title: How to Join Multiple Columns in Spark SQL using Java for filtering in DataFrame
body: <ul>
  <li><code>DataFrame a</code> = contains column x,y,z,k</li>
  <li><p><code>DataFrame b</code> = contains column x,y,a</p>
  
  <pre><code>a.join(b,&lt;condition to use in java to use x,y &gt;) ??? 
  </code></pre></li>
  </ul>
  
  <p>I tried using </p>
  
  <pre><code>a.join(b,a.col("x").equalTo(b.col("x")) &amp;&amp; a.col("y").equalTo(b.col("y"),"inner")
  </code></pre>
  
  <p>But Java is throwing error saying <code>&amp;&amp;</code> is not allowed.</p>