Why Does Java Prevent Uninitialized Array Assignment with Curly Braces?

Uninitialized Array Assignment Syntax

Java allows for concise initialization of arrays within declarations:

AClass[] array = {object1, object2};

However, attempting to assign an uninitialized array with curly braces results in a compiler error:

AClass[] array;
...
array = {object1, object2}; // Error

Reason for Restriction

The specific reason for this restriction is unclear. It may be due to grammatical complexities or the desire to maintain consistency in Java's syntax.

Workaround

Although not as concise, you can initialize an uninitialized array with the new operator and then assign elements explicitly:

AClass[] array;
...
array = new AClass[2];
...
array[0] = object1;
array[1] = object2;

Simplified Example

Using this workaround in the provided code snippet simplifies the array initialization logic:

public void selectedPointsToMove(cpVect coord) {

    if (tab == null) {
        if (arePointsClose(coord, point1, 10))
            tab = new cpVect[]{point1};
        else if (arePointsClose(point2, coord, 10))
            tab = new cpVect[]{point2};
        else
            tab = new cpVect[]{point1, point2};
    }
}

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