Merge pull request #441 from fyrz/RocksJava-ColumnFamilyDescriptor-Alignment

[RocksJava] ColumnFamilyDescriptor alignment with listColumnFamilies

java/RocksDBColumnFamilySample.java

@@ -33,7 +33,8 @@ public class RocksDBColumnFamilySample {
 
       // create column family
       columnFamilyHandle = db.createColumnFamily(
-          new ColumnFamilyDescriptor("new_cf", new ColumnFamilyOptions()));
+          new ColumnFamilyDescriptor("new_cf".getBytes(),
+          new ColumnFamilyOptions()));
       assert(columnFamilyHandle != null);
 
     } finally {
@@ -56,7 +57,7 @@ public class RocksDBColumnFamilySample {
         RocksDB.DEFAULT_COLUMN_FAMILY, new ColumnFamilyOptions()));
     // open the new one, too
     columnFamilyDescriptors.add(new ColumnFamilyDescriptor(
-        "new_cf", new ColumnFamilyOptions()));
+        "new_cf".getBytes(), new ColumnFamilyOptions()));
     List<ColumnFamilyHandle> columnFamilyHandles = new ArrayList<>();
     try {
       db = RocksDB.open(new DBOptions(), db_path,

java/org/rocksdb/ColumnFamilyDescriptor.java

@@ -16,8 +16,22 @@ public class ColumnFamilyDescriptor {
    * options,</p>
    *
    * @param columnFamilyName name of column family.
+   * @deprecated will be removed in RocksDB 3.10.0. Use
+   * {@link #ColumnFamilyDescriptor(byte[])} instead.
    */
+  @Deprecated
   public ColumnFamilyDescriptor(final String columnFamilyName){
+    this(columnFamilyName.getBytes(), new ColumnFamilyOptions());
+  }
+
+  /**
+   * <p>Creates a new Column Family using a name and default
+   * options,</p>
+   *
+   * @param columnFamilyName name of column family.
+   * @since 3.10.0
+   */
+  public ColumnFamilyDescriptor(final byte[] columnFamilyName) {
     this(columnFamilyName, new ColumnFamilyOptions());
   }
 
@@ -28,9 +42,26 @@ public class ColumnFamilyDescriptor {
    * @param columnFamilyName name of column family.
    * @param columnFamilyOptions options to be used with
    *     column family.
+   * @deprecated will be removed in RocksDB 3.10.0. Use
+   * {@link #ColumnFamilyDescriptor(byte[], ColumnFamilyOptions)} instead.
    */
+  @Deprecated
   public ColumnFamilyDescriptor(final String columnFamilyName,
       final ColumnFamilyOptions columnFamilyOptions) {
+    this(columnFamilyName.getBytes(), columnFamilyOptions);
+  }
+
+  /**
+   * <p>Creates a new Column Family using a name and custom
+   * options.</p>
+   *
+   * @param columnFamilyName name of column family.
+   * @param columnFamilyOptions options to be used with
+   *     column family.
+   * @since 3.10.0
+   */
+  public ColumnFamilyDescriptor(final byte[] columnFamilyName,
+      final ColumnFamilyOptions columnFamilyOptions) {
     columnFamilyName_ = columnFamilyName;
     columnFamilyOptions_ = columnFamilyOptions;
   }
@@ -39,8 +70,9 @@ public class ColumnFamilyDescriptor {
    * Retrieve name of column family.
    *
    * @return column family name.
+   * @since 3.10.0
    */
-  public String columnFamilyName() {
+  public byte[] columnFamilyName() {
     return columnFamilyName_;
   }
 
@@ -53,6 +85,6 @@ public class ColumnFamilyDescriptor {
     return columnFamilyOptions_;
   }
 
