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PODoes this NullPointerException refer to getFoos returning null or some problem with the cast from a Collection to an ArrayList?
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Id
3535399
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AcceptedAnswerId
3535414
AnswerCount
3
ClosedDate
CommentCount
1
CommunityOwnedDate
CreationDate
2010-08-20T22:52:13.957
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0
LastActivityDate
2010-08-21T00:53:26.263
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425883
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PostTypeId
1
Score
-2
ViewCount
148
LastEditorDisplayName
text
Body
Why does this line cause a <code>NullPointerException</code>: <pre><code> List<Foo> foos = new ArrayList<Foo>(userDetailsService.getFoos(currentUser)); </code></pre> The <code>getFoos</code> method simply returns a <code>Collection</code> of <code>Foo</code>s: <pre><code> public Collection<Foo> getFoos(final String username) </code></pre> I can't tell if the <code>NullPointerException</code> refers to <code>getFoos</code> returning <code>null</code> or some problem with the cast from a <code>Collection</code> to an <code>ArrayList</code>.
Tags
<java><collections><casting><arraylist><nullpointerexception>
Title
Does this NullPointerException refer to getFoos returning null or some problem with the cast from a Collection to an ArrayList?
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 PODoes this NullPointerException refer to getFoos returning null or some problem with the cast from a Collection to an ArrayList?
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1. CO-1 for not posting the stack trace.
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 PODoes this NullPointerException refer to getFoos returning null or some problem with the cast from a Collection to an ArrayList?
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