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Java - IF condition not reading entered String variable value [duplicate]

This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 4 years ago.
import java.util.Scanner;
public class Main
{
public static void main(String[] args)
{
Scanner scan = new Scanner(System.in);
String play = "y";
System.out.print("Enter something: ");
play = scan.next();
System.out.println(play);
if (play == "Y" || play == "y")
{
System.out.println("If test works!!");
}
System.out.println("Did it work???");
}
}
I assume this has something to do with when I press enter, it's storing that as well. I tried changing String play to a char, but then I get errors from Scanner saying it can't change a String to a char.

You should atmost avoid using “==“ when comparing objects especially strings. “==“ checks for object references. Change the comparison to use .equals method and it should work
if(play.equals(“Y”) || play.equals(“y”))
in case if “play” can be null, the below snippet is more safe.
if(“Y”.equals(play) || y.equals(play))

Java: Why does if statement never resolve to true? [duplicate]

This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 6 years ago.
I am trying to make a noughts-and-crosses prototype. The section of code I am struggling with is getting an user input, and if the input is y, it should change the gamestate to 0 which restarts the game. However this doesn't happen. Can anyone explain why?
Scanner s = new Scanner(System.in);
System.out.println("Would you like to play again?");
if (s.next().toLowerCase() == "y") {
System.out.println("Okay");
g.gamestate = 0;
} else {
g.gamestate = 4;
}

Try to use s.next().toLowerCase().equals("y")
Operator "==" comparing the links on your string objects, and method "equals" comparing values.

Yes, as somebody commented the solution is need to use equals() instead of ==.
Scanner s = new Scanner(System.in);
System.out.println("Would you like to play again?");
if (s.next().equalsIgnoreCase("y")) {
System.out.println("Okay");
//g.gamestate = 0;
} else {
System.out.println("No");
// g.gamestate = 4;
}

String comparison doesn't work in while loop [duplicate]

This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 8 years ago.
Noob Java question: Why won't this Do While loop accept the user input? When I use a different variation (such as int for the answer), it works. But when I look for a string, it never accepts the string and escapes the loop.
This works:
int value = 0;
do {
System.out.println("Enter a number: ");
value = scanner.nextInt();
}
while(value != 5);
System.out.println("Do while loop has ended.");
This doesn't work:
String pass;
String word = "word";
do {
System.out.println("Enter password: ");
pass = scanner.nextLine();
}
while(pass != word);
System.out.println("Password accepted.");
Thanks

Change this:
while(pass != word);
to this:
while(!pass.equals(word));
You were comparing the references when you used !=, not the actual content of the strings. Since they did not point to the same String, your loop would always exit on the first run.

"==" compares addresses in memory so if you enter the word which will be the same, the reference you have stored will point to different object.

The if statement is not properly executing after user inputs which if-statement they want to input [duplicate]

This question already has answers here:
How do I compare strings in Java?
(23 answers)
String.equals versus == [duplicate]
(20 answers)
Closed 9 years ago.
package temperatureconversion;
import java.util.Scanner;
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
System.out.println("Please enter Conversion type: Press C for Celsius to Fahrenheit or press F For Fahrenheit to Celsius.");
String Vctype = keyboard.next();
if (Vctype == "f" || Vctype == "F"){
System.out.println("Please enter fahrenheit");
double Vfahrenheit = keyboard.nextInt();
Vfahrenheit = (Vfahrenheit)*(9/5)+(32);
System.out.println(Vfahrenheit);
}
if (Vctype == "c" || Vctype == "C"){
System.out.println("Please enter celcius");
double Vcelcius = keyboard.nextInt();
Vcelcius = (Vcelcius - 32)*(5/9);
System.out.println(Vcelcius) ;
}
}
}
Hello guys I was wondering if anyone could help me with the above code. Basically in the output console in netbeans the program just seems to end after I hit C or F, but instead it should ask for a number then allow a number input, then calculate and finally display the calculation. It doesn't seem to be executing the if statements Where am I going wrong?

You are comparing String with ==. So it doesnt work, you have to use this :
if (Vctype.toLowerCase().equals("f"))
Note also, that using a "toLowerCase" makes the whole string lowercase, so you dont have to have two options for "F" and "f".
If you want, you can use "compareTo"
if (Vctype.toLowerCase().compareTo("f") == 0)

java: simple if condition in while loop does not work [duplicate]

This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 9 years ago.
I'm currently working on a financial planning app for class but I cant get a loop with a condition inside it to work. It just keeps looping despite the condition - it's almost as if the condition is being ignored completely.
Here's my code - please help!
while (true){
Scanner scanVar = new Scanner(System.in);
System.out.println("\nEnter expenditure item: ");
String myString = scanVar.nextLine();
Scanner scanVar2 = new Scanner(System.in);
System.out.println("\nEnter expenditure value: ");
double myDouble = scanVar2.nextDouble();
expenditureMap.put(myString, myDouble);
Scanner scanVar3 = new Scanner(System.in);
System.out.println("\nAnother item? ");
String myString2 = scanVar3.nextLine();
if (myString2 == "yes") {
continue;
}
else {
break;
}
}
Many thanks,
Dylan

You really want to be using mystring2.equals("yes") (or even better, "yes".equals(mystring2) )
The == operator on objects tests for them being the identical instance, not the same string values....
String a = new String("yes");
String b = new String("yes");
a == b => false
a.equals(b) => true

If you are using the == operater it is comparing if the object references match. You should use the equals operator
if (myString2.equals("yes"))

change the condition as follows and then try:
if (myString2.equals("yes")) {

You shall use equals ... check this post
How do I compare strings in Java?
reference comparison means checking if both objects have the same address in memoery
value comparison means checking the value inside the objects