Help with java .LowerCase() function

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1

Hello all,

I have an assignment to create a basic SpamBlocker using Java. I have the bulk of it created but came across an issue with the .LowerCase() function. Everything compiles correctly but the output is not what I expect (input: “make money fast” is different from “Make Money Fast” but I 'd like them to be the same). Here is my code: It relies on another piece of code called IO to compile correctly but I only need help with the .Lowercase() function. Thanks in advance.

public class SpamBlocker
{
public static void main(String[] args)
{
System.out.print("Enter the subject line of the e-mail: ");
String subject = IO.readString();
System.out.println("got user input, subject = " + subject);

    subject.toLowerCase();
    System.out.println("converted to lowercase, subject = " + subject);

    boolean isSpam = false;
    int makeIndex = subject.indexOf("make");
    System.out.println("makeIndex = " + makeIndex);
    int moneyIndex = subject.indexOf("money");
    System.out.println("moneyIndex = " + moneyIndex);
    int fastIndex = subject.indexOf("fast");
    System.out.println("fastIndex = " + fastIndex);

    if (makeIndex != -1  &&  moneyIndex != -1  &&  fastIndex != -1) {
        System.out.println("setting isSpam to true, " +
                           "makeIndex = " + makeIndex +
                           "moneyIndex = " + moneyIndex +
                           "fastIndex = " + fastIndex);
        isSpam = true;
    }
    System.out.println("after if statement, isSpam = " + isSpam + ", subject = " + subject);

    if (isSpam) {
        System.out.println("identified spam, isSpam = " + isSpam + ", subject = " + subject);
        IO.outputStringAnswer("Message is spam.");
    } else {
        System.out.println("identified non-spam, isSpam = " + isSpam + ", subject = " + subject);
        
    IO.outputStringAnswer("Message is legitimate.");
    }
}

}