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Passing String from one class to another

How can I pass string variable or String object from one class to another?
I've 2 days on this problem.
One class get data from keyboard and second one should print it in console.

Take some help from the below code:-
public class ReadFrom {
private String stringToShow; // String in this class, which other class will read
public void setStringToShow(String stringToShow) {
this.stringToShow = stringToShow;
}
public String getStringToShow() {
return this.stringToShow;
}
}
class ReadIn {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in); // for taking Keyboard input
ReadFrom rf = new ReadFrom();
rf.setStringToShow(sc.nextLine()); // Setting in ReadFrom string
System.out.println(rf.getStringToShow()); // Reading in this class
}
}

There are two ways:
create an instance of your printer class and evoke the method on the printer object:
public class MyPrinter
{
public void printString( String string )
{
System.out.println( string );
}
}
in your main:
MyPrinter myPrinter = new MyPrinter();
myPrinter.printString( input );
or 2. you create a static method in your printer class and evoke it in your main:
public class MyPrinter
{
public static void printStringWithStaticMethod(String string)
{
System.out.println(string);
}
}
in your main:
MyPrinter.printStringWithStaticMethod( input );

Write a method inside your second class with System.out.println(parameter);
Make the method static and then invoke this in first method like
ClassName.methodName(parameter)

Inside class that accepts Scanner input
variableName ClassName = new Classname();
variablename.methodToPrintString(string);
A textbook can always help in this situation.

How can i access an object from another method in java?

I have the object numberlist that i created in create() method and i want to access it so i can use it in the question() method.
Is there another way to do this that I probably missed? Am I messing something up? If not, how should I do this to get the same functionality as below?
private static void create() {
Scanner input = new Scanner(System.in);
int length,offset;
System.out.print("Input the size of the numbers : ");
length = input.nextInt();
System.out.print("Input the Offset : ");
offset = input.nextInt();
NumberList numberlist= new NumberList(length, offset);
}
private static void question(){
Scanner input = new Scanner(System.in);
System.out.print("Please enter a command or type ?: ");
String c = input.nextLine();
if (c.equals("a")){
create();
}else if(c.equals("b")){
numberlist.flip(); \\ error
}else if(c.equals("c")){
numberlist.shuffle(); \\ error
}else if(c.equals("d")){
numberlist.printInfo(); \\ error
}
}

While interesting, both of the answers listed ignored that fact that the questioner is using static methods. Thus, any class or member variable will not be accessible to the method unless they are also declared static, or referenced statically.
This example:
public class MyClass {
public static String xThing;
private static void makeThing() {
String thing = "thing";
xThing = thing;
System.out.println(thing);
}
private static void makeOtherThing() {
String otherThing = "otherThing";
System.out.println(otherThing);
System.out.println(xThing);
}
public static void main(String args[]) {
makeThing();
makeOtherThing();
}
}
Will work, however, it would be better if it was more like this...
public class MyClass {
private String xThing;
public void makeThing() {
String thing = "thing";
xThing = thing;
System.out.println(thing);
}
public void makeOtherThing() {
String otherThing = "otherThing";
System.out.println(otherThing);
System.out.println(xThing);
}
public static void main(String args[]) {
MyClass myObject = new MyClass();
myObject.makeThing();
myObject.makeOtherThing();
}
}

You would have to make it a class variable. Instead of defining and initializing it in the create() function, define it in the class and initialize it in the create() function.
public class SomeClass {
NumberList numberlist; // Definition
....
Then in your create() function just say:
numberlist= new NumberList(length, offset); // Initialization

Declare numberList outside your methods like this:
NumberList numberList;
Then inside create() use this to initialise it:
numberList = new NumberList(length, offset);
This means you can access it from any methods in this class.

How to call a method with parameter from a diffrent class

Possible noob question but I cant get my method with parameters in one class to call in the other ?
FirstClass
public class Firstclass {
public static void main(String[] args) {
Test1 test = new Test1();
test.Passingvalue();
test.myMethod();
}
}
SecondClass
import java.util.Scanner;
public class Test1 {
public void Passingvalue (){
Scanner Scan = new Scanner(System.in);
System.out.println("File Name ? ");
String txtFile = Scan.next();
}
public void myMethod(String txtFile){
System.out.print("Scan this file" + txtFile);
}
}

You can provide the parameters as a comma separated list in the brackets after the method's name:
public static void main(String[] args) {
Test1 test = new Test1();
test.myMethod("my_file.txt");
}

Don't forget to add a parameter like this :
test.myMethod("txtFile");

declare your string txtfile as a public static variable outside the two methods (at the beginning of class test1) .
public class Firstclass {
public static void main(String[] args) {
Test1 test = new Test1();
test.Passingvalue();
test.myMethod();
}
}
import java.util.Scanner;
public class Test1 {
String txtFile;
public void Passingvalue (){
Scanner Scan = new Scanner(System.in);
System.out.println("File Name ? ");
txtFile = Scan.next();
}
public void myMethod(){
System.out.print("Scan this file" + txtFile);
}
}

