diff --git a/dlsmk/src/lib.rs b/dlsmk/src/lib.rs
index b3436bc..14538d9 100644
--- a/dlsmk/src/lib.rs
+++ b/dlsmk/src/lib.rs
@@ -40,7 +40,7 @@
     extern crate jni;
 
     use self::jni::objects::{JClass, JMap, JObject, JString};
-    use self::jni::sys::{jboolean, jint, jlong, JNI_FALSE, JNI_TRUE};
+    use self::jni::sys::{jboolean, jint, jlong, jstring, JNI_FALSE, JNI_TRUE};
     use self::jni::JNIEnv;
     // use super::*;
     use libc;
@@ -140,6 +140,15 @@
         };
     }
 
+    const VERSION: &'static str = env!("CARGO_PKG_VERSION");
+
+    #[no_mangle]
+    pub unsafe extern "C" fn Java_com_supwisdom_dlsmk_DLSMKQrCode_version(env: JNIEnv,
+        _: JClass) -> jstring {
+        let s = env.new_string(String::from(VERSION)).expect("would't get version");
+        s.into_inner()
+    }
+
     #[no_mangle]
     pub unsafe extern "C" fn Java_com_supwisdom_dlsmk_DLSMKQrCode_genTac(
         env: JNIEnv,