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User Input Java

I am building an application in Java (using NetBeans) that accepts user input through the console and prints out a statement using their name (given in user input). The following is the code:
package amazingpets;
import java.io.Console;
public class AmazingPets {
public static void main(String[] args) {
Console console = System.console();
String firstName = console.readLine("What is your name? ");
console.printf("My name is %s.\n",firstName);
}
}
However I keep getting the following error in the console:
Exception in thread "main" java.lang.NullPointerException
at amazingpets.AmazingPets.main(AmazingPets.java:14)
Java Result: 1
Can anyone please suggest a possible solution?

From the documentation of System#console, it returns:
The system console, if any, otherwise null.
So your code is equivalent to:
String firstName = null.readLine("What is your name? ");
I would suggest you to use Scanner scanner = new Scanner(System.in); instead.

System.console() returns a console if it exists. Java apps may be launched without a console.
Anywhy it seams this is a duplicate of this one (among others):
Why does System.console() return null for a command line app?
Hope it helps

Use Scanner instead of Console
As mentioned in this answer this answer

Isn't line 14 where you create firstName variable? In this case console may be null. Javadoc for Console says
` a unique instance of this class which can be obtained by invoking theSystem.console() method. If no console device is available then an invocation of that method will return null.`

When you run code in an IDE you will usually not have a console object. System.console() will thus return null and console.readLine("What is your name? "); will generate a NullPointerException. You can still read via System.in, so to read a line you can instead use:
Scanner sc = new Scanner(System.in);
String read = sc.nextLine();

NullPointerException in Eclipse but not in command promt

I'm a beginner. Just wondering why this code works perfectly fine in windows command prompt, but I get an:
Exception in thread "main" java.lang.NullPointerException
at Test1.main(Test1.java:13)
error in eclipse. This has happened a lot to me, and it's really stopping me from using eclipse.
Here's the code:
import java.io.Console;
public class Test1 {
public static void main(String[] args) {
Console myConsole = System.console();
for (int a = 0; a < 10; a++){
int a2 = a * a;
myConsole.printf("\n%d squared is: %d.",a,a2); //Problem with this line
}
System.exit(0);
}
}

The javadoc for System.console() states
Returns The system console, if any, otherwise null.
Eclipse must not associate a system console.
Use System.in instead, possibly with a java.util.Scanner for input. And System.out for output.

Simply put, System.console() is returning null in Eclipse, but not when run in a console. This is the documented behaviour:
Returns the unique Console object associated with the current Java virtual machine, if any.
Returns:
The system console, if any, otherwise null.
Why not just use System.out instead? After all, you don't need any of the functionality of Console.

System#console may return null in certain environments. Since youre simply outputting to the console, you don't need to use Console. Formatter can be used instead:
System.out.printf("\n%d squared is: %d.", a, a2);

Why Console in Eclipse or IntelliJ always null? [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
System.Console() returns null
Code:
public class Demo {
public static void main(String[] args){
Console c = System.console();
if (c == null) {
System.err.println("No console.");
System.exit(1);
}else {
System.out.println("Console is.");
System.exit(0);
}
}
}
always No console. Why ? How to fix? Thanks.

You don't have any console associated.
As per javadoc
Returns the unique Console object associated with the current Java
virtual machine, if any, otherwise null
EDIT:
From Console javadoc.
Whether a virtual machine has a console is dependent upon the underlying platform and also upon the manner in which the virtual machine is invoked. If the virtual machine is started from an interactive command line without redirecting the standard input and output streams then its console will exist and will typically be connected to the keyboard and display from which the virtual machine was launched. If the virtual machine is started automatically, for example by a background job scheduler, then it will typically not have a console.

Program works in Eclipse debugger but not anywhere else...?

The following code segment:
private class ConnectionControl implements Runnable
{
public void run()
{
while( true )
{
if( !cnnct.isInMsgEmpty() )
System.out.println( "Incoming message: " + cnnct.getInMsg().getPayloadString() ) ;
}
}
}
Works when I run it in eclipse debugger and place a breakpoint at the System.out line. However, if I run it normally I don't get the "Incoming message..." output.
Any thoughts on why this would be or how even to debug it???
Ahh figured it out... had a deadlock situation going on where two threads were using the same resource. Thanks for your help guys!
Cheers!

There are multiple ways to invoke Java code, depending on where you need it.
What you have shown is not enough to be self-standing, and should cause an error if you try to invoke it as an applet or a java application (java .... ConnectionControl). It may be that Eclipse can invoke a Runnable - I have not seen it though.
Try
making the class public
add a static main method making it a Java application
put a message in the start of the main method so you can see it is invoked

You're already using System.out.println for your program output. Add some sysouts that output where you are in the code and the status of various variables.
I don't know how this is being called but from the code I see your if condition is always evaluating false.

Console class in java Exception in reading password

i am trying to use Console class in java. with this code
import java.io.Console;
public class ConsoleClass {
public static void main(String[] args){
Console c=System.console();
char[] pw;
pw=c.readPassword("%s","pw :");
for(char ch:pw){
c.format("%c",ch);
}
c.format("\n");
MyUtility mu =new MyUtility();
while(true){
String name=c.readLine("%s", "input?: ");
c.format("output: %s \n",mu.doStuff(name));
}
}
}
class MyUtility{
String doStuff(String arg1){
return "result is " +arg1;
}
}
here i am getting NullPointerException when i tried to run in netbeans but i am not getting any Exception when tried to run in cmd with out netbeans IDE.Why?

static Console console()
Returns the unique Console object associated with the current Java virtual machine, if any.
If any.
http://download.oracle.com/javase/6/docs/api/java/lang/System.html

Consoles are typically associated with processes that run independently of frameworks. They are a means of interfacing a process's standard input and output with a shell. If your classes are running as a component of a larger framework, the framework may own the console, and your program might not have a console at all.
There are other conditions and techniques to launch a program without a console. They are typically used when the destruction of the console is guaranteed to occur, but you want the program detached in such a manner that the console's destruction doesn't signal the program's termination.
As such, you cannot guarantee the existence of a console; but, if you are going to run your program in an environment where the console is likely to be present, you should take advantage of it.

System.console() returns a Console instance if a console is associated with the process. - Running under NetBeans you likely don't have an associated console.