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I can't print out letters in my code? If I remove the 0 from the circle brackets the code won't run

So this question is to let the user enter the product id, the name, how much in stock and how much is bought from the store. Everything in the code works just fine but when I enter the letters for the name, only the first letter shows up.
import java.util.Scanner;
public class ProductStock {
public static void main(String[] args) {
{
Scanner sc = new Scanner(System.in);
int id = sc.nextInt();
char name = sc.next().charAt(0);
int stock = sc.nextInt();
int sold = sc.nextInt();
sc.close();
System.out.print(id + " " + name + " " + stock + " " + sold);
}
}
}

A char in Java represents a single character. To have a sequence of characters, you should use a String. With using charAt(0) in your snippet, you only take the first character of the name you input, but you want to keep the whole String. By calling next() on the scanner, you actually get a String as the return value, so there is nothing more to do.
The fixed example should look like this:
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int id = sc.nextInt();
String name = sc.next();
int stock = sc.nextInt();
int sold = sc.nextInt();
System.out.print(id + " " + name + " " + stock + " " + sold);
sc.close();
}
Just a heads up: once you should be aware that calling close() on a Scanner using System.in, you won't be able to use System.in for the rest of the runtime of your program.

in code char name was storing only the first character and because of char which can only store one character and print that one, so you have to use String for storing and displaying a complete text.
Scanner sc = new Scanner(System.in);
int id = sc.nextInt();
String name = sc.next();
int stock = sc.nextInt();
int sold = sc.nextInt();
sc.close();
System.out.print(id + " " + name + " " + stock + " " + sold);

How to fix nextLine error so that both words are printed? [duplicate]

This question already has answers here:
Scanner is skipping nextLine() after using next() or nextFoo()?
(24 answers)
Closed 3 years ago.
The code below works perfectly when ran, but if you enter two words in the "bands" question you'll only get one printed back.
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
System.out.println("What is your name?");
String name;
name = scan.next();
System.out.println("Hello " + name);
System.out.println("What is your age?");
int years;
years = scan.nextInt();
int ageInMonths;
ageInMonths = years * 12;
System.out.print("Your age is ");
System.out.print(ageInMonths);
System.out.println(" in months");
System.out.println("What are your favorite two bands?");
String bands = scan.next();
System.out.println("I like >>" + bands + "<<too!");
}
}

The method next() from the class Scanner will return only the next token.
As written in the oracle docu:
Finds and returns the next complete token from this scanner. A
complete token is preceded and followed by input that matches the
delimiter pattern. This method may block while waiting for input to
scan, even if a previous invocation of hasNext() returned true.
The default delimiter ist a space, so if your band name will contain more then one word, it will not work.
For reading a whole line of input user nextLine()
If you want to have both band names separatly, call nextLine() twice to get each input separatly:
System.out.println("What are your favorite two bands?");
String band1 = scan.nextLine();
String band2 = scan.nextLine();
System.out.println("I like >>" + band1 + " and " + band2 + "<<too!");
In this case the user has to press 'enter' after each input.
EDIT:
As mentioned in the comment of Elliott Frisch, other readXXX methods will not remove the lineendings from the inputstream.
see:
stackoverflow.com/q/13102045/2970947
You can use nextLine() for every input or remove the lineending after each reading. Sample with your code:
Scanner scan = new Scanner(System.in);
System.out.println("What is your name?");
String name;
name = scan.next();
scan.nextLine();
System.out.println("Hello " + name);
System.out.println("What is your age?");
int years;
years = scan.nextInt();
scan.nextLine();
int ageInMonths;
ageInMonths = years * 12;
System.out.print("Your age is ");
System.out.print(ageInMonths);
System.out.println(" in months");
System.out.println("What are your favorite two bands?");
String bands = scan.nextLine();
System.out.println("I like >>" + bands + "<<too!");
API References:
next()
nextLine()

