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Cannot Access Variable inside the for loop

I'm trying to concatenate string values from clientGroupList to make a string variable. I cannot access to the returned variable. I'm working on shareString_8 and shareString_9.
if (uib.getClientProviderType().equals(ParamConstant.CLIENT_TYPE)) {
// ClientUserの場合の処理
//SM4|
String shareString_8 = shareStringList + ":SM" + Constant.SHARE_MODE_CLIENT_GROUP + "|";
for (int idx = 0; idx < clientGroupList.size(); idx++) {
//SM4|SHARE_CLIENT_GROUP
shareString_8 = shareString_8 + clientGroupList.get(idx);
}
return shareString_8;
} else {
// ProviderUserの場合の処理
//SM-1|
String shareString_9 = shareStringList + ":SM" + Constant.SHARE_MODE_PUBLISH + "|";
for (int idx = 0; idx < entityListClientGroup.size(); idx++) {
//SM-1|CLIENT_GROUP_ID
shareString_9 = shareString_9 + clientGroupList.get(idx);
}
return shareString_9;
}
String shareString = providerId + " AND " + "(" + shareString_1 + " OR " + shareString_2 + " OR " + shareString_3
+ " OR " + shareString_4 + " OR " + shareString_5 + " OR " + shareString_6 + " OR " + shareString_7
+ " OR " + shareString_8 + " OR " + shareString_9 + ")";

Java while loop not terminating despite condition being false [duplicate]

This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 2 years ago.
I want to create a game called Crap. The problem that I am facing is that the main while loop does not end despite the condition being set to false (by user inputing "no" when asked if they want to conitnue playing). What is the problem here? Comments are inserted where I think the problem is.
import java.util.Scanner;
public class crap {
public static void main(String[] args) {
System.out.println("You are about to play the game of Crap. Press Enter to continue.");
Scanner enter = new Scanner (System.in);
String hitEnter = enter.nextLine();
Scanner input = new Scanner(System.in);
String proceed = "yes";
// This loop does not exit even if proceed == "no"
while (proceed != "no"){
int playerPoint;
int firstDice = 1 + (int) (Math.random() * 10) % 6;
int secondDice = 1 + (int) (Math.random() * 10) % 6;
int throwSum = firstDice + secondDice;
if (throwSum == 7 || throwSum == 11) {
System.out.println("Congratulations! You win on your first roll! You rolled "
+ firstDice + " and " + secondDice + " for a total of " + throwSum);
}
else if (throwSum == 2 || throwSum == 3 || throwSum == 12) {
System.out.println("Sorry, you crapped out, you lose! You rolled " + firstDice +
" and " + secondDice + " for a total of " + throwSum);
} else {
playerPoint = throwSum;
System.out.println("You rolled " + firstDice + " + " + secondDice + " which is "
+ playerPoint);
System.out.println("Your point is " + playerPoint + " now. Good luck.");
while (throwSum != 7 ) {
firstDice = 1 + (int) (Math.random() * 10) % 6;
secondDice = 1 + (int) (Math.random() * 10) % 6;
throwSum = firstDice + secondDice;
if (throwSum != 7) {
System.out.println("You rolled " + firstDice + " + " + secondDice +
" which is " + throwSum);
if (throwSum == playerPoint) {
System.out.println("Congratulations! You win. You reached your point.");
break;
}
System.out.println("Your point is " + playerPoint + ". Good luck.");
}
else {
System.out.println("You rolled " + firstDice + " + " + secondDice +
" which is " + throwSum);
System.out.println("Sorry, you crapped out, you lose.");
System.out.println("You rolled 7 before reaching your point.");
break;
}
}
}
System.out.println("Do you want to play again? yes/no: ");
// even if user enters "no" the loop does not exit
proceed = input.nextLine();
}
System.out.println("Thanks for playing.");
enter.close();
input.close();
}
}

You are using the wrong operator. != checks if the two objects on left and right side are the the same (e.g. two variables reference the same object in memory).
You must write while (! "no".equals(proceed) ).
I did not write while (! proceed.equals("no") ) on purpose because if the string is null then you would get a NullPointerException.
I am not sure if Scanner.readLine() does ever return a null string, so it may make no difference here. But writing it in the "reverse" way as in my first example is more safely in general.

