Installing Qt Jambi

Qt Jambi is available both in prebuilt and source packages for Linux, Mac OS X, and Windows. Java 1.5 or later is required to install Qt Jambi.

The procedure of installing is different depending on whether you have downloaded a source or prebuilt package. This installation guide has separate sections for each approach.

Enjoy !

• Installing from a Prebuilt Package
• Manually Launching Qt Jambi Applications
• Building Qt Jambi from a Source Package
• Configuring the System for Qt Jambi
• Building
• Building and Running the Jambi Generator
• Building C++ libraries and tools
• Generating Ui files
• Building the Java Source Files
• Running Qt Jambi Applications
• Trouble Shooting
• Common Problems
• Load Issues
• Platform Notes

Installing from a Prebuilt Package

After extracting the package, you are ready to run the Launcher, which is an application that runs the examples and demos that come with Qt Jambi.

To run the examples and demo launcher on Windows run the

    qtjambi.exe

executable from the root directory. On Linux and Mac OS X run the

    qtjambi.sh

shell script from the Qt Jambi directory.

Running these files will verify the virtual machine version and set the correct environment for running Qt Jambi applications. If you later have problems running your own applications, you can examine the script, update the class path, and replace your own class with com.trolltech.launcher.Launcher.

Manually Launching Qt Jambi Applications

To manually run Qt Jambi, the CLASSPATH environment variable must include the qtjambi.jar file to get access to the library. To run the examples or launcher, the classpath must also include the Qt Jambi directory.

The QT_PLUGIN_PATH variable must contain the path to the plugins directory in the Qt Jambi directory. Qt Jambi will also search for plugins in .jar files to which the system property com.trolltech.qt.pluginjars contains paths.

Finally, Qt Jambi must be enabled to find the native libraries:

You are then ready to run Qt Jambi applications. For instance, the launcher can be run in the Qt Jambi directory like this on Linux (on Windows, replace the ':' with ';'):

    java -cp qtjambi.jar:. com.trolltech.launcher.Launcher

Note that the -jar option must be given the complete file path to the .jar file.

Building Qt Jambi from a Source Package

This section describes how to build Qt Jambi from source. We first explain how to configure your system, and then we go through the procedure of building Qt Jambi from the command line. Finally, we look at some common installation problems.

Note that a source package requires a Qt installation. On Mac OS X, Qt must be configured without frameworks (by running the configure script with the --no-framework option).

Configuring the System for Qt Jambi

The Jambi source package requires Qt to be installed on the system. The java version must be at least 1.5.

The following table describes the environment variables necessary to install Qt Jambi. We assume that the JAMBI environment variable contains the path to the Qt Jambi directory. The QTDIR variable contains the Qt directory.

Building

We will now go through the procedure of building Qt Jambi step-by-step from the command line. We give shell transcripts for all commands necessary to successfully set up a working Qt Jambi environment. The transcripts are given from a Linux shell, but are essentially equal on all platforms; we will point out differences as we go along.

Building and Running the Jambi Generator

The Jambi Generator generates java source files that wrap the Qt C++ libraries. In order to build Jambi itself, we need the generator. So go into the directory in which it lives:

    cd $JAMBI/generator

Then run qmake and the make tool on your system (On windows the tool is usually gmake or nmake):

    qmake
    make

Then run the generator. Default settings are fine, so no command line arguments are necessary:

On Linux:

    ./generator

On Windows:

    release\generator

The generator will give several warnings while running. This is normal and does not present a problem.

Building C++ libraries and tools

Go back to the JAMBI directory and run qmake to generate the necessary make file. Finally, build with make:

    cd ..
    qmake -r
    make

Generating Ui files

We now need to build the Ui files, i.e., create java files from UI created with the Qt Designer:

    ./bin/juic -cp .

Building the Java Source Files

The generator and juic have now created the Java source files for Qt Jambi. These are all listed in the file java_files. The Java compiler javac can take this file as an argument and will then compile all sources.

    javac @java_files

Note that on some systems it might be necessary to invoke javac with the VM option -J-mx1024m to prevent the VM from running out of heap space; you may need to choose a different heap size than 1024.

Running Qt Jambi Applications

After building Jambi, you should add the JAMBI directory to the class path. Then Qt Jambi applications can be run, for instance the Launcher:

    java com.trolltech.launcher.Launcher

If Qt was built with debugging turned on, you need to use the Qt Jambi debug libraries. You specify this with the com.trolltech.qt.debug system property.

Note that on Mac OS X, the VM must be invoked with the -XstartOnFirstThread option.

Trouble Shooting

If you have trouble compiling and running Qt Jambi, we present problems that are commonly encountered in a table. This should be sufficient to solve most problems; failing that, try asking someone. The Jambi FAQ is a good place to start. In the Jambi Mailing List, active Jambi users and the Jambi development team can be helpful with installation problems; please run Qt Jambi with the com.trolltech.qt.verbose-loading system property and give stack traces if Qt Jambi fails to load native libraries.

Common Problems

In this section, we have tried to gather common problems encountered while building Qt Jambi. They are listed in a table with columns for the problem description and solution.

Load Issues

If Jambi cannot find the native libraries, you will get java.lang.UnsatisfiedLinkError's or other load issues. The search paths - in the order Jambi searches - for libraries are listed below.

• The com.trolltech.qt.library-path system property, which can be given java as command line argument.
• The classpath (including jar files).
• The subdirectory lib (Mac OS X and Linux) or bin (Windows) under the root of the Jambi package structure (i.e., the Qt Jambi directory).
• The java.library.path system property, which is set to LD_LIBRARY_PATH on Linux, PATH on Windows, and DYLD_LIBRARY_PATH on Mac OS X.

Jambi will tell which libraries fail if you run java with the -Dcom.trolltech.qt.verbose-loading=true command line argument. You can then check if the library is in one of Jambi's search paths. Note that Jambi will report on each attempt to load a library.

Jambi depends on a few common system libraries. Notably, Xinerama on Linux, which may be missing on older systems. Information about such missing libraries are not propagated from the operating system to Jambi; how missing libraries are reported may vary from system to system.

Platform Notes