Installing Java Development Kit (JDK)

Java Development Kit (JDK)

The Java Development Kit (JDK) is a crucial component for Java development, including Spring Boot applications. It provides the necessary tools, libraries, and the Java Runtime Environment (JRE) to compile, run, and debug Java code. In this section, we will explore the JDK and learn how to install and configure it for Spring Boot development.

1. JDK Installation:

To get started with the JDK, follow these steps:

Step 1: Check if Java is already installed by opening a terminal or command prompt and running the following command:

java -version

Step 2: If Java is not installed or an older version is detected, you need to download and install the appropriate JDK version. You can choose between the Oracle JDK or open-source alternatives like AdoptOpenJDK.

Step 3: Visit the official Oracle website or the AdoptOpenJDK website and download the JDK distribution suitable for your operating system.

Step 4: Run the installer and follow the installation wizard instructions to complete the installation process.

2. Environment Variable Setup:

Once the JDK is installed, you need to set up the environment variables to ensure proper configuration.

Step 1: Set the `JAVA_HOME` environment variable to point to the JDK installation directory. This variable helps the system locate the JDK when executing Java-related commands.

Step 2: Update the `PATH` environment variable by appending the JDK’s `bin` directory to it. This addition allows the system to locate the Java executable during command-line operations.

3. Verifying JDK Installation:

To verify that the JDK is correctly installed and configured, perform the following checks:

Step 1: Open a terminal or command prompt and run the following commands:

java -version

This command should display the JDK version that you have installed.

Step 2: Run the following command:

javac -version

This command verifies that the Java compiler (`javac`) is also installed and accessible.

4. Sample Java Code:

Let’s write a simple Java program to test our JDK installation. Create a file named `HelloWorld.java` and add the following code:

public class HelloWorld {
public static void main(String[] args) {
System.out.println("Hello, World!");
}
}

Save the file and open a terminal or command prompt. Navigate to the directory where the `HelloWorld.java` file is saved and compile the code using the `javac` command:

javac HelloWorld.java

This command will generate a compiled bytecode file named `HelloWorld.class`. Now, execute the program using the `java` command:

java HelloWorld

The output should display: “Hello, World!”

Congratulations! You have successfully installed the JDK, configured the environment variables, and executed a Java program.

By having the JDK properly installed and configured, you are ready to dive into Spring Boot development. The JDK provides the necessary tools to build, run, and debug your Spring Boot applications with ease. In the following sections, we will explore more advanced topics related to Spring Boot and leverage the power of the JDK in our development journey.