JavaCompiler.getTask() has incomplete specification for IllegalArgumentException

FULL PRODUCT VERSION :


A DESCRIPTION OF THE PROBLEM :
The specification of JavaCompiler.getTask() states that IllegalArgumentException is thrown when:

IllegalArgumentException - if any of the given compilation units are of other kind than source

See: http://java.sun.com/javase/6/docs/api/javax/tools/JavaCompiler.html#getTask(java.io.Writer,%20javax.tools.JavaFileManager,%20javax.tools.DiagnosticListener,%20java.lang.Iterable,%20java.lang.Iterable,%20java.lang.Iterable)

However, the following program illustrates that the method may also throw IllegalArgumentException if the options aren't recognized by the compiler:

     1 import javax.tools.*;
     2 import static java.util.Arrays.asList;
     3
     4 public class Bug {
     5 public static void main(String... args) {
     6 JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
     7 compiler.getTask(null, // out
     8 null, // fileManager
     9 null, // diagnosticListner
    10 asList("-illegalOption"),
    11 null, // classes
    12 null); // compilationUnits
    13 }
    14 }

$ java Bug
Exception in thread "main" java.lang.IllegalArgumentException: invalid flag: -illegalOption
        at com.sun.tools.javac.api.JavacTool.processOptions(JavacTool.java:249)
        at com.sun.tools.javac.api.JavacTool.getTask(JavacTool.java:220)
        at com.sun.tools.javac.api.JavacTool.getTask(JavacTool.java:67)
        at Bug.main(Bug.java:7)




REPRODUCIBILITY :
This bug can be reproduced always.