title: java regular expression to extract content within square brackets
body: <p>input line is below</p>
  
  <pre><code>Item(s): [item1.test],[item2.qa],[item3.production]
  </code></pre>
  
  <p>Can you help me write a Java regular expression to extract</p>
  
  <pre><code>item1.test,item2.qa,item3.production
  </code></pre>
  
  <p>from above input line?</p>