putting data from a LinkedBlockingQueue<> to an array not of type object

Question

I am trying to do copy from a LinkedBlockingQueue to a dataStuff[] data array using .toArray() but I am getting an Exception

Exception in thread "main" java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to [LdataStuff;
    at Main.main(Main.java:30)

with the following code

public static BlockingQueue<dataStuff> recurseFragments = new LinkedBlockingQueue<dataStuff>();

    public static void main(String args[]) throws IOException
    {
        dataStuff[] data = (dataStuff[]) recurseFragments.toArray();
    }

I understand that its putting the recurseFragments into an object[] before it spits it into the array but why is it that casting does not work and how can I solve this?

score 2 · Accepted Answer · answered Apr 19 '13 at 19:24

2

Try using the other toArray method

dataStuff[] data = recurseFragments.toArray(new datastuff[0]);

answered Apr 19 '13 at 19:24

Zim-Zam O'Pootertoot

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score 1 · Answer 2 · answered Apr 19 '13 at 19:25

1

Try this:

dataStuff[] data = recurseFragments.toArray(new dataStuff[0])

Using this signature of toArray you can get the correct type of return.

answered Apr 19 '13 at 19:25

Diego D

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Thanks this worked but I accepted the answer that was posted first – JohnM Apr 19 '13 at 19:29

score 1 · Answer 3 · answered Apr 19 '13 at 19:28

1

Because toArray() returns an Object[]

Object[] toArray();

So , you should use toArray(T[] a) instead.

<T> T[] toArray(T[] a);

Use it this way:

recurseFragments.toArray(new datastuff[0]);

answered Apr 19 '13 at 19:28

NINCOMPOOP

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putting data from a LinkedBlockingQueue<> to an array not of type object

3 Answers3