title: Regex for matching Unicode pattern
body: <p>I am trying to validate a file's content when is uploaded and I am stuck at the Unicode encoding. I am not interested to find Unicode special characters, that are not in the ASCII range. I am trying to find if the content of the file contains at least one Unicode pattern, like \u0046 for example.</p>
  
  <p>For example, I exclude any file that contains the 'script' word, but what if the file contains this word written in Unicode? Sure, Java decodes it into a normal string when it reads the content, but what if I can't rely on this?</p>
  
  <p>So, as far as I have searched on the Internet, I've seen Unicode characters written like \u0046, or like U+0046. Based on this, I have written the following regex:</p>
  
  <pre><code>(\\u|U\+)....
  </code></pre>
  
  <p>This means, \u or U+ followed by four characters. This pattern accomplishes what I desire, but I wonder if there are any other ways to write a Unicode character. It is always \u or U+? Can it be more or less than 4 characters after \u or U+?</p>
  
  <p>Thanks</p>