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POhow to pass a String* scala vararg to a java method using Scala 2.8
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  1. POhow to pass a String* scala vararg to a java method using Scala 2.8
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    copied!<p>I would like to call the following java method from scala:</p> <pre><code>protected final FilterKeyBindingBuilder filter(String urlPattern, String... morePatterns) { return filtersModuleBuilder.filter(Lists.newArrayList(urlPattern, morePatterns)); } </code></pre> <p>my scala caller looks like this</p> <pre><code>def test(url: String, urls: String*) { filter(url, urls: _*).through(classOf[MyTestWhateverFilter]) } </code></pre> <p>this compiles, however, executing the code gives an exception:</p> <pre><code>java.lang.ClassCastException: scala.collection.mutable.WrappedArray$ofRef cannot be cast to [Ljava.lang.String; </code></pre> <p>I also tried this:</p> <pre><code>def test(url: String, urls: String*) { filter(url, urls.map(_.asInstanceOf[java.lang.String]) :_*).through(classOf[MyTestWhateverFilter]) } </code></pre> <p>in this case the exception was:</p> <pre><code>java.lang.ClassCastException: scala.collection.mutable.ArrayBuffer cannot be cast to [Ljava.lang.String; </code></pre> <p>I thought that in 2.8 Array[String] is passed to java as String[] array and no extra unboxing is necessary.</p> <p>Any ideas?</p> <p>Thanks in advance!</p> <p><strong>EDIT:</strong></p> <p>how to replicate it:</p> <pre><code>import com.google.inject.servlet.ServletModule trait ScalaServletModule extends ServletModule{ def test(s: String,strs: String*) = { println(strs.getClass) println(super.filter(s,strs:_*)) } } object Test { def main(args: Array[String]) { val module = new ServletModule with ScalaServletModule module.test("/rest") } } /opt/local/lib/scala28/bin/scala -cp /Users/p.user/Downloads/guice-2.0/guice-2.0.jar:/Users/p.user/Downloads/guice-2.0/guice-servlet-2.0.jar:/Users/p.user/Downloads/guice-2.0/aopalliance.jar:/Users/p.user/Downloads/javax.jar/javax.jar:. Test </code></pre> <p>result:</p> <pre><code>class scala.collection.mutable.WrappedArray$ofRef java.lang.ClassCastException: scala.collection.mutable.WrappedArray$ofRef cannot be cast to [Ljava.lang.String; at ScalaServletModule$class.test(test.scala:6) at Test$$anon$1.test(test.scala:11) at Test$.main(test.scala:12) at Test.main(test.scala) </code></pre>
 

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