For a String, the == operator is used to comparing the reference of the given strings, depending on if they are referring to the same objects. When you compare two strings using == operator, it will return true if the string variables are pointing toward the same java object. Otherwise, it will return false .
You have to use .equals(String) to compare Strings, like so:
import java.util.Scanner;
public class crap {
public static void main(String[] args) {
System.out.println("You are about to play the game of Crap. Press Enter to continue.");
Scanner enter = new Scanner (System.in);
String hitEnter = enter.nextLine();
Scanner input = new Scanner(System.in);
String proceed = "yes";
// This loop does not exit even if proceed == "no"
while (!proceed.equals("no")){
int playerPoint;
int firstDice = 1 + (int) (Math.random() * 10) % 6;
int secondDice = 1 + (int) (Math.random() * 10) % 6;
int throwSum = firstDice + secondDice;
if (throwSum == 7 || throwSum == 11) {
System.out.println("Congratulations! You win on your first roll! You rolled "
+ firstDice + " and " + secondDice + " for a total of " + throwSum);
}
else if (throwSum == 2 || throwSum == 3 || throwSum == 12) {
System.out.println("Sorry, you crapped out, you lose! You rolled " + firstDice +
" and " + secondDice + " for a total of " + throwSum);
} else {
playerPoint = throwSum;
System.out.println("You rolled " + firstDice + " + " + secondDice + " which is "
+ playerPoint);
System.out.println("Your point is " + playerPoint + " now. Good luck.");
while (throwSum != 7 ) {
firstDice = 1 + (int) (Math.random() * 10) % 6;
secondDice = 1 + (int) (Math.random() * 10) % 6;
throwSum = firstDice + secondDice;
if (throwSum != 7) {
System.out.println("You rolled " + firstDice + " + " + secondDice +
" which is " + throwSum);
if (throwSum == playerPoint) {
System.out.println("Congratulations! You win. You reached your point.");
break;
}
System.out.println("Your point is " + playerPoint + ". Good luck.");
}
else {
System.out.println("You rolled " + firstDice + " + " + secondDice +
" which is " + throwSum);
System.out.println("Sorry, you crapped out, you lose.");
System.out.println("You rolled 7 before reaching your point.");
break;
}
}
}
System.out.println("Do you want to play again? yes/no: ");
// even if user enters "no" the loop does not exit
proceed = input.nextLine();
}
System.out.println("Thanks for playing.");
enter.close();
input.close();
}
}

How to end the while loop with either player1 or player2 entering "Q"?

