CODEWITHSUNDEEP
java
Manipal
Manipal

Reputation: 309

Array of objects initialization

I am creating an array of Objects, is there any way to call constructor of objects from the same line? 

//Creating an array of employees
Employee[] emp=new Employee[10];
//above line creates only references pointing to null, how can i create objects
//by calling constructors in the same line?

Upvotes: 2

Views: 173

Answers (4)

Michael Berry
Michael Berry

Reputation: 72284

Update: This is now possible in a one liner with Java streams:

Employee[] arr = Stream.generate(() -> new Employee())
        .limit(10)
        .toArray(Employee[]::new);

Original answer below, still applies to pre Java 8:

Nope, not from the same line on any sensible level - the convention is to loop through the array and fill it with objects if needed:

for(int i=0 ; i<emp.length ; i++) {
    emp[i] = new Employee();
}

It's actually relatively unusual that you want to fill an array with the same objects as soon as you create it (especially in Java where Lists are more popular) thus no shorthand exists beyond the manual array initialiser approach. If you do find yourself doing this often for whatever reason, you could farm the for loop out to a separate fill() (or similar) method, and thus at least make filling the array in this way a quick one liner.

Upvotes: 6

Sotirios Delimanolis
Sotirios Delimanolis

Reputation: 279940

You can do the completely ridiculous way

Employee[] emp = new Employee[] {new Employee(/* args */), new Employee(/* args */), new Employee(/* args */), ...} ;

But there really is no point. Use a for loop.

Java 8 introduced Arrays.setAll which accepts a generator function that can be used to instantiate and initialize the objects to fill the array.

Arrays.setAll(emp, index -> new Employee(/* args */));

Upvotes: 3

CharlyDelta
CharlyDelta

Reputation: 938

You can either achieve this with a loop:

for(int i = 0; i < emp.length; i++) {
    emp[i] = new Employee();
}

or with a direct initialization like

Employee[] emp = {new Employee(), new Employee(), ...}

I'd prefer the loop...

Upvotes: 1

rgettman
rgettman

Reputation: 178263

Use an array initializer:

Employee[] emp = {new Employee("Joe"), new Employee("John")};

Upvotes: 3

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