-  private final String columnFamilyName_;
+  private final byte[] columnFamilyName_;
   private final ColumnFamilyOptions columnFamilyOptions_;
 }

java/org/rocksdb/RocksDB.java

@@ -16,7 +16,7 @@ import org.rocksdb.util.Environment;
  * indicates sth wrong at the RocksDB library side and the call failed.
  */
 public class RocksDB extends RocksObject {
-  public static final String DEFAULT_COLUMN_FAMILY = "default";
+  public static final byte[] DEFAULT_COLUMN_FAMILY = "default".getBytes();
   public static final int NOT_FOUND = -1;
 
   static {

java/org/rocksdb/test/AbstractComparatorTest.java

@@ -116,7 +116,7 @@ public abstract class AbstractComparatorTest {
         new ArrayList<>();
     cfDescriptors.add(new ColumnFamilyDescriptor(
         RocksDB.DEFAULT_COLUMN_FAMILY));
-    cfDescriptors.add(new ColumnFamilyDescriptor("new_cf",
+    cfDescriptors.add(new ColumnFamilyDescriptor("new_cf".getBytes(),
         new ColumnFamilyOptions().setComparator(
             getAscendingIntKeyComparator())));
     List<ColumnFamilyHandle> cfHandles = new ArrayList<>();

java/org/rocksdb/test/ColumnFamilyTest.java

@@ -68,7 +68,7 @@ public class ColumnFamilyTest {
       dbOptions.setCreateIfMissing(true);
 
       db = RocksDB.open(options, dbFolder.getRoot().getAbsolutePath());
-      db.createColumnFamily(new ColumnFamilyDescriptor("new_cf",
+      db.createColumnFamily(new ColumnFamilyDescriptor("new_cf".getBytes(),
           new ColumnFamilyOptions()));
       db.close();
       List<byte[]> columnFamilyNames;
@@ -102,7 +102,7 @@ public class ColumnFamilyTest {
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
       cfNames.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
-      cfNames.add(new ColumnFamilyDescriptor("new_cf"));
+      cfNames.add(new ColumnFamilyDescriptor("new_cf".getBytes()));
 
       db = RocksDB.open(options, dbFolder.getRoot().getAbsolutePath(),
           cfNames, columnFamilyHandleList);
@@ -191,12 +191,12 @@ public class ColumnFamilyTest {
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
       cfNames.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
-      cfNames.add(new ColumnFamilyDescriptor("new_cf"));
+      cfNames.add(new ColumnFamilyDescriptor("new_cf".getBytes()));
 
       db = RocksDB.open(opt, dbFolder.getRoot().getAbsolutePath(),
           cfNames, columnFamilyHandleList);
       tmpColumnFamilyHandle = db.createColumnFamily(
-          new ColumnFamilyDescriptor("tmpCF", new ColumnFamilyOptions()));
+          new ColumnFamilyDescriptor("tmpCF".getBytes(), new ColumnFamilyOptions()));
       db.put(tmpColumnFamilyHandle, "key".getBytes(), "value".getBytes());
       db.dropColumnFamily(tmpColumnFamilyHandle);
       tmpColumnFamilyHandle.dispose();
@@ -226,7 +226,7 @@ public class ColumnFamilyTest {
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
       cfNames.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
-      cfNames.add(new ColumnFamilyDescriptor("new_cf"));
+      cfNames.add(new ColumnFamilyDescriptor("new_cf".getBytes()));
 
       db = RocksDB.open(opt, dbFolder.getRoot().getAbsolutePath(),
           cfNames, columnFamilyHandleList);
@@ -273,7 +273,7 @@ public class ColumnFamilyTest {
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
       cfNames.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
-      cfNames.add(new ColumnFamilyDescriptor("new_cf"));
+      cfNames.add(new ColumnFamilyDescriptor("new_cf".getBytes()));
 
       db = RocksDB.open(options, dbFolder.getRoot().getAbsolutePath(),
           cfNames, columnFamilyHandleList);
@@ -322,7 +322,7 @@ public class ColumnFamilyTest {
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
       cfDescriptors.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
-      cfDescriptors.add(new ColumnFamilyDescriptor("new_cf"));
+      cfDescriptors.add(new ColumnFamilyDescriptor("new_cf".getBytes()));
 
