title: Java concurrency - writing to different indexes of the same array
body: <p>Suppose I have an array of data, can 2 threads safely write to different indexes of the same array concurrently?  I'm concerned about write speed, and I want to synchronize the 'get index to write at' bit vs the actual writing.</p>
  
  <p>I am writing code that lets me assume 2 threads will not get the same index.</p>