The line import java.util.Scanner;
in Java is used to bring the Scanner
class from the java.util
package into your Java program. Here’s a breakdown of its components:
import: This keyword is used in Java to include other classes or entire packages in your current Java file. Importing allows you to use the classes and interfaces defined in those packages without having to use their fully qualified names.
java.util: This is the package name. The
java.util
package contains utility classes that are part of the Java Standard Library. It includes classes for data structures (likeArrayList
,HashMap
), date and time manipulation, random number generation, and more.Scanner: This is the class that is being imported. The
Scanner
class is a part of thejava.util
package and is used for obtaining input from various sources, including user input from the keyboard, files, and streams. It provides methods to read different types of data, such as strings, integers, and doubles.
Example Usage
Here’s an example of how you might use the Scanner
class in a simple Java program to read user input from the console:
“`java
import java.util.Scanner; // Import the Scanner class
public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in); // Create a Scanner object
System.out.print("Enter your name: ");
String name = scanner.nextLine(); // Read a line of text input from the user
System.out.println("Hello, " + name + "!"); // Output a greeting
scanner.close(); // Close the scanner to free up resources
}
}
“`
Key Points:
- The
Scanner
class is essential for reading input in console-based Java applications. - Always remember to close the
Scanner
object usingscanner.close()
to prevent resource leaks. - The
Scanner
class provides multiple methods to read different types of input, such asnextInt()
,nextDouble()
,nextLine()
, etc.
In summary, import java.util.Scanner;
allows your Java program to use the Scanner
class for handling input, making it easier to interact with users or read data from files.