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How to end do while loop with user input with if statement [duplicate]

This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 3 years ago.
import java.util.Scanner;
public class main {
public static void main(String[] args) {
boolean a = true;
do {
Scanner input = new Scanner(System.in);
System.out.println("Press any on keyboard:");
String keys = input.nextLine();
System.out.println("You pressed:");
System.out.println(keys);
System.out.println("Your hash is:");
String B = "#B";
String hash = B+keys;
System.out.println(hash);
System.out.println("To end loop press f");
//End Loop
Scanner exit = new Scanner(System.in);
String end = exit.nextLine();
if (end=="f") {
a=false;
}
}
while(a);
}
}
I've been using python and I decided to start learning java since android studio requires it. I'm learning how to do loops again. I can't get this to work. I already looked this up I couldn't find it. How would I end this by pressing 'f'? My thought process was that once it was done going though the first lines of the do loop, it would go though the if statement changing the value of a ending the loop.

use break statement under if(){} body. also your == comparison will give false, use str1.equals(str2) for comparison.

Your problem is you are comparing strings with ==.You have to use equals to write correct if statement.
if (end.equals("f")){...}

You could use the below code to check
if (end.equals("f")) { // end == "f" , it check the reference.
a = false;
}

i keep getting the good bye response no matter if i input yes or no, how would i change that so responses are correct [duplicate]

This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 5 years ago.
I keep getting the 'good bye' response no matter what I enter, 'yes' or 'no'. How would I change that so responses are correct.
import java.util.Scanner;
public class SimpleQuiz1 {
public static void main(String[] args){
Scanner userInputScanner = new Scanner (System.in);
System.out.println("Are you ready to take this NBA quiz?");
String answer = userInputScanner.nextLine();
if(
answer == ("yes")){
System.out.println("Then lets get started!!!");
} else{
answer = ("no");
System.out.println("Goodbye, come again soon!");
}
}
}

Use String.equals(Object obj) rather than == as "==" will check for reference equality whereas .equals compares only the content not the reference.
Scanner userInputScanner = new Scanner(System.in);
System.out.println("Are you ready to take this NBA quiz?");
String answer = userInputScanner.nextLine();
if (answer.equals("yes")) {
System.out.println("Then lets get started!!!");
} else {
this should work fine.

Why does it skip the If statement inside the While loop? It prints out "no work", why? [duplicate]

This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 9 years ago.
This is the program
import java.util.Scanner; //imports class
public class blank2 {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
boolean valid = true;
String ans;
ans = in.next(); //answer is a string
If you type in "y", it goes right to the else statement.
while (valid == true)
{
it always skips this statement
if (ans == "y")
{
System.out.println("it works");
valid = false;
{
else
{
System.out.println("no work");
valid = false;
{
}
}
}
It just wont work

if (ans == "y")
Don't compare strings with ==. That compares object references(the same string). Use:
if ("y".equals(answer))
instead. It will compare strings for equality(check if they are identical as opposed to the same one). I do not use answer.equals("y") due to the risk of a null pointer exception if answer was null for any reason.

In strings, don't use the ==, you can use compareTo instead.
if ("y".comprateTo(answer))
With this method you can check if they are the same, or if one is greater than the other.
let us know if you have questions

While loop in Java, string comparison does not work [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
How do I compare strings in Java?
I'm working on a small program that asks for your name using a Scanner. If you enter blankstring, then I would like the console to display a message.
Here's what I tried doing:
import java.util.Scanner;
public class Adventure
{
public static void main(String[] args)
{
Scanner myScan = new Scanner (System.in);
System.out.println("What's your name?");
String name = myScan.nextLine();
while (!(name == "")) //Always returns false.
{
System.out.println("That's not your name. Please try again.");
name = myScan.nextLine();
}
System.out.println("It's a pleasure to meet you, " + name + ".");
}
}
The code never enters the while loop. Why?

Change your condition to:
while(!name.equals("")) {
or as suggested below by m0skit0:
while(!name.isEmpty()) {
See also
why equals() method when we have == operator?

Java input failure [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
How do I compare strings in Java?
What am I doing wrong? After I compile and run the program, I type in my input and no matter what it is, the program always takes it as an incorrect input and says I'm wrong, here:
import java.util.Scanner;
public class mena3 {
public static void main(String[] args) {
Scanner user_input = new Scanner(System.in);
String Capitol;
System.out.print("Enter the capitol of Morocco: ");
Capitol = user_input.next();
if(Capitol == "Rabat") {
System.out.println("Good Job!");
}
else {
System.out.println("That is incorrect");
}
}
}
And after I put in Rabat, it says That is incorrect. If I put in l, it says That is incorrect. Why can't I win?

Don't compare Strings using ==. Use the equals(...) or the equalsIgnoreCase(...) method instead. Understand that == checks if the two objects are the same which is not what you're interested in. The methods on the other hand check if the two Strings have the same characters in the same order, and that's what matters here. So instead of
if (fu == "bar") {
// do something
}
do,
if ("bar".equals(fu)) {
// do something
}
or,
if ("bar".equalsIgnoreCase(fu)) {
// do something
}
Voting to close this question as it's only been asked and answered umpteen million times on this site.

One of the most common mistakes in java. String require a .equals() rather than an ==.
Wrong:
if (str == "foo") {
}
Right:
if ("foo".equals(str)) { // done in this order to avoid NPE
}

Your code is perfect, only your comparison method is wrong. All other languages treats == as comparison operator. But in case of Java it is little bit tricky. Here in Java == is taken as comparison operator for objects, not a string variable.
So, to compare two Strings you have a method called `.equals() which is from String class it self.
hence you need to change your code accordingly,
import java.util.Scanner;
public class mena3
{
public static void main(String[] args)
{
Scanner user_input = new Scanner(System.in);
String Capitol;
System.out.print("Enter the capitol of Morocco: ");
Capitol = user_input.next();
// if(Capitol == "Rabat") // your previous code
if(Capitol .equals ( "Rabat") ) // new updated comparison code
{
System.out.println("Good Job!");
}
else
{
System.out.println("That is incorrect");
}
}
}