To get a full string with multiple words (until enter press) you should use scan.nextLine() instead of scan.next() (scan.next() is use to read next word only).
Do not forget to add an extra scan.nextLine() after scan.nextInt()and beforescan.nextLine()` (see it in Java Scanner class reading strings):
public static void main(String... args) {
try (Scanner scan = new Scanner(System.in)) {
System.out.print("What is your name? ");
String name = scan.nextLine();
System.out.println("Hello " + name);
System.out.print("What is your age? ");
int years = scan.nextInt();
int ageInMonths = years * 12;
System.out.println("Your age is " + ageInMonths + " in months");
System.out.print("What are your favorite two bands? ");
scan.nextLine(); // extra one after scan.nextInt() - it retrieves a empty string
String bands = scan.nextLine();
System.out.println("I like >>" + bands + "<< too!");
}
}
Demo, console output:
What is your name? John Doe
Hello John Doe
What is your age? 666
Your age is 7992 in months
What are your favorite two bands? one two three
I like >>one two three<< too!

homework parsing strings: removing comma from string (java zybooks)

I am trying to get the strings to separate, and WITHOUT the comma.
We haven't learned anything like arrays, this is an intro class.
Everything I find on here just keeps giving me errors or does nothing to my code in zybooks.
import java.util.Scanner;
public class ParseStrings {
public static void main(String[] args) {
Scanner scnr = new Scanner(System.in); // Input stream for standard input
Scanner inSS = null; // Input string stream
String lineString = ""; // Holds line of text
String firstWord = ""; // First name
String secondWord = ""; // Last name
boolean inputDone = false; // Flag to indicate next iteration
// Prompt user for input
System.out.println("Enter input string: ");
// Grab data as long as "Exit" is not entered
while (!inputDone) {
// Entire line into lineString
lineString = scnr.nextLine();
inSS = new Scanner(lineString);
firstWord = inSS.next();
lineString.split(",");
// Output parsed values
if (firstWord.equals("q")) {
System.out.println("Enter input string: ");
inputDone = true;
}
//This may be where I am messing up??
else if (lineString.contains(",")) {
secondWord = inSS.next();
System.out.println("First word: " + firstWord);
System.out.println("Second word: " + secondWord);
System.out.println();
} else {
System.out.println("Error: No comma in string");
System.out.println("Enter input string: ");
}
}
return;
}
}
I am messing up somewhere and keep getting different error codes as I keep messing with it...
"Enter input string:
First word: Jill,
Second word: Allen"
When it should be
"Enter input string:
First word: Jill
Second word: Allen"
And then also as the computer enters more data I start getting this message:
"Exception in thread "main" java.util.NoSuchElementException"
at java.util.Scanner.throwFor(Scanner.java:862)
at java.util.Scanner.next(Scanner.java:1371)
at ParseStrings.main(ParseStrings.java:44)"

One of the possibilities (if you didn't learn about arrays) is to use StringBuilder and remove commas or simply loop over input string and if character at let's say index 8 is comma, you do yourString.substring(0,8);, and then print the second word as yourString.substring(10, yourstring.length); I put starting index of 10 in the second substring because you want to skip comma and a space that's separating first and last name. Here is code sample for using nothing but String class, it's methods and for loop:
package com.company;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
System.out.print("Enter first name and last name: ");
String str = in.nextLine();
int indexOfComma = 0;
for (int i = 0; i < str.length(); i++) {
if (str.charAt(i) == ',')
indexOfComma = i;
}
System.out.println("First name is: " + (str.substring(0, indexOfComma)));
System.out.println("Last name is: " + (str.substring(indexOfComma + 2, str.length())));
}
}
Or as I see you tried using split() (but since you said you didn't learn arrays yet I posted solution above), you can do it with .split() like this:
package com.company;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
System.out.print("Enter first name and last name: ");
String[] name = in.nextLine().split(", ");
System.out.println("First name is: " + name[0]);
System.out.println("Last name is: " + name[1]);
}
}
Also, here is an example with StringBuilder class:
package com.company;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
System.out.print("Enter first name and last name: ");
StringBuilder name = new StringBuilder(in.nextLine());
name.deleteCharAt(name.indexOf(","));
System.out.println("Full name is: " + name);
}
}

Your error happens when the Scanner reads all the data, such as calling the nextLine method and there's no line... Or next method when you didn't put a space after the comma
By default, the Scanner uses whitespace as a delimiter. If you want to add a comma delimiter before any whitespace, you can try this
Scanner sc=new Scanner(System.in);
sc.useDelimiter(",?\\s+");
Now, sc.next() will read only Hello from Hello, World, and a second call to it should return World
Or you can use the array you made
String[] words = lineString.split(",");
String first = words[0]:
String second = words[1];

How can I get multiple user inputs and save their value? [duplicate]

How could I read input from the console using the Scanner class? Something like this:
System.out.println("Enter your username: ");
Scanner = input(); // Or something like this, I don't know the code
Basically, all I want is have the scanner read an input for the username, and assign the input to a String variable.