I am stuck at a part where in a game, I use while loop and to end the loop and get the results of the game, I want either "player1" or "player2" to enter "Q", and so i tried doing it like this:
if (player1.equals("Q") || player2.equals("Q")){
go = false; //go is a boolean variable
}
This doesn't seem to work as I have to enter "Q" for both player1 and player2 for the game to end, but instead I just want either of them to enter "Q" and the game would stop.
Code:
import java.util.Scanner;
public class Team {
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
System.out.println("Soccer Game Between 2 Teams");
System.out.println("Win is 2 points" + "\n" + "Loss is worth 0 points" + "\n" + "Overtime is worth 1 point");
System.out.println("Type W, O, or L" + "\n" + "Type Q to end the game");
int pointsw = 0;
int pointsl = 0;
int pointso = 0;
int pointsw2 = 0;
int pointsl2 = 0;
int pointso2 = 0;
int totalpoints = 0;
int totalpoints2 = 0;
int counter = 0;
int counter2 = 0;
boolean go = true;
System.out.println("\n" + "Enter team one:");
String phrase = keyboard.next();
System.out.println("\n" + "Enter team two:");
String phrase2 = keyboard.next();
System.out.println();
while (go) {
System.out.println("Enter " + phrase + " Result:");
String team1 = keyboard.next();
System.out.println("Enter " + phrase2 + " Result");
String team2 = keyboard.next();
if (team1.equals("W") || team1.equals("w")) {
pointsw += 2;
} else if (team1.equals("O") || team1.equals("o")) {
pointso += 1;
} else if (team1.equals("L") || team1.equals("l")) {
pointsl += 0;
}
counter++;
if (team2.equals("W") || team2.equals("w")) {
pointsw2 += 2;
} else if (team2.equals("O") || team2.equals("o")) {
pointso2 += 1;
} else if (team2.equals("L") || team2.equals("l")) {
pointsl2 += 0;
}
counter2++;
totalpoints = pointsw + pointso + pointsl;
totalpoints2 = pointsw2 + pointso2 + pointsl2;
if (team1.equals("Q") || team2.equals("Q")) {
go = false;
if (totalpoints > totalpoints2) {
System.out.println(phrase + " wins with " + totalpoints + " points");
System.out.println("It took " + phrase + " " + counter + " rounds to win");
} else if (totalpoints < totalpoints2) {
System.out.println(phrase2 + " wins with " + totalpoints2 + " points");
System.out.println("It took " + phrase2 + " " + counter2 + " rounds to win");
} else if (totalpoints == totalpoints2) {
int totalrounds = counter + counter2;
System.out.println("It is tie game between " + phrase + " and " + phrase2);
System.out.println("The game lasted till " + totalrounds + " rounds");
}
}
}
}
}

You should reorganize your code:
while (true) {
System.out.println("Enter " + phrase + " Result:");
String team1 = keyboard.next().toLowerCase();
if ("q".equals(team1)) {
break;
}
System.out.println("Enter " + phrase2 + " Result");
String team2 = keyboard.next().toLowerCase();
if ("q".equals(team2)) {
break;
}
if (team1.equals("w")) {
pointsw += 2;
} else if (team1.equals("o")) {
pointso += 1;
} else if (team1.equals("l")) {
pointsl += 0;
}
counter++;
if (team2.equals("w")) {
pointsw2 += 2;
} else if (team2.equals("o")) {
pointso2 += 1;
} else if (team2.equals("l")) {
pointsl2 += 0;
}
counter2++;
totalpoints = pointsw + pointso + pointsl;
totalpoints2 = pointsw2 + pointso2 + pointsl2;
} // loop completed
if (totalpoints > totalpoints2) {
System.out.println(phrase + " wins with " + totalpoints + " points");
System.out.println("It took " + phrase + " " + counter + " rounds to win");
} else if (totalpoints < totalpoints2) {
System.out.println(phrase2 + " wins with " + totalpoints2 + " points");
System.out.println("It took " + phrase2 + " " + counter2 + " rounds to win");
} else if (totalpoints == totalpoints2) {
int totalrounds = counter + counter2;
System.out.println("It is tie game between " + phrase + " and " + phrase2);
System.out.println("The game lasted till " + totalrounds + " rounds");
}

I'm not completely sure, but I think the issue is that after player 1 / player 2 says 'Q'
the scanner is still waiting for the next line to read.
String phrase = keyboard.next();
System.out.println("\n"+"Enter team two:");
String phrase2 = keyboard.next();//if player 1 types q this next() method must be resolved before it will continue to the logic
so add an if statement before play 2 goes asking if player 1 typed 'Q' , if so calculate scores and end game, if player 1 did not type 'Q' use else statement to continue on to player 2's turn