I think you have a misconception here:
public void Passingvalue (){
Scanner Scan = new Scanner(System.in);
System.out.println("File Name ? ");
String txtFile = Scan.next(); //method scope only
}
Here the local variable txtFile only exists until the method Passingvalue (check naming conventions btw) is finished, i.e. it has method scope. Thus when calling myMethod(String txtFile) the parameter has the same name but is a different reference in a different scope.
So you'd either have to pass the file name to your method as the others already suggested or change the scope of txtFile, e.g. make it an instance variable:
public class Test1 {
private String txtFile; //the scope of this variable is the instance, i.e. it exists as long as the instance of Test1 exists.
public void Passingvalue (){
Scanner Scan = new Scanner(System.in);
System.out.println("File Name ? ");
txtFile = Scan.next();
}
public void myMethod(){
System.out.print("Scan this file" + txtFile);
}
}
Please note that this is just meant to illustrate the immediate problem. There are other issues, e.g. with the general design, which are not addressed. The purpose of your code seems to be learning anyways, so design is not that big an issue for now.
Just as a hint: I'd probably pass the name from outside the method or pass/read it in a constructor.

when you are calling a parameterize method you should have to pass a parameter to calling method other wise jvm will not understand to whom method you are calling becuase on the basis of parameters we can over load the methods .
so the final answer of your question is
public static void main(String[] args) {
Test1 test = new Test1();
test.myMethod("place your file name here");
}

I am having an "Illegal start of expression" error with user imput

I am trying to get user input, however I am getting
illegal start of expression at:
public static String askTheUser() throws IOException
Complete code:
Edit: I have made most of the changes you guys suggested so now I have this:
import java.io.BufferedReader;
public class Driver
{
public static void main(String[]args)
{
Dice dice;
Craps craps;
userResponse = askTheUser();
while(userResponse.equalsIgnoreCase("yes"))
{
craps = new Craps();
while(!craps.gameOver())
{
craps.roll();
//print out results of roll
}
//print out game results: if(craps.gameWon()...
userResponse.askTheUser();
}
}
public static String askTheUser() throws IOException
{
BufferedReader dataIn = new BufferedReader( new InputStreamReader(System.in) );
String data;
System.out.print("Want to play craps? Yes or No");
data = dataIn.readLine();
if(data.equals("y") || data.equals("yes"))
{
return "yes";
}
else
{
return "no";
}
}
}
However I am still getting cannot find symbol at public static String askTheUser() throws IOException. So might I be missing an import that I don't know of?

you declared askTheUser method inside main method. rip it out off the main method.
public static void main(String[]args)
{
//code that goes inside main
}
public static String askTheUser() throws IOException
{
// code that goes in askTheUser
}

and i don't think that keyboard.readline() works?
use:
InputStreamReader converter = new InputStreamReader(System.in);
BufferedReader in = new BufferedReader(converter);
in.readLine(); // Convert to string or int needed!

You can't write method inside method in Java.
But you can have many methods in the same class.
Why? Because of Java specifications.. you are simply not allowed to do so.
Note that you can have an anonymous inner class with methods under another method.

Java: Identifier expected

What's the issue here?
class UserInput {
public void name() {
System.out.println("This is a test.");
}
}
public class MyClass {
UserInput input = new UserInput();
input.name();
}
This complains:
<identifier> expected
input.name();

Put your code in a method.
Try this:
public class MyClass {
public static void main(String[] args) {
UserInput input = new UserInput();
input.name();
}
}
Then "run" the class from your IDE

You can't call methods outside a method. Code like this cannot float around in the class.
You need something like:
public class MyClass {
UserInput input = new UserInput();
public void foo() {
input.name();
}
}
or inside a constructor:
public class MyClass {
UserInput input = new UserInput();
public MyClass() {
input.name();
}
}

input.name() needs to be inside a function; classes contain declarations, not random code.

Try it like this instead, move your myclass items inside a main method:
class UserInput {
public void name() {
System.out.println("This is a test.");
}
}
public class MyClass {
public static void main( String args[] )
{
UserInput input = new UserInput();
input.name();
}
}

I saw this error with code that WAS in a method; However, it was in a try-with-resources block.
The following code is illegal:
try (testResource r = getTestResource();
System.out.println("Hello!");
resource2 = getResource2(r)) { ...
The print statement is what makes this illegal. The 2 lines before and after the print statement are part of the resource initialization section, so they are fine. But no other code can be inside of those parentheses. Read more about "try-with-resources" here: https://docs.oracle.com/javase/tutorial/essential/exceptions/tryResourceClose.html