       db = RocksDB.open(options, dbFolder.getRoot().getAbsolutePath(),
           cfDescriptors, columnFamilyHandleList);
@@ -367,7 +367,7 @@ public class ColumnFamilyTest {
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
       cfNames.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
-      cfNames.add(new ColumnFamilyDescriptor("new_cf"));
+      cfNames.add(new ColumnFamilyDescriptor("new_cf".getBytes()));
 
       db = RocksDB.open(options, dbFolder.getRoot().getAbsolutePath(),
           cfNames, columnFamilyHandleList);
@@ -409,7 +409,7 @@ public class ColumnFamilyTest {
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
       cfNames.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
-      cfNames.add(new ColumnFamilyDescriptor("new_cf"));
+      cfNames.add(new ColumnFamilyDescriptor("new_cf".getBytes()));
 
       db = RocksDB.open(options, dbFolder.getRoot().getAbsolutePath(),
           cfNames, columnFamilyHandleList);
@@ -459,7 +459,7 @@ public class ColumnFamilyTest {
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
       cfNames.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
-      cfNames.add(new ColumnFamilyDescriptor("new_cf"));
+      cfNames.add(new ColumnFamilyDescriptor("new_cf".getBytes()));
 
       db = RocksDB.open(options, dbFolder.getRoot().getAbsolutePath(),
           cfNames, columnFamilyHandleList);
@@ -487,7 +487,7 @@ public class ColumnFamilyTest {
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
       cfNames.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
-      cfNames.add(new ColumnFamilyDescriptor("new_cf"));
+      cfNames.add(new ColumnFamilyDescriptor("new_cf".getBytes()));
 
       db = RocksDB.open(options, dbFolder.getRoot().getAbsolutePath(),
           cfNames, columnFamilyHandleList);
@@ -515,7 +515,7 @@ public class ColumnFamilyTest {
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
       cfNames.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
-      cfNames.add(new ColumnFamilyDescriptor("new_cf"));
+      cfNames.add(new ColumnFamilyDescriptor("new_cf".getBytes()));
 
       db = RocksDB.open(options, dbFolder.getRoot().getAbsolutePath(),
           cfNames, columnFamilyHandleList);
@@ -543,7 +543,7 @@ public class ColumnFamilyTest {
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
       cfNames.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
-      cfNames.add(new ColumnFamilyDescriptor("new_cf"));
+      cfNames.add(new ColumnFamilyDescriptor("new_cf".getBytes()));
 
       db = RocksDB.open(options, dbFolder.getRoot().getAbsolutePath(),
           cfNames, columnFamilyHandleList);

java/org/rocksdb/test/KeyMayExistTest.java

@@ -37,8 +37,8 @@ public class KeyMayExistTest {
           new ArrayList<>();
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
-      cfDescriptors.add(new ColumnFamilyDescriptor("default"));
+      cfDescriptors.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
-      cfDescriptors.add(new ColumnFamilyDescriptor("new_cf"));
+      cfDescriptors.add(new ColumnFamilyDescriptor("new_cf".getBytes()));
       db = RocksDB.open(options,
           dbFolder.getRoot().getAbsolutePath(),
           cfDescriptors, columnFamilyHandleList);

java/org/rocksdb/test/MergeTest.java

@@ -8,7 +8,6 @@ package org.rocksdb.test;
 import java.util.List;
 import java.util.ArrayList;
 
-import org.junit.Assert;
 import org.junit.ClassRule;
 import org.junit.Rule;
 import org.junit.Test;
@@ -73,10 +72,10 @@ public class MergeTest {
 
       List<ColumnFamilyDescriptor> cfDescriptors =
           new ArrayList<>();
-      cfDescriptors.add(new ColumnFamilyDescriptor("default",
+      cfDescriptors.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY,
           new ColumnFamilyOptions().setMergeOperatorName(
               "stringappend")));
-      cfDescriptors.add(new ColumnFamilyDescriptor("default",
+      cfDescriptors.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY,
           new ColumnFamilyOptions().setMergeOperatorName(
               "stringappend")));
       db = RocksDB.open(opt, db_path_string,
@@ -158,10 +157,10 @@ public class MergeTest {
           new ArrayList<>();
       List<ColumnFamilyHandle> columnFamilyHandleList =
           new ArrayList<>();
-      cfDescriptors.add(new ColumnFamilyDescriptor("default",
+      cfDescriptors.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY,
           new ColumnFamilyOptions().setMergeOperator(
               stringAppendOperator)));
-      cfDescriptors.add(new ColumnFamilyDescriptor("new_cf",
+      cfDescriptors.add(new ColumnFamilyDescriptor("new_cf".getBytes(),
           new ColumnFamilyOptions().setMergeOperator(
               stringAppendOperator)));
       db = RocksDB.open(opt, db_path_string,
@@ -178,7 +177,7 @@ public class MergeTest {
 
       // Test also with createColumnFamily
       columnFamilyHandle = db.createColumnFamily(
-          new ColumnFamilyDescriptor("new_cf2",
+          new ColumnFamilyDescriptor("new_cf2".getBytes(),
               new ColumnFamilyOptions().setMergeOperator(stringAppendOperator)));
       // writing xx under cfkey2
       db.put(columnFamilyHandle, "cfkey2".getBytes(), "xx".getBytes());

java/org/rocksdb/test/ReadOnlyTest.java

@@ -58,9 +58,9 @@ public class ReadOnlyTest {
       db = RocksDB.open(
           dbFolder.getRoot().getAbsolutePath(), cfDescriptors, columnFamilyHandleList);
       columnFamilyHandleList.add(db.createColumnFamily(
-          new ColumnFamilyDescriptor("new_cf", new ColumnFamilyOptions())));
+          new ColumnFamilyDescriptor("new_cf".getBytes(), new ColumnFamilyOptions())));
       columnFamilyHandleList.add(db.createColumnFamily(
-          new ColumnFamilyDescriptor("new_cf2", new ColumnFamilyOptions())));
+          new ColumnFamilyDescriptor("new_cf2".getBytes(), new ColumnFamilyOptions())));
       db.put(columnFamilyHandleList.get(2), "key2".getBytes(),
           "value2".getBytes());
 
@@ -75,7 +75,7 @@ public class ReadOnlyTest {
           new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY,
               new ColumnFamilyOptions()));
       cfDescriptors.add(
-          new ColumnFamilyDescriptor("new_cf2", new ColumnFamilyOptions()));
+          new ColumnFamilyDescriptor("new_cf2".getBytes(), new ColumnFamilyOptions()));
       db3 = RocksDB.openReadOnly(
           dbFolder.getRoot().getAbsolutePath(), cfDescriptors, readOnlyColumnFamilyHandleList2);
       assertThat(new String(db3.get(readOnlyColumnFamilyHandleList2.get(1),

java/org/rocksdb/test/RocksDBTest.java

@@ -370,7 +370,7 @@ public class RocksDBTest {
       columnFamilyDescriptors.add(new ColumnFamilyDescriptor(
           RocksDB.DEFAULT_COLUMN_FAMILY));
       columnFamilyDescriptors.add(new ColumnFamilyDescriptor(
-          "new_cf",
+          "new_cf".getBytes(),
           new ColumnFamilyOptions().
               setDisableAutoCompactions(true).
               setCompactionStyle(CompactionStyle.LEVEL).
@@ -501,7 +501,7 @@ public class RocksDBTest {
       columnFamilyDescriptors.add(new ColumnFamilyDescriptor(
           RocksDB.DEFAULT_COLUMN_FAMILY));
       columnFamilyDescriptors.add(new ColumnFamilyDescriptor(
-          "new_cf",
+          "new_cf".getBytes(),
           new ColumnFamilyOptions().
               setDisableAutoCompactions(true).
               setCompactionStyle(CompactionStyle.LEVEL).
@@ -556,7 +556,7 @@ public class RocksDBTest {
       columnFamilyDescriptors.add(new ColumnFamilyDescriptor(
           RocksDB.DEFAULT_COLUMN_FAMILY));
       columnFamilyDescriptors.add(new ColumnFamilyDescriptor(
-          "new_cf",
+          "new_cf".getBytes(),
           new ColumnFamilyOptions().
               setDisableAutoCompactions(true).
               setCompactionStyle(CompactionStyle.LEVEL).
@@ -670,7 +670,7 @@ public class RocksDBTest {
       columnFamilyDescriptors.add(new ColumnFamilyDescriptor(
           RocksDB.DEFAULT_COLUMN_FAMILY));
       columnFamilyDescriptors.add(new ColumnFamilyDescriptor(
-          "new_cf",
+          "new_cf".getBytes(),
           new ColumnFamilyOptions().
               setDisableAutoCompactions(true).
               setCompactionStyle(CompactionStyle.LEVEL).

java/rocksjni/portal.h

@@ -172,7 +172,7 @@ class ColumnFamilyDescriptorJni {
   static jmethodID getColumnFamilyNameMethod(JNIEnv* env) {
     static jmethodID mid = env->GetMethodID(
         getColumnFamilyDescriptorClass(env),
-        "columnFamilyName", "()Ljava/lang/String;");
+        "columnFamilyName", "()[B");
     assert(mid != nullptr);
     return mid;
   }

java/rocksjni/rocksjni.cc

@@ -74,8 +74,8 @@ jobject
   rocksdb::DB* db = nullptr;
   const char* db_path = env->GetStringUTFChars(jdb_path, 0);
 
-  std::vector<const char*> cfnames_to_free;
+  std::vector<jbyte*> cfnames_to_free;
-  std::vector<jstring> jcfnames_for_free;
+  std::vector<jbyteArray> jcfnames_for_free;
 
   std::vector<rocksdb::ColumnFamilyDescriptor> column_families;
   std::vector<rocksdb::ColumnFamilyHandle* > handles;
@@ -90,22 +90,24 @@ jobject
       jobject jcf_descriptor = env->CallObjectMethod(iteratorObj,
           rocksdb::ListJni::getNextMethod(env));
       // get ColumnFamilyName
-      jstring jstr = (jstring) env->CallObjectMethod(jcf_descriptor,
+      jbyteArray byteArray = static_cast<jbyteArray>(env->CallObjectMethod(
+          jcf_descriptor,
           rocksdb::ColumnFamilyDescriptorJni::getColumnFamilyNameMethod(
-          env));
+              env)));
       // get CF Options
       jobject jcf_opt_obj = env->CallObjectMethod(jcf_descriptor,
           rocksdb::ColumnFamilyDescriptorJni::getColumnFamilyOptionsMethod(
-          env));
+              env));
       rocksdb::ColumnFamilyOptions* cfOptions =
           rocksdb::ColumnFamilyOptionsJni::getHandle(env, jcf_opt_obj);
 
-      const char* cfname = env->GetStringUTFChars(jstr, 0);
+      jbyte* cfname = env->GetByteArrayElements(byteArray, 0);
 
       // free allocated cfnames after call to open
       cfnames_to_free.push_back(cfname);
-      jcfnames_for_free.push_back(jstr);
+      jcfnames_for_free.push_back(byteArray);
-      column_families.push_back(rocksdb::ColumnFamilyDescriptor(cfname,
+      column_families.push_back(rocksdb::ColumnFamilyDescriptor(
+          reinterpret_cast<char *>(cfname),
           *cfOptions));
   }
 
@@ -116,7 +118,7 @@ jobject
   for (std::vector<jbyte*>::size_type i = 0;
       i != cfnames_to_free.size(); i++) {
     // free  cfnames
-    env->ReleaseStringUTFChars(jcfnames_for_free[i], cfnames_to_free[i]);
+    env->ReleaseByteArrayElements(jcfnames_for_free[i], cfnames_to_free[i], 0);
   }
 
   // check if open operation was successful
@@ -157,8 +159,8 @@ jobject Java_org_rocksdb_RocksDB_open__JLjava_lang_String_2Ljava_util_List_2I(
   rocksdb::DB* db = nullptr;
   const char* db_path = env->GetStringUTFChars(jdb_path, 0);
 
-  std::vector<const char*> cfnames_to_free;
+  std::vector<jbyte*> cfnames_to_free;
-  std::vector<jstring> jcfnames_for_free;
+  std::vector<jbyteArray> jcfnames_for_free;
 
   std::vector<rocksdb::ColumnFamilyDescriptor> column_families;
   std::vector<rocksdb::ColumnFamilyHandle* > handles;
@@ -173,22 +175,24 @@ jobject Java_org_rocksdb_RocksDB_open__JLjava_lang_String_2Ljava_util_List_2I(
       jobject jcf_descriptor = env->CallObjectMethod(iteratorObj,
           rocksdb::ListJni::getNextMethod(env));
       // get ColumnFamilyName
-      jstring jstr = (jstring) env->CallObjectMethod(jcf_descriptor,
+      jbyteArray byteArray = static_cast<jbyteArray>(env->CallObjectMethod(
+          jcf_descriptor,
           rocksdb::ColumnFamilyDescriptorJni::getColumnFamilyNameMethod(
-          env));
+              env)));
       // get CF Options
       jobject jcf_opt_obj = env->CallObjectMethod(jcf_descriptor,
           rocksdb::ColumnFamilyDescriptorJni::getColumnFamilyOptionsMethod(
-          env));
+              env));
       rocksdb::ColumnFamilyOptions* cfOptions =
           rocksdb::ColumnFamilyOptionsJni::getHandle(env, jcf_opt_obj);
 
-      const char* cfname = env->GetStringUTFChars(jstr, 0);
+      jbyte* cfname = env->GetByteArrayElements(byteArray, 0);
 
       // free allocated cfnames after call to open
       cfnames_to_free.push_back(cfname);
-      jcfnames_for_free.push_back(jstr);
+      jcfnames_for_free.push_back(byteArray);
-      column_families.push_back(rocksdb::ColumnFamilyDescriptor(cfname,
+      column_families.push_back(rocksdb::ColumnFamilyDescriptor(
+          reinterpret_cast<const char *>(cfname),
           *cfOptions));
   }
 
@@ -199,7 +203,7 @@ jobject Java_org_rocksdb_RocksDB_open__JLjava_lang_String_2Ljava_util_List_2I(
   for (std::vector<jbyte*>::size_type i = 0;
       i != cfnames_to_free.size(); i++) {
     // free  cfnames
-    env->ReleaseStringUTFChars(jcfnames_for_free[i], cfnames_to_free[i]);
+    env->ReleaseByteArrayElements(jcfnames_for_free[i], cfnames_to_free[i], 0);
   }
 
   // check if open operation was successful
@@ -1181,20 +1185,22 @@ jlong Java_org_rocksdb_RocksDB_createColumnFamily(
   rocksdb::ColumnFamilyHandle* handle;
   auto db_handle = reinterpret_cast<rocksdb::DB*>(jdb_handle);
 
-  jstring jstr = (jstring) env->CallObjectMethod(jcf_descriptor,
+  // get ColumnFamilyName
+  jbyteArray byteArray = static_cast<jbyteArray>(env->CallObjectMethod(
+      jcf_descriptor,
       rocksdb::ColumnFamilyDescriptorJni::getColumnFamilyNameMethod(
-      env));
+          env)));
   // get CF Options
   jobject jcf_opt_obj = env->CallObjectMethod(jcf_descriptor,
       rocksdb::ColumnFamilyDescriptorJni::getColumnFamilyOptionsMethod(
-      env));
+          env));
   rocksdb::ColumnFamilyOptions* cfOptions =
       rocksdb::ColumnFamilyOptionsJni::getHandle(env, jcf_opt_obj);
 
-  const char* cfname = env->GetStringUTFChars(jstr, 0);
+  jbyte* cfname = env->GetByteArrayElements(byteArray, 0);
   rocksdb::Status s = db_handle->CreateColumnFamily(
-      *cfOptions, cfname, &handle);
+      *cfOptions, reinterpret_cast<char *>(cfname), &handle);
-  env->ReleaseStringUTFChars(jstr, cfname);
+  env->ReleaseByteArrayElements(byteArray, cfname, 0);
 
   if (s.ok()) {
     return reinterpret_cast<jlong>(handle);