Convert numbers in an array to another array

I'm trying to create another array but I want it to be the array double gainT[], which is the temperature in Fahrenheit, converted to Celcius to make another array called double gainTC[]. I am also trying to do the same thing but with the precipitation. I just can't seem to find a way to do it though.
import java.io.IOException;
import java.util.Scanner;
public class AnnualClimate1 {
public static void main(String [] args) throws IOException
{
Scanner in = new Scanner(System.in);
System.out.print("Choose the temperature Scale (F = Fahrenheit, C = Celsius): ");
String tFC = in.nextLine();
System.out.print("Choose the precipitation Scale (I = Inches, C = Centimeters): ");
String pIC = in.nextLine();
System.out.println("");
System.out.println("");
System.out.println(" Climate Data");
System.out.println(" Location: Gainesville, Florida");
System.out.println(" Temperature " + tFC + " Precipitation " + pIC);
System.out.println("=================================================");
double gainT[]={54.3, 57.0, 62.5, 67.6, 74.3, 79.2, 80.9, 80.4, 77.8, 70.1, 62.8, 56.3};
double gainTC[] = {(gainT[] - 32) / 1.8};
double gainP[]={3.5, 3.4, 4.3, 2.9, 3.2, 6.8, 6.1, 6.6, 4.4, 2.5, 2.2, 2.6};
double gainPC[] = {gainP[] / .3937};
if(tFC.equalsIgnoreCase("F") && pIC.equalsIgnoreCase("I")){
System.out.println("Jan. " + gainT[1] + " " + gainP[1]);
System.out.println("Feb. " + gainT[2] + " " + gainP[2]);
System.out.println("Mar. " + gainT[3] + " " + gainP[3]);
System.out.println("Apr. " + gainT[4] + " " + gainP[4]);
System.out.println("May " + gainT[5] + " " + gainP[5]);
System.out.println("Jun. " + gainT[6] + " " + gainP[6]);
System.out.println("Jul. " + gainT[7] + " " + gainP[7]);
System.out.println("Aug. " + gainT[8] + " " + gainP[8]);
System.out.println("Sep. " + gainT[9] + " " + gainP[9]);
System.out.println("Oct. " + gainT[10] + " " + gainP[10]);
System.out.println("Nov. " + gainT[11] + " " + gainP[11]);
System.out.println("Dec. " + gainT[12] + " " + gainP[12]);
}
else if(tFC.equalsIgnoreCase("C") && pIC.equalsIgnoreCase("C")){
System.out.println("Jan. " + gainTC[1] + " " + gainPC[1]);
System.out.println("Feb. " + gainTC[2] + " " + gainPC[2]);
System.out.println("Mar. " + gainTC[3] + " " + gainPC[3]);
System.out.println("Apr. " + gainTC[4] + " " + gainPC[4]);
System.out.println("May " + gainTC[5] + " " + gainPC[5]);
System.out.println("Jun. " + gainTC[6] + " " + gainPC[6]);
System.out.println("Jul. " + gainTC[7] + " " + gainPC[7]);
System.out.println("Aug. " + gainTC[8] + " " + gainPC[8]);
System.out.println("Sep. " + gainTC[9] + " " + gainPC[9]);
System.out.println("Oct. " + gainTC[10] + " " + gainPC[10]);
System.out.println("Nov. " + gainTC[11] + " " + gainPC[11]);
System.out.println("Dec. " + gainTC[12] + " " + gainPC[12]);
}
}
}

Here is an incomplete example so you can fill in the blanks yourself:
double gainT[]={54.3, 57.0, 62.5, 67.6, 74.3, 79.2, 80.9, 80.4, 77.8, 70.1, 62.8, 56.3};
double gainTC[] = new double[gainT.length]; //create array which matches the size of gainT
//array.length is a property value returning the 'size' or length or the array
//Now just iterate through all the gainT[] values you populated above and read each one
for(int i = 0; i < gainT.length; i++){
double math = //use your conversion math here, and store the value
gainTC[i] = math; //assign the results of your math to the same spot in the new array
}
If you'd like more information on Loops and Arrays, check here:
For Loops: https://docs.oracle.com/javase/tutorial/java/nutsandbolts/for.html
Arrays: https://docs.oracle.com/javase/tutorial/java/nutsandbolts/arrays.html