A simple example to illustrate how java.util.Scanner works would be reading a single integer from System.in. It's really quite simple.
Scanner sc = new Scanner(System.in);
int i = sc.nextInt();
To retrieve a username I would probably use sc.nextLine().
System.out.println("Enter your username: ");
Scanner scanner = new Scanner(System.in);
String username = scanner.nextLine();
System.out.println("Your username is " + username);
You could also use next(String pattern) if you want more control over the input, or just validate the username variable.
You'll find more information on their implementation in the API Documentation for java.util.Scanner

Scanner scan = new Scanner(System.in);
String myLine = scan.nextLine();

Reading Data From The Console
BufferedReader is synchronized, so read operations on a BufferedReader can be safely done from multiple threads. The buffer size may be specified, or the default size(8192) may be used. The default is large enough for most purposes.
readLine() « just reads data line by line from the stream or source. A line is considered to be terminated by any one these: \n, \r (or) \r\n
Scanner breaks its input into tokens using a delimiter pattern, which by default matches whitespace(\s) and it is recognised by Character.isWhitespace.
« Until the user enters data, the scanning operation may block, waiting for input.
« Use Scanner(BUFFER_SIZE = 1024) if you want to parse a specific type of token from a stream.
« A scanner however is not thread safe. It has to be externally synchronized.
next() « Finds and returns the next complete token from this scanner.
nextInt() « Scans the next token of the input as an int.
Code
String name = null;
int number;
java.io.BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
name = in.readLine(); // If the user has not entered anything, assume the default value.
number = Integer.parseInt(in.readLine()); // It reads only String,and we need to parse it.
System.out.println("Name " + name + "\t number " + number);
java.util.Scanner sc = new Scanner(System.in).useDelimiter("\\s");
name = sc.next(); // It will not leave until the user enters data.
number = sc.nextInt(); // We can read specific data.
System.out.println("Name " + name + "\t number " + number);
// The Console class is not working in the IDE as expected.
java.io.Console cnsl = System.console();
if (cnsl != null) {
// Read a line from the user input. The cursor blinks after the specified input.
name = cnsl.readLine("Name: ");
System.out.println("Name entered: " + name);
}
Inputs and outputs of Stream
Reader Input: Output:
Yash 777 Line1 = Yash 777
7 Line1 = 7
Scanner Input: Output:
Yash 777 token1 = Yash
token2 = 777

There is problem with the input.nextInt() method - it only reads the int value.
So when reading the next line using input.nextLine() you receive "\n", i.e. the Enter key. So to skip this you have to add the input.nextLine().
Try it like that:
System.out.print("Insert a number: ");
int number = input.nextInt();
input.nextLine(); // This line you have to add (it consumes the \n character)
System.out.print("Text1: ");
String text1 = input.nextLine();
System.out.print("Text2: ");
String text2 = input.nextLine();

There are several ways to get input from the user. Here in this program we will take the Scanner class to achieve the task. This Scanner class comes under java.util, hence the first line of the program is import java.util.Scanner; which allows the user to read values of various types in Java. The import statement line should have to be in the first line the java program, and we proceed further for code.
in.nextInt(); // It just reads the numbers
in.nextLine(); // It get the String which user enters
To access methods in the Scanner class create a new scanner object as "in". Now we use one of its method, that is "next". The "next" method gets the string of text that a user enters on the keyboard.
Here I'm using in.nextLine(); to get the String which the user enters.
import java.util.Scanner;
class GetInputFromUser {
public static void main(String args[]) {
int a;
float b;
String s;
Scanner in = new Scanner(System.in);
System.out.println("Enter a string");
s = in.nextLine();
System.out.println("You entered string " + s);
System.out.println("Enter an integer");
a = in.nextInt();
System.out.println("You entered integer " + a);
System.out.println("Enter a float");
b = in.nextFloat();
System.out.println("You entered float " + b);
}
}

