title: Find unique value of string array and keep order
body: <p>I have a <code>String[]</code> with values like so:<br/></p>
  
  <pre class="lang-java prettyprint-override"><code>line_str = "1,3,4,3,11,2,2,6,7"
  </code></pre>
  
  <p>I want to find unique value and keep the arrangement of value</p>
  
  <pre class="lang-java prettyprint-override"><code>unique_str="1,3,4,11,2,6,7"
  </code></pre>
  
  <p>I'm using a <code>HashSet</code> but the output is:</p>
  
  <pre><code>[1,6,7,4,11,3,2]
  </code></pre>
  
  <p>Here is my code:</p>
  
  <pre class="lang-java prettyprint-override"><code>String line_str = "1,3,4,3,11,2,2,6,7";
  String[] str_arr = line_str.split(",");
  Set&lt;String&gt; uniqueValue = new HashSet&lt;&gt;(Arrays.asList(str_arr));
  Toast.makeText(this, uniqueValue.toString(),Toast.LENGTH_LONG).show();
  </code></pre>