Java - else in the loop statement keeps executing

this has me stumped. Im using a loop to go through an array and then using ifs/else to find whether it meets the criteria. However the else statement keeps being executed even though an if is being executed aswell. Probably something really basic im missing. I need to check in the if statements twice as the user is entering a genre aswell as the item in the array meets that genre too.
cheers
for (int i = 0; i < movies.length; i++)
{
//RentalMovie movie = movies[i];
if(movies[i].getMovieGenre().equalsIgnoreCase("action") && movies[i].getMovieGenre().equalsIgnoreCase(genreID))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else if(movies[i].getMovieGenre().equalsIgnoreCase("childrens") && movies[i].getMovieGenre().equalsIgnoreCase(genreID))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else if (movies[i].getMovieGenre().equalsIgnoreCase("drama") && movies[i].getMovieGenre().equalsIgnoreCase(genreID))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else
{
genreList += "- No rental movies were found for the genre: " + genreID;
}
}

I suspect what you mean is that you have some entries in the array that do match your search condition, and others that don't. For each match, the appropriate if clause is executing, but for each non-match, the else is executing.
Since the action in the else is to add a message indicating that no matches were found, you probably don't want to add that every time a single non-match is found. Rather, you want to do it once, after the loop, if no matches at all were found. This might look like:
String genreList = "";
for (int i = 0; i < movies.length; i++)
{
if(movies[i].getMovieGenre().equalsIgnoreCase("action") && movies[i].getMovieGenre().equalsIgnoreCase(genreID))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else if(movies[i].getMovieGenre().equalsIgnoreCase("childrens") && movies[i].getMovieGenre().equalsIgnoreCase(genreID))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else if (movies[i].getMovieGenre().equalsIgnoreCase("drama") && movies[i].getMovieGenre().equalsIgnoreCase(genreID))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else
{
}
}
if (genreList.equals(""))
{
genreList = "No rental movies were found for the genre: " + genreID;
}
P.S. I don't understand at all why you are checking the genre for each movie against both genreID and a hardcoded value before accepting it. Are there other genres that exist in the list but you don't want a user to be able to search for? That's the only way it seems to make sense, but that doesn't seem like a very sensible requirement.

What is probably happening is that the if statement is not being evaluated correctly. This is what I would try:
for (int i = 0; i < movies.length; i++)
{
//RentalMovie movie = movies[i];
if(movies[i].getMovieGenre().equalsIgnoreCase("action") && movies[i].getMovieGenreID().equalsIgnoreCase(genreID))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else if(movies[i].getMovieGenre().equalsIgnoreCase("childrens") && movies[i].getMovieGenreID().equalsIgnoreCase(genreID))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else if (movies[i].getMovieGenre().equalsIgnoreCase("drama") && movies[i].getMovieGenreID().equalsIgnoreCase(genreID))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else
{
genreList += "- No rental movies were found for the genre: " + genreID;
}
}
The other thing I would try is to get rid of some of the code, ie:
for (int i = 0; i < movies.length; i++)
{
//RentalMovie movie = movies[i];
if(movies[i].getMovieGenre().equalsIgnoreCase("action"))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else if(movies[i].getMovieGenre().equalsIgnoreCase("childrens"))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else if (movies[i].getMovieGenre().equalsIgnoreCase("drama"))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else
{
genreList += "- No rental movies were found for the genres action, childrens, or drama -";
}
}
The third thing I would suggest would be to try this:
for (int i = 0; i < movies.length; i++)
{
//RentalMovie movie = movies[i];
if(movies[i].getMovieGenre().equalsIgnoreCase("action") || movies[i].getMovieGenre().equalsIgnoreCase(genreID))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else if(movies[i].getMovieGenre().equalsIgnoreCase("childrens"))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else if (movies[i].getMovieGenre().equalsIgnoreCase("drama"))
{
genreList += movies[i].getMovieID() + " - " + movies[i].getMovieTitle() + "[" + movies[i].getMediaType() + "]\n";
}
else
{
genreList += "- No rental movies were found for the genre: " + genreID;
}
}

Try stepping through it with a debugger and you can watch the state of the variables as you go.