java: import include/linux everywhere

[nit.git] / lib / java / java.nit

diff --git a/lib/java/java.nit b/lib/java/java.nit
index cf13a15..0b6a652 100644 (file)
--- a/lib/java/java.nit
+++ b/lib/java/java.nit
@@ -27,7 +27,7 @@
 # most of JNI functions. You can use it to further customize the behavior
 # of your code.
 module java is
-       c_compiler_option("-I $(JAVA_HOME)/include/")
+       c_compiler_option "-I $(JAVA_HOME)/include/ -I $(JAVA_HOME)/include/linux/"
        c_linker_option("-L $(JNI_LIB_PATH) -ljvm")
        new_annotation extra_java_files
 end
@@ -178,4 +178,26 @@ redef extern class JavaObject
        private fun pop_from_local_frame_with_env(jni_env: JniEnv): SELF `{
                return (*jni_env)->PopLocalFrame(jni_env, recv);
        `}
+
+       # Is `self` null in Java?
+       #
+       # Since Java type system doesn't have the same `nullable` concept as Nit's,
+       # the two systems are not directly compatible. Any Nit instances of
+       # `JavaObject` may hold a Java null.
+       #
+       # To benefit from the safer type system of Nit, it is recommended to check
+       # the return of all extern methods implemented in Java to ensure the value
+       # is not a Java null. In case it is, you should replace it by a normal Nit
+       # `null`.
+       fun is_java_null: Bool in "Java" `{ return recv == null; `}
+
+       # `JavaString` representation of `self` using Java's `toString`
+       fun to_java_string: JavaString in "Java" `{ return recv.toString(); `}
+
+       # Use Java's `toString` for any `JavaObject`
+       redef fun to_s
+       do
+               if is_java_null then return super
+               return to_java_string.to_s
+       end
 end