--- a/src/jdk.compiler/share/classes/com/sun/tools/javac/resources/javac.properties	Thu Apr 12 09:23:34 2018 +0200
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/resources/javac.properties	Thu Apr 12 13:55:20 2018 +0100
@@ -252,6 +252,9 @@
 javac.opt.Xlint.desc.varargs=\
     Warn about potentially unsafe vararg methods
 
+javac.opt.Xlint.desc.preview=\
+    Warn about use of preview language features
+
 javac.opt.Xdoclint=\
     Enable recommended checks for problems in javadoc comments
 # L10N: do not localize: all none
@@ -293,6 +296,8 @@
     Search classpath and sourcepath for classes before the bootclasspath instead of after
 javac.opt.prefer=\
     Specify which file to read when both a source file and class file are found for an implicitly compiled class
+javac.opt.preview=\
+    Enable preview language features. To be used in conjunction with either -source or --release.
 javac.opt.AT=\
     Read options and filenames from file
 javac.opt.diags=\
@@ -368,6 +373,11 @@
     target release {0} conflicts with default source release {1}
 javac.warn.profile.target.conflict=\
     profile {0} is not valid for target release {1}
+javac.err.preview.not.latest=\
+    invalid source release {0} with --enable-preview\n\
+    (preview language features are only supported for release {1})
+javac.err.preview.without.source.or.release=\
+    --enable-preview must be used with either -source or --release
 javac.err.file.not.found=\
     file not found: {0}
 javac.err.file.not.directory=\