Fix JNI memory leak, add test for default column name.

Author: rhubner

java/rocksjni/portal.h

@@ -9276,12 +9276,14 @@ class WideColumnJni {
           op,
       JNIEnv* env, jbyteArray jkey, jint keyOffset, jint keyLen,
       jobjectArray jnames, jobjectArray jvalues) {
-    jbyte* key = new jbyte[keyLen];
-    env->GetByteArrayRegion(jkey, keyOffset, keyLen, key);
+    auto key = std::make_unique<jbyte[]>(keyLen);
+
+    env->GetByteArrayRegion(jkey, keyOffset, keyLen, key.get());
     if (env->ExceptionCheck()) {
       return;
     }
-    ROCKSDB_NAMESPACE::Slice key_slice(reinterpret_cast<char*>(key), keyLen);
+    ROCKSDB_NAMESPACE::Slice key_slice(reinterpret_cast<char*>(key.get()),
+                                       keyLen);
 
     const auto column_len = env->GetArrayLength(jnames);
     rocksdb::WideColumns columns;

java/src