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The value of the parameter type maximumSize ensures that a particular Action does not receive a very large file. The allowedType parameter defines the type of files that are accepted.
However, this approach do does not ensure that the uploaded file conforms to the security requirements as interceptor checks can be trivially bypassed. If an attacker uses a proxy tool to change the content type in the raw HTTP request in transit, the framework would not prevent the file's upload.
This code does not appears to violate ERR08-J. Do not catch NullPointerException or any of its ancestors. But it does not violate that rule, because it falls under the exception ERR08-EX2.
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