Java software requirements for FGL
In order to use the Java Interface in your application programs, you need the Java software installed and properly configured.
- Install a Java Development Kit on development sites (if you need to compile your own Java classes)
- Install a Java Runtime Environment on production sites (on the server where your programs are running)
Over time, the Java platform has used different versioning systems, to distinguish a "Java developer version", from a "Java product version". For example, the Java developer version (JDK) 1.8 corresponds to the Java product version 8. With recent versions like Java 10, a unique version numbering convention is used.
The Java classes defined by Genero (com.fourjs.fgl.lang.*
) are compiled with
javac -source 1.6 -target 1.6
options. Therefore, the minimum theoretical version
is Java SE 6. However, depending on the platform, the minimum required Java version may be greater
than version 6.
As a general rule, always install the current long-term-support (LTS) Java version available on your platform, with JNI support. For example, Java SE 8 (released in March 2014) and Java SE 11 (released in September 2018) are LTS versions.
For a detailed list of supported JVMs, refer to the Supported platforms and databases document, available on the Products download page of the Four Js Web site.
java --version
In order to execute Java byte code, the Genero runtime system uses the JNI interface. The JVM is loaded as a shared library and its binary format must match the binary format of the Genero runtime system. For example, a 64-bit Genero package requires a 64-bit JVM.
When implementing Java classes for Genero Mobile for Androidâ„¢ (GMA), check the JDK version required by the Android SDK. For more information, see the Android Studio web site.