Annotations exercise

Installation

Fork this repository.
Clone your fork using IntelliJ.

Configuration

IntelliJ compiles and executes our code from the terminal without our direct intervention. For this exercise we will not use it, because it would hide the warnings that we want to fix. For this exercise we will use the terminal instead.

Compilation

To compile we will use the Java Compiler javac. javac generates the byte code used by the Java Virtual Machine by creating files with the extension .class. Those .class files are the ones executed by the JVM.

You will need to run the following command several times for the exercises in this lesson.

javac -d out/ src/*

In the previous command, the option -d specifies the directory where the .class files are going to be saved, out for this example. src/* tells the compiler to compile all the .java files in the src directory.

Sometimes the compiler produces unrelated error messages when there are existing .class files in the output directory. In order to avoid this issue, it is very recommended to cleanup the out directory before compiling.

rm out/*.class

Execution

In order to execute a Java class you will use the java command as follows.

java -cp out/ Main

The option -cp tells Java where to look for the class to be executed, in this case the out folder, which is where our .class files are. Main is the name of the class with the main method.

Finally