 <pre><code>String[] arrFUSE={"3", "true", "0", "FUSE"}; String[] arrPLACE={ "2", "true", "7", "PLACE"}; List&lt;List&lt;String&gt;&gt; arrLIST = new ArrayList&lt;List&lt;String&gt;&gt;(); arrLIST.add( Arrays.asList(arrFUSE) ); arrLIST.add( Arrays.asList(arrPLACE) ); </code></pre> <p>Don't use <code>{</code> on the line you create a new instance of the <code>ArrayList</code>. If you do you will be writing your own implementation of <code>ArrayList</code> on the lines below it. In stead you just want to use the standard <code>ArrayList</code> so terminate that line and start a new one.</p> <p>I also changed <code>ArrayList&lt;ArrayList&lt;String&gt;&gt;</code> to <code>List&lt;List&lt;String&gt;&gt;</code> because you want to be able to put any <code>List</code> in there, not just <code>ArrayLists</code>. In fact what <code>Arrays.asList</code> creates is not an <code>ArrayList</code> so it wouldn't fit otherwise.</p>