finish java project config

java/README.md

@@ -7,18 +7,38 @@ Where install jdk, path to java and javac
 In order to be able to compile and run Java code, you need to install a JDK (Java Development Kit) on your computer.
 A JDK contains a java compiler (`javac`) and a java interpreter (`java` - JRE = Java Runtime Environment).
 
-You can find JDKs at https://openjdk.org/install/ (latest JDK at https://jdk.java.net/).
-If you are using Linux or MacOS, you should install a JDK using your package manager (apt, brew, ...).
+Recommended JDK for windows : https://adoptium.net/temurin/releases/?os=windows&arch=x64&package=jdk.
+
+You can find other JDKs at https://openjdk.org/install/ (latest JDK at https://jdk.java.net/).
+
+**If you are using Linux or MacOS, you should install a JDK using your package manager** (apt, brew, ...).
 
 ### Commands
 
-How this project is configured + the commands
+In this template project, we have chosen the following points :
+
+- use `src/` as the source directory (containing all java files)
+- use `out/` as the output directory (containing all compiled `.class` files)
+- use `src/Main.java` as the main file of the java program
 
-TODO : for Windows in particular, because there is no default Makefile support
+From this configuration, you can use the following commands in the `java/` folder in order to compile and run your program.
+
+```bash
+javac -sourcepath src -d out src/Main.java # Compile
+java -classpath out Main # Run
+```
 
 ### Linux / MacOS - Makefile
 
-TODO : how to use the makefile
+For OS that support the `make` command, the [`Makefile`](./Makefile) defines some commands to compile, run and clean your project.
+You can use it to personalize the project structure.
+
+```bash
+make compile # Compile the project
+make run # Run the project
+make clean # Clear the output directory
+make # Compile, clear terminal and run
+```
 
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