import java.util.Scanner;
public class ScannerDemo {
public static void main(String[] arguments){
Scanner input = new Scanner(System.in);
String username;
double age;
String gender;
String marital_status;
int telephone_number;
// Allows a person to enter his/her name
Scanner one = new Scanner(System.in);
System.out.println("Enter Name:" );
username = one.next();
System.out.println("Name accepted " + username);
// Allows a person to enter his/her age
Scanner two = new Scanner(System.in);
System.out.println("Enter Age:" );
age = two.nextDouble();
System.out.println("Age accepted " + age);
// Allows a person to enter his/her gender
Scanner three = new Scanner(System.in);
System.out.println("Enter Gender:" );
gender = three.next();
System.out.println("Gender accepted " + gender);
// Allows a person to enter his/her marital status
Scanner four = new Scanner(System.in);
System.out.println("Enter Marital status:" );
marital_status = four.next();
System.out.println("Marital status accepted " + marital_status);
// Allows a person to enter his/her telephone number
Scanner five = new Scanner(System.in);
System.out.println("Enter Telephone number:" );
telephone_number = five.nextInt();
System.out.println("Telephone number accepted " + telephone_number);
}
}

You can make a simple program to ask for the user's name and print whatever the reply use inputs.
Or ask the user to enter two numbers and you can add, multiply, subtract, or divide those numbers and print the answers for user inputs just like the behavior of a calculator.
So there you need the Scanner class. You have to import java.util.Scanner;, and in the code you need to use:
Scanner input = new Scanner(System.in);
input is a variable name.
Scanner input = new Scanner(System.in);
System.out.println("Please enter your name: ");
s = input.next(); // Getting a String value
System.out.println("Please enter your age: ");
i = input.nextInt(); // Getting an integer
System.out.println("Please enter your salary: ");
d = input.nextDouble(); // Getting a double
See how this differs: input.next();, i = input.nextInt();, d = input.nextDouble();
According to a String, int and a double varies the same way for the rest. Don't forget the import statement at the top of your code.

A simple example:
import java.util.Scanner;
public class Example
{
public static void main(String[] args)
{
int number1, number2, sum;
Scanner input = new Scanner(System.in);
System.out.println("Enter First multiple");
number1 = input.nextInt();
System.out.println("Enter second multiple");
number2 = input.nextInt();
sum = number1 * number2;
System.out.printf("The product of both number is %d", sum);
}
}

When the user enters his/her username, check for valid entry also.
java.util.Scanner input = new java.util.Scanner(System.in);
String userName;
final int validLength = 6; // This is the valid length of an user name
System.out.print("Please enter the username: ");
userName = input.nextLine();
while(userName.length() < validLength) {
// If the user enters less than validLength characters
// ask for entering again
System.out.println(
"\nUsername needs to be " + validLength + " character long");
System.out.print("\nPlease enter the username again: ");
userName = input.nextLine();
}
System.out.println("Username is: " + userName);

To read input:
Scanner scanner = new Scanner(System.in);
String input = scanner.nextLine();
To read input when you call a method with some arguments/parameters:
if (args.length != 2) {
System.err.println("Utilizare: java Grep <fisier> <cuvant>");
System.exit(1);
}
try {
grep(args[0], args[1]);
} catch (IOException e) {
System.out.println(e.getMessage());
}

import java.util.*;
class Ss
{
int id, salary;
String name;
void Ss(int id, int salary, String name)
{
this.id = id;
this.salary = salary;
this.name = name;
}
void display()
{
System.out.println("The id of employee:" + id);
System.out.println("The name of employye:" + name);
System.out.println("The salary of employee:" + salary);
}
}
class employee
{
public static void main(String args[])
{
Scanner sc = new Scanner(System.in);
Ss s = new Ss(sc.nextInt(), sc.nextInt(), sc.nextLine());
s.display();
}
}

