[Designer, Java] Several issues in Java reverse engineering

There are several issues in the Java reverse engineering:

• Drag and drop of a Java class into a diagram can potentially freeze your Eclipse, as observed when using Linux
• If the code does not provide the visibility tag (public, private, ...), the default is always private which is not correct for operations in interfaces
• Comments are not taken into account during reverse
• Special characters typed via '\u00xy' in the code are replaced by the special character itself. If represented in opaque expressions or behaviors, these characters break UML/XML serialization (for instance \u0000 and \u001a).
• Bodies of opaque behaviors should not be indented