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in Technique[技术] by (71.8m points)

java - Array initialization syntax when not in a declaration

I can write:

AClass[] array = {object1, object2}

I can also write:

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

but I can't write:

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

Why is this blocked by Java?

I know how to work around it, but from time to time it would be simpler.

For example:

public void selectedPointsToMove(cpVect coord) {

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

This simple question that has been bugging me since I learned how to play with arrays in Java.

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by (71.8m points)

Why is this blocked by Java?

You'd have to ask the Java designers. There might be some subtle grammatical reason for the restriction. Note that some of the array creation / initialization constructs were not in Java 1.0, and (IIRC) were added in Java 1.1.

But "why" is immaterial ... the restriction is there, and you have to live with it.

I know how to work around it, but from time to time it would be simpler.

You can write this:

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

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