rights reserved.

    Note to U.S. Government Users Restricted Rights -- Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp.

    Consult your local IBM representative for information on the products and services currently available in your area. Any reference to an IBM product, program, or service is not intended to state or imply that only that IBM product, program, or service may be used. Any functionally equivalent product, program, or service that does not infringe any IBM intellectual property right may be used instead. However, it is the users responsibility to evaluate and verify the operation of any non-IBM product, program, or service.

    IBM may have patents or pending patent applications covering subject matter in this document. The furnishing of this document does not give you any license to these patents. You can send license inquiries, in writing, to:

    For license inquiries regarding double-byte (DBCS) information, contact the IBM Intellectual Property Department in your country or send inquiries, in writing, to:

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    This information could include technical inaccuracies or typographical errors. Changes are periodically made to the information herein; these changes will be incorporated in new editions of the information. IBM may make improvements and/or changes in the product(s) and/or the program(s) described in this information at any time without notice.

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    Such information may be available, subject to appropriate terms and conditions, including in some cases, payment of a fee.

    The licensed program described in this document and all licensed material available for it are provided by IBM under terms of the IBM Customer Agreement, IBM International License Agreement or any equivalent agreement between us.

    Information concerning non-IBM products was obtained from the suppliers of those products, their published announcements or other publicly available sources. IBM has not tested those products and cannot confirm the accuracy of performance, compatibility or any other claims related to non-IBM products. Questions on the capabilities of non-IBM products should be addressed to the suppliers of those products.


    Trademarks

    The following terms are trademarks of International Business Machines Corporation in the United States, or other countries, or both:

    Java and all Java-based trademarks are trademarks of Sun Microsystems, Inc. in the United States, other countries, or both.

    Microsoft, Windows, Windows NT, and the Windows logo are trademarks of Microsoft Corporation in the United States, other countries, or both.

    ATOK is a trademark of JUSTSYSTEM Corporation.

    Wnn is a trademark of OMRON software.

    Other company, product, and service names may be trademarks or service marks of others.


    Copyright (c) 1997, 2000 Sun Microsystems, Inc.
    901 San Antonio Rd., Palo Alto, CA 94303 USA.
    All rights reserved.

    (c) Copyright IBM Corporation 2000. All rights reserved.