How to return an array object without NullPointerException?

Question

Declared:

private Man[] man;

This is the initialization:

Man[] man = new Man[1];

    for (int i = 0; i < 1; i++){
        man[i] = new Man();
            for (int j = 0; j < 3; j++){
                man[i].eatThis(table.foods[table.topFood-1]);
                table.topFood--;
            }
    }

Want to print this:

System.out.println(getMan(0));

which goes to:

public Man getMan(int k){
 return man[k];
}

but I receive NullPointerException. Why? While:

System.out.println(man[0]);

works just fine.

Exception in thread "main" java.lang.NullPointerException
at ManRunning.getMan(ManRunning.java:80)
at ManRunning.newGame(ManRunning.java:133)
at ManRunning.<init>(ManRunning.java:57)
at RunDevilRun.main(RunDevilRun.java:9)

Which variable is not initialized when you get to the line in question? Use a debugger and set a breakpoint nearby, and step through to determine the answer. — Pieter Geerkens
– Pieter Geerkens, Commented Mar 2, 2013 at 4:40
It is hard to give an answer with limited information, can you provide the initialization of the variables used? — RMT
– RMT, Commented Mar 2, 2013 at 4:44

A4L · Accepted Answer · 2013-03-03 03:46:02Z

1

the line (1)

Man[] man = new Man[1];

is hiding the instance variable declared in this line (2)

private Man[] man;

any decent IDE would show a warning for this.

here is how you should initialize the array man in the line (1) declared with line (2)

man = new Man[1];

answered Mar 3, 2013 at 3:46

A4L

17.6k6 gold badges53 silver badges76 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

user207421 · Accepted Answer · 2013-03-03 03:38:51Z

0

Obivously you have two man array variables, one that is initialized and one (a member variable) that isn't.

answered Mar 3, 2013 at 3:38

user207421

312k45 gold badges324 silver badges493 bronze badges

2 Comments

Sam Over a year ago

Could you please show me those mans? One is in method and other one that is initialized as man[i] = new Man()? How can I point to one correct man?

A4L Over a year ago

private Man[] man; is instance variable hidden by local variable Man[] man = new Man[1]; the man you are accessing in getMan(int) is not initialized.

Collectives™ on Stack Overflow

How to return an array object without NullPointerException?

2 Answers 2

Comments

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related