This question already has answers here:
Close a Scanner linked to System.in
(5 answers)
Scanner is never closed
(4 answers)
Closed 3 months ago.
sc function is never closed. What to do to avoid this error?
I tried to input integer data using scanner function in java, but the sc line is facing some error. Although the code runs properly. But I want to know why it showing error. Thanks in advance.
Related
This question already has answers here:
Resource leak: 'in' is never closed
(14 answers)
Closed 8 months ago.
enter image description here
I just started learning java today. I am now stuck in this user input coding. I have tried many methods but I cannot run this user input code.
As the others already stated closing the scanner is best practice.
If you use Java 8 or higher you can do it the following way:
try(Scanner sc = new Scanner(System.in))
{
String name = sc.nextLine();
System.out.println(name);
}
Besides that your code already works! When you run the program it's waiting for input, so you need to write some text into the console-Window and press enter
This question already has answers here:
How do I declare and initialize an array in Java?
(31 answers)
Closed 2 years ago.
Can i ask whats the meaning of the input "52" on [], because if i delete the 52 the program wont run.
ArrayList<String> playerCard[]= new ArrayList[52];
The 52 tells the compiler how large the array is.
This question already has answers here:
Please explain the usage of Labeled Statements
(3 answers)
Java Label usage [duplicate]
(2 answers)
"loop:" in Java code. What is this, and why does it compile?
(12 answers)
Should I avoid using Java Label Statements?
(12 answers)
Closed 4 years ago.
I've read some tutorials which using this syntax in Java, but I don't know what it's mean?
newNumber:while (1 <= 500) {
// do something
}
I don't understand what newNumber:while mean and I can't find it on oracle documentation.
newValue is label here. You can use it with break and continue statement. It becomes relevant for nesting loops when you want to jump from inside the nested loop.
This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 4 years ago.
I am trying to scan a string and put it in an if like so:
(this is just an example part of the whole program)
Scanner scan=new Scanner();
System.out.print("Enter the word...");
String a=scan.nextLine();
if (a=="Hi")
System.out.println("Hello!")
Else System.exit(0);
So im checking if the user said "Hi" , but it doesnt work like this, I want a way to do it.
I have just started learning java so my questions might seem a little amateur but your answers will help a lot.
Use "Hi".equals(a), == compares identity, not equality.
Also, you should write specifically "Hi".equals(a) and not a.equals("Hi"), because it won't cause a NullPointerException, since a might be null.
This question already has answers here:
Java Scanner with InputStream not working
(2 answers)
Closed 8 years ago.
I am working on an android app so I need to use an InputStream() to read a txt file but I also have several methods that only work with Scanner() so I need a way to convert InputStream() to Scanner().
Thanks in advance.
You can open scanner for this input stream. Like that:
// inputStreamInstance - input stream you want to convert to scanner
Scanner scanner = new Scanner(inputStreamInstance);