Here is a map of what J2ObjC translates from Java to Objective-C:

</table>
JavaObjective-C
packages[[class naming|Class-Naming]]
classes interfaces
interfacesprotocols plus [[static variables|Static-Variables-and-Constants]]
enum[[enum translation|Enum-Translation]]
annotationsclass instances returned by reflection
method overloading[[embedded parameter types|Embedded-Method-Parameter-Types]]
static variables and constants[[static variables|Static-Variables-and-Constants]]
inner classesouter classes ([[class naming|Class-Naming]])
anonymous classesouter classes ([[class naming|Class-Naming]])
arrays[[array emulation|Arrays]]
Object.clone, java.lang.Cloneable[[clone support|Object.clone()-support]], NSCopying
synchronized@synchronized
try/catch/finally@try/@catch/@finally
java.lang.ObjectNSObject [[(extended)|Core-Objective-C-Class-Extensions]]
java.lang.StringNSString [[(extended)|Core-Objective-C-Class-Extensions]]
java.lang.NumberNSNumber [[(extended)|Core-Objective-C-Class-Extensions]]
java.lang.ThrowableNSException [[(extended)|Core-Objective-C-Class-Extensions]]
java.lang.Classnative wrapper around Objective-C Class
booleanBOOL
bytechar
charunichar
doubledouble
floatfloat
intint
longlong long int
shortshort int
Java serializationnot implemented
JUnit tests[[JUnit translation|JUnit-Translation]]