what's the right way to write scala.Function1 as a lambda?
<p>I am trying to <code>transform()</code> a <code>Dataset</code> in Java as follows:  </p>

<pre><code>Function1&lt;Dataset&lt;Long&gt;,Dataset&lt;Long&gt;&gt; withDoubled = (Dataset&lt;Long&gt; numbers) -&gt; numbers.withColumn("doubled",numbers.col("id").multiply(2));
spark.range(10).transform(withDoubled).show();  
</code></pre>

<p>however, <code>Function1&lt;&gt;</code> gets flagged as an error saying there's multiple abstract functions to override. How do I write this as a lambda?</p>