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POWhy doesn't Scala Source close the underlying InputStream?
 

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    <p>I'm using Scala <code>Source.fromFile</code> however I can't seem to find a nice way of getting it to <code>close</code> the underlying <code>InputStream</code> once the file has been read.</p> <p>Here's my code that will fail with an <code>AssertionError</code> because the file cannot be deleted.</p> <pre><code> def main(args : Array[String]) : Unit = { val myFile = new File("c:/tmp/doodah.txt") var src = Source.fromFile(myFile) src.getLines.foreach(l =&gt; print(l)) val deleted: Boolean = myFile.delete assert (deleted , "File was not deleted - maybe the stream hasn't been closed in Source") } </code></pre> <p>Source has a method called <code>reset</code> however all that this does is recreate the source from the file.</p> <p>Internally <code>Source</code> creates an underlying <code>BufferedSource</code> that has a <code>close</code> method. However this is not exposed from Source.</p> <p>I'd hope that Source would release the file handle once the contents of the file had been read but it doesn't seem to do that.</p> <p>The best workaround I've seen so far is to essentially cast the <code>Source</code> to a <code>BufferedSource</code> and call <code>close</code>.</p> <pre><code>try { src.getLines.foreach(l =&gt; print(l)) } finally src match { case b: scala.io.BufferedSource =&gt; b.close } </code></pre> <p>Alternatively I could create a <code>Source</code> from an <code>InputStream</code> and manage the closing myself.</p> <p>However this seems somewhat <em>dirty</em>. How are you supposed to release the file handle when using <code>Source</code>?</p>
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