converted the project to maven and spring boot for easier build and run

.gitignore

@@ -0,0 +1,20 @@
+# Maven compiled output
+target/
+
+# IDE specific files
+.idea/         # IntelliJ IDEA files
+*.iml          # IntelliJ IDEA module files
+.project       # Eclipse project files
+.classpath     # Eclipse classpath files
+.settings/     # Eclipse settings folder
+
+# OS generated files
+.DS_Store      # macOS files
+Thumbs.db      # Windows files
+
+# Other temporary/generated files
+*.log
+*.tmp
+*.class
+*.jar
+*.war

README.md

@@ -18,3 +18,14 @@ If you have a simple, beginner-level Java project that you would like to add to
 
 ## License
 This repository is licensed under the MIT License, which means that you can use, modify, and distribute the code for any purpose, commercial or non-commercial, as long as you give credit to the original author.
+
+## How to Run the Project
+first build the project using Maven:
+mvn clean install (to build the project)
+
+then run the project using one of the following commands:
+mvn spring-boot:run (to run the project) 
+or
+java -jar target/everybody-app-0.1.0.jar 
+or
+from your IDE, run the main method from the Application class.

pom.xml

@@ -0,0 +1,46 @@
+<!-- pom.xml -->
+
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>org.everybody</groupId>
+    <artifactId>everybody-app</artifactId>
+    <version>0.1.0</version>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-starter-parent</artifactId>
+        <version>3.2.3</version>
+        <relativePath/> <!-- lookup parent from repository -->
+    </parent>
+
+    <properties>
+        <java.version>17</java.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter</artifactId>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+            </plugin>
+            <plugin>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>${java.version}</source>
+                    <target>${java.version}</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+</project>

src/main/java/org/everybody/Application.java

@@ -0,0 +1,13 @@
+// src/main/java/org/everybody/Application.java
+package org.everybody;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class Application {
+    public static void main(String[] args) {
+        SpringApplication.run(Application.class, args);
+    }
+}
+

Address Book/AddressBook.java → src/main/java/org/everybody/addressbook/AddressBook.java

@@ -1,6 +1,12 @@
+package org.everybody.addressbook;
+
+import org.everybody.addressbook.ContactAddress;
+
 import java.util.ArrayList;
 import java.util.Scanner;
 
+
+
 public class AddressBook {
     static ArrayList<ContactAddress> contacts = new ArrayList<ContactAddress>();
     static Scanner input = new Scanner(System.in);
@@ -99,38 +105,3 @@ public static void deleteContact() {
     }
 }
 
-class ContactAddress {
-    private String name;
-    private String address;
-    private String phone;
-    private String email;
-
-    public ContactAddress(String name, String address, String phone, String email) {
-        this.name = name;
-        this.address = address;
-        this.phone = phone;
-        this.email = email;
-    }
-
-    public String getName() {
-        return name;
-    }
-
-    public String getAddress() {
-        return address;
-    }
-
-    public String getPhone() {
-        return phone;
-    }
-
-    public String getEmail() {
-        return email;
-    }
-
-    public String toString() {
-        return "Name: " + name + "\nAddress: " + address
-                + "\nPhone: " + phone + "\nEmail: " + email;
-    }
-}
-

src/main/java/org/everybody/addressbook/ContactAddress.java

@@ -0,0 +1,37 @@
+package org.everybody.addressbook;
+
+public class ContactAddress {
+    private String name;
+    private String address;
+    private String phone;
+    private String email;
+
+    public ContactAddress(String name, String address, String phone, String email) {
+        this.name = name;
+        this.address = address;
+        this.phone = phone;
+        this.email = email;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public String getAddress() {
+        return address;
+    }
+
+    public String getPhone() {
+        return phone;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public String toString() {
+        return "Name: " + name + "\nAddress: " + address
+                + "\nPhone: " + phone + "\nEmail: " + email;
+    }
+}
+

Calculator/Calculator.java → src/main/java/org/everybody/calculator/Calculator.java

@@ -1,3 +1,5 @@
+package org.everybody.calculator;
+
 import java.util.Scanner;
 
 public class Calculator {