java-9-modules-example

Goals

This is a simple, modular java 9 application with three modules.

It illustrates concepts described in Praktyczny przykład - trzy moduły blog post (modular application example).

Generates images with specified width, height, file name and type or rectangle generator.

Requirements

Requires java 16 Originally the project was developed on java 9 (hence its gihub name). In the meantime, as new java versions had been arriving, I extended inital simple app and created a sandbox for checking out new features of subsequent Java releases (records, sealed classes, var ect).

Currently it requires Java 16 and should be built with --enable-preview option.

Using Make

make target would generate image in image directory with following scripts in /image/bin folder:

• cli - just prints to stdout a list of generated rectangles
• gcli - generates single image from commandline
• swingcli - shows Swing window
• fxcli - shows javafx window

Fixing launcher scripts

In ordrer to be able to actually run them, I edit the scripts and add --enable-preview to each script's JLINK_VM_OPTIONS , so insted of

#!/bin/sh
JLINK_VM_OPTIONS=
DIR=`dirname $0`
$DIR/java $JLINK_VM_OPTIONS -m client/com.kamilachyla.Main "$@"

the script looks like this:

#!/bin/sh
JLINK_VM_OPTIONS=--enable-preview
DIR=`dirname $0`
$DIR/java $JLINK_VM_OPTIONS -m client/com.kamilachyla.Main "$@"

The command that does the trick is simple loop with a sed call (double $ sign to refer to simple variable, not make variable; see gnu make official docs:

	for name in image/bin/fxcli image/bin/swingcli image/bin/cli image/bin/gcli ; do 
    sed -i 's/\(JLINK_VM_OPTIONS=\)/\1--enable-preview/' $$name; 
  done

Images and screenshots

Resulting images:

Two GUIs: