--- a/hotspot/src/share/vm/prims/jni.cpp	Mon Nov 02 12:34:27 2015 +0000
+++ b/hotspot/src/share/vm/prims/jni.cpp	Tue Nov 03 09:41:03 2015 +0100
@@ -2474,12 +2474,18 @@
   typeArrayOop s_value = java_lang_String::value(s);
   if (s_value != NULL) {
     int s_len = java_lang_String::length(s);
-    int s_offset = java_lang_String::offset(s);
+    bool is_latin1 = java_lang_String::is_latin1(s);
     buf = NEW_C_HEAP_ARRAY_RETURN_NULL(jchar, s_len + 1, mtInternal);  // add one for zero termination
     /* JNI Specification states return NULL on OOM */
     if (buf != NULL) {
       if (s_len > 0) {
-        memcpy(buf, s_value->char_at_addr(s_offset), sizeof(jchar)*s_len);
+        if (!is_latin1) {
+          memcpy(buf, s_value->char_at_addr(0), sizeof(jchar)*s_len);
+        } else {
+          for (int i = 0; i < s_len; i++) {
+            buf[i] = ((jchar) s_value->byte_at(i)) & 0xff;
+          }
+        }
       }
       buf[s_len] = 0;
       //%note jni_5
@@ -3118,9 +3124,15 @@
     THROW(vmSymbols::java_lang_StringIndexOutOfBoundsException());
   } else {
     if (len > 0) {
-      int s_offset = java_lang_String::offset(s);
       typeArrayOop s_value = java_lang_String::value(s);
-      memcpy(buf, s_value->char_at_addr(s_offset+start), sizeof(jchar)*len);
+      bool is_latin1 = java_lang_String::is_latin1(s);
+      if (!is_latin1) {
+        memcpy(buf, s_value->char_at_addr(start), sizeof(jchar)*len);
+      } else {
+        for (int i = 0; i < len; i++) {
+          buf[i] = ((jchar) s_value->byte_at(i + start)) & 0xff;
+        }
+      }
     }
   }
 JNI_END
@@ -3186,18 +3198,23 @@
   JNIWrapper("GetStringCritical");
   HOTSPOT_JNI_GETSTRINGCRITICAL_ENTRY(env, string, (uintptr_t *) isCopy);
   GC_locker::lock_critical(thread);
-  if (isCopy != NULL) {
-    *isCopy = JNI_FALSE;
-  }
   oop s = JNIHandles::resolve_non_null(string);
-  int s_len = java_lang_String::length(s);
   typeArrayOop s_value = java_lang_String::value(s);
-  int s_offset = java_lang_String::offset(s);
+  bool is_latin1 = java_lang_String::is_latin1(s);
+  if (isCopy != NULL) {
+    *isCopy = is_latin1 ? JNI_TRUE : JNI_FALSE;
+  }
   const jchar* ret;
-  if (s_len > 0) {
-    ret = s_value->char_at_addr(s_offset);
+  if (!is_latin1) {
+    ret = s_value->char_at_addr(0);
   } else {
-    ret = (jchar*) s_value->base(T_CHAR);
+    // Inflate latin1 encoded string to UTF16
+    int s_len = java_lang_String::length(s);
+    jchar* buf = NEW_C_HEAP_ARRAY(jchar, s_len, mtInternal);
+    for (int i = 0; i < s_len; i++) {
+      buf[i] = ((jchar) s_value->byte_at(i)) & 0xff;
+    }
+    ret = &buf[0];
   }
  HOTSPOT_JNI_GETSTRINGCRITICAL_RETURN((uint16_t *) ret);
   return ret;
@@ -3207,7 +3224,14 @@
 JNI_ENTRY(void, jni_ReleaseStringCritical(JNIEnv *env, jstring str, const jchar *chars))
   JNIWrapper("ReleaseStringCritical");
   HOTSPOT_JNI_RELEASESTRINGCRITICAL_ENTRY(env, str, (uint16_t *) chars);
-  // The str and chars arguments are ignored
+  // The str and chars arguments are ignored for UTF16 strings
+  oop s = JNIHandles::resolve_non_null(str);
+  bool is_latin1 = java_lang_String::is_latin1(s);
+  if (is_latin1) {
+    // For latin1 string, free jchar array allocated by earlier call to GetStringCritical.
+    // This assumes that ReleaseStringCritical bookends GetStringCritical.
+    FREE_C_HEAP_ARRAY(jchar, chars);
+  }
   GC_locker::unlock_critical(thread);
 HOTSPOT_JNI_RELEASESTRINGCRITICAL_RETURN();
 JNI_END