NoSuchMethodError on Collections.max?

Hi,

I have a very simple Kotlin program,

import java.util.Collections

fun main(args: Array<String>): Unit {
  val l = arrayListOf(1,3,4,2)
  javaClass<Collections>().getMethods().forEach { println(it) }
  Collections.sort(l)
  println(Collections.max(l))
}


And it’s failing at run time in this way,

/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/bin/java -Didea.launcher.port=7538 "-Didea.launcher.bin.path=/Applications/IntelliJ IDEA 13 CE.app/bin" -Dfile.encoding=UTF-8 -classpath "/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/lib/javafx-doclet.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/lib/tools.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/htmlconverter.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/JObjC.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Users/acolombi/srcs/kotlin/kotlin/libraries/stdlib/target/classes:/Users/acolombi/srcs/kotlin/kotlin/libraries/tools/runtime/target/classes:/Applications/IntelliJ IDEA 13 CE.app/lib/idea_rt.jar" com.intellij.rt.execution.application.AppMain kotlin.math.MathPackage public static java.lang.Object java.util.Collections.min(java.util.Collection,java.util.Comparator) public static java.lang.Object java.util.Collections.min(java.util.Collection) public static java.lang.Object java.util.Collections.max(java.util.Collection) public static java.lang.Object java.util.Collections.max(java.util.Collection,java.util.Comparator) ... ... many other lines omitted for brevity's sake ... Exception in thread "main" java.lang.NoSuchMethodError: java.util.Collections.max(Ljava/util/Collection;)Ljava/lang/Comparable;      at kotlin.math.MathPackage-CollectionsMath-a72c490a.main(CollectionsMath.kt:28)      at kotlin.math.MathPackage.main(Unknown Source)      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)      at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)      at java.lang.reflect.Method.invoke(Method.java:606)      at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)

NoSuchMethodError shouldn't really ever happen for Java SDK API, right?  And, you can see that I've printed the methods on Collections, and max shows up.  The only difference between the NoSuchMethodError and what I printed is that NoSuchMethod error is complaining about a max method that returns a Comparable, whereas Collections.max returns an Object.

Any thoughts?

-Andrew

Obviously, it's a bug: KT-4271. Please report them directly to issue tracker.

I recommend using max() extension function from Kotlin standard library, it’s nicer!