Here is the complete class which performs the required operation:
import java.util.Scanner;
public class App {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
final int valid = 6;
Scanner one = new Scanner(System.in);
System.out.println("Enter your username: ");
String s = one.nextLine();
if (s.length() < valid) {
System.out.println("Enter a valid username");
System.out.println(
"User name must contain " + valid + " characters");
System.out.println("Enter again: ");
s = one.nextLine();
}
System.out.println("Username accepted: " + s);
Scanner two = new Scanner(System.in);
System.out.println("Enter your age: ");
int a = two.nextInt();
System.out.println("Age accepted: " + a);
Scanner three = new Scanner(System.in);
System.out.println("Enter your sex: ");
String sex = three.nextLine();
System.out.println("Sex accepted: " + sex);
}
}

There is a simple way to read from the console.
Please find the below code:
import java.util.Scanner;
public class ScannerDemo {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
// Reading of Integer
int number = sc.nextInt();
// Reading of String
String str = sc.next();
}
}
For a detailed understanding, please refer to the below documents.
Doc
Now let's talk about the detailed understanding of the Scanner class working:
public Scanner(InputStream source) {
this(new InputStreamReader(source), WHITESPACE_PATTERN);
}
This is the constructor for creating the Scanner instance.
Here we are passing the InputStream reference which is nothing but a System.In. Here it opens the InputStream Pipe for console input.
public InputStreamReader(InputStream in) {
super(in);
try {
sd = StreamDecoder.forInputStreamReader(in, this, (String)null); // ## Check lock object
}
catch (UnsupportedEncodingException e) {
// The default encoding should always be available
throw new Error(e);
}
}
By passing the System.in this code will opens the socket for reading from console.

You can flow this code:
Scanner obj= new Scanner(System.in);
String s = obj.nextLine();

You can use the Scanner class in Java
Scanner scan = new Scanner(System.in);
String s = scan.nextLine();
System.out.println("String: " + s);

import java.util.Scanner; // Import the Scanner class
class Main { // Main is the class name
public static void main(String[] args) {
Scanner myObj = new Scanner(System.in); // Create a Scanner object
System.out.println("Enter username");
String userName = myObj.nextLine(); // Read user input
System.out.println("Username is: " + userName); // Output user input
}
}

you have wrote
Scanner = input()
this is wrong method, you have to make an integer or a string, i would like to prefer string, and then give a string any name that can be i that can be n or anything else, remember that you are giving name to username you can also give name username also, and the code is
String username = sc.nextline();
System.our.println("the username is" + username);
I hope you understand now

I am having trouble with this String Parser, how can I approach it?

Create a String variable and assign your full name to the variable.
Using the String's substring method print out your first name, middle name, and last name on three separate lines.
Modify your program so that it creates a "Scanner" object to allow the user to type in any three names and store it in the String variable.
Modify your program so that it will print out the three names on separate lines no matter what three names the user enters (Hint: use the String's indexof method).
So for this problem, I am doing it in Java. Here is what I have so far. Thank you!
package stringparser;
import java.util.Scanner;
public class StringParser
{
public static void main(String[] args)
{
String Name = "Billy Bob Joe";
String first = Name.substring(0,5);
String middle = Name.substring(6,12);
String last = Name.substring(13,16);
System.out.println("First name: " + first);
System.out.println("Middle name: " + middle);
System.out.println("Last name: " + last);
Scanner in = new Scanner(System.in);
System.out.print("Type any 3 names: ");
System.out.print("First name: ");
String a = in.nextLine();
System.out.print("Second name: ");
String b = in.nextLine();
System.out.print("Third name: ");
String c = in.next();
}
}

2 ways I interpret this question.
Use Scanner 3 times
Use indexOf to find the nearest space character of the one console input.
In all, I find it painfully inefficient to use String.indexOf
Quickest way, but not necessarily the best way.
public StringParser () {
Scanner in = new Scanner(System.in);
String name = in.nextLine();
System.out.println(name.replace(" ", "\n")); // replacing all spaces with new line characters
}

This program will split the string with space and print all of them as result. You can edit the for loop condition as per your need. Hope it helps :)
public static void main(String[] args)
{
Scanner in = new Scanner(System.in);
String str = in.nextLine();
String[] names = str.split(" ");
for(int i = 0; i < names.length; i++)
{
System.out.println(names[i]);
}
}