Fix build Java errors caused by UTF-8 characters in source comments

See issue #534
diff --git a/java/CMakeLists.txt b/java/CMakeLists.txt
index 80e0dd2..7d6c70a 100644
--- a/java/CMakeLists.txt
+++ b/java/CMakeLists.txt
@@ -9,7 +9,7 @@
 
 set(DATA_DIR "${CMAKE_INSTALL_PREFIX}/share")
 
-set(DEFAULT_JAVACFLAGS "-source 7 -target 7 -Xlint:all,-serial,-cast,-unchecked,-fallthrough,-dep-ann,-deprecation,-rawtypes")
+set(DEFAULT_JAVACFLAGS "-source 7 -target 7 -encoding UTF-8 -Xlint:all,-serial,-cast,-unchecked,-fallthrough,-dep-ann,-deprecation,-rawtypes")
 set(JAVACFLAGS ${DEFAULT_JAVACFLAGS} CACHE STRING
   "Java compiler flags (Default: ${DEFAULT_JAVACFLAGS})")
 message(STATUS "Java compiler flags = ${JAVACFLAGS}")