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Proper Format for a Switch/Case in a Class

Good Evening,
I created this method for a class. I used a switch/case to execute depending on the value of expression. I included an if-else method for each case. I do get an error on case 1-> switch rules are a preview feature and are disabled by default. I attempted to add a : after case 1 and case 2but my results reached high numbers for the sets. I changed the : to -> and it worked appropriately. Now I am wondering if this was a proper way to set the case statements or should it be written differently.
private void playGame()
{
double winCheck = Math.random();
switch (matchServer) {
case 1 ->{
if (winCheck <= player1WinProb)
player1GamesWon++;
else
player2GamesWon++;
matchServer = 2;
}
case 2 ->{
if (winCheck <= player2WinProb)
player2GamesWon++;
else
player1GamesWon++;
matchServer = 1;

A correct switch statement must use ':'
Also, 'break' is missing. This to avoid executing next cases.
You can add 'default' that means that case 1 and case 2 were not presented.
switch (matchServer) {
case 1:
if (winCheck <= player1WinProb)
player1GamesWon++;
else
player2GamesWon++;
matchServer = 2;
break;
case 2:
if (winCheck <= player2WinProb)
player2GamesWon++;
else
player1GamesWon++;
matchServer = 1;
break;
default:
//If it was not 1 or 2
//Printing the values can help
}

comparing the value of each round of a for loop?

Is there a way to grab the resulting number from each iteration of this loop and compare it to the next?
This is a Slot Machine Sim in Java,
I'm trying to find a way to see how many of the results match.
so I thought I would capture the number that is resulted from each round of the For loop and compare it to the previous one.
but I have no idea how to write that?
is there a better way to do this?
what I have so far:
for (int count=1; count<= 3 ; ++count)
{
number = slotM.nextInt(6);
switch (number)
{
case 0:
System.out.print("-cherries-");
break;
case 1:
System.out.print("-Oranges-");
break;
case 2:
System.out.print("-Palms-");
break;
case 3:
System.out.print("-Bells-");
break;
case 4:
System.out.print("-Melones-");
break;
default:
System.out.print("-Bars-");
break;
}
System.out.print(number);
}

Yep there are several better ways. If you have a fixed number of options (6 in your case) an enum might be a good option:
enum Picture {
CHERRIES, ORANGES, PALMS, BELLS, MELONS, BARS;
public String getName() {
return "-" + name().substring(0, 1) + name().substring(1).toLowerCase() + "-";
}
That way you can store your numbers as pictures rather than numbers.
Picture pictures[3];
Random random = new Random();
for (int i = 0; i < pictures.length; i++)
picture[i] = Picture.values[random.nextInt(pictures.length)];
To get the printed version:
for (Picture picture: picture)
System.out.print(picture.getName());

You’ll need some kind of storage outside of the loop so that each iteration can reference it.
int[] results Look in to arrays - you can put the results of each round into a part of the array, and look up the value.

You are declaring your count variable in the for loop, just declare outside and make a comparison with it

Switch Statement key event for 1

switch (event.getCode()) {
case UP: Does Something; break;
case RIGHT: Does Something; break;
case DOWN: Does Something; break; break;
case LEFT: Does Something; break; break;
case NUMPAD1: Does Something; break;
This is probably a super simple answer but I just can't find it on the internet. The code works perfectly that's why I haven't shown it but I just want a Case Key for the number 1 not the NUMPAD 1 as shown in the code. 1 as in the key above Q.
Thanks in advance!

These seem to be enum constants from JavaFX's KeyCode.
According to these docs, the enum constant for key 1 is DIGIT1

Just add:
case 1: Does Something;break;

How to stop JOptionPane from choosing last case?

so here is my case to make a long code short.
Let's say, we have a JOptionPane with 3 buttons.
boolean loopGameInterface = true;
while(loopGameInterface){
int chooseGame = JOptionePane........
switch(chooseGame) {
case 0:
case 1:
case 2:
System.exit(0);
}
}
So the problem is, when I click (example) second button, it goes to case 1. That's fine. But when the code inside case 1 is executed, it goes directly to case 2 and exit my program, instead of just looping the gameInterface?

You need to add break; at the end of each case. This is true for all switch statements by the way, not just when you are using a JOptionPane

switch(chooseGame) {
case 0: /* Your code */
break;
case 1: /* Your code */
break;
case 2:
System.exit(0);
default : "Give some default case too"
}

Its because you haven't added the break statement. If you are not adding break all the cases below the case which matches will be executed. For eg:
switch(ch) {
case 1:
/* some code without break */
case 2:
/* some code without break */
case 3:
System.exit(0);
}
In the above example if ch=1 then all case 2 will also be executed and then case 3.
If ch=2 then only case 2 and case 3 will be executed since case 3 is below case 2. So you need to add break after each case.

Variables from switch statement outside

I am writing a program which contains ComboBox where you choose text and this text will be converted to coefficient using switch statment in program. The problem is that I can't use varible outside switch statment. I really appreciate if someone could help.
Code sample:
double Cst1;
String s = Cst.getSelectedItem().toString();
switch (s) {
case "ABC":
Cst1 = -25;
break;
case "CBA":
Cst1 = -10;
break;
case "BCA":
Cst1 = 0;
break;
case "ACB":
Cst1 = 10;
break;
default:
answer.setText("ERROR");
break;
}
double C14 = 9 * Cst1;

If you get an error which says that the variable is not initialized, try this:
double Cst1 = 0.;

If you have a string value that isn't explicitly covered in your switch, Cst1 will never be initialized. For example, the string "AAA" will fall into the default case.
There are two possible fixes:
Initialize Cst1 like
double Cst1 = 0.
Set Cst1 in your default case like
default:
Cst1 = 0.;
// Display your error
break;