Java: Check if a given string contains another string

Java String: Exercise-100 with Solution

Write a Java program to check if a given string contains another string. Returns true or false.

Visual Presentation:

Sample Solution:

Java Code:

// Define a class named Main
public class Main {
    
    // The main method, entry point of the program
    public static void main(String[] args) {
        // Define the main string
        String main_string = "Java is the foundation for virtually every type of " +
            "networked application and is the global standard for developing and " +
            " delivering embedded and mobile applications, games, Web-based content, " +
            " and enterprise software. With more than 9 million developers worldwide," +
            " Java enables you to efficiently develop, deploy and use exciting applications and services.";

        // Display the original string
        System.out.println("Original string:");
        System.out.println(main_string);

        // Define two sub-strings to search within the main string
        String sub_string1 = "million";
        String sub_string2 = "millions";

        // Check if the first sub-string is present in the main string
        boolean result1 = is_present(main_string, sub_string1);
        System.out.println("\nIs '" + sub_string1 + "'" + " present in the said text?");
        System.out.println(result1);

        // Check if the second sub-string is present in the main string
        boolean result2 = is_present(main_string, sub_string2);
        System.out.println("\nIs '" + sub_string2 + "'" + " present in the said text?");
        System.out.println(result2);
    }

    // Method to check if a sub-string is present in the main string
    public static boolean is_present(String main_string, String sub_string) {
        // Check for null or empty strings
        if (main_string == null || sub_string == null || main_string.isEmpty() || sub_string.isEmpty()) {
            return false;
        }

        // Check if the sub-string exists in the main string
        return main_string.indexOf(sub_string) != -1;
    }
}

Sample Output:

Original string:
Java is the foundation for virtually every type of networked application and is the global standard for developing and  delivering embedded and mobile applications, games, Web-based content,  and enterprise software. With more than 9 million developers worldwide, Java enables you to efficiently develop, deploy and use exciting applications and services.

Is 'million' present in the said text?
true

Is 'millions' present in the said text?
false

Flowchart:

Java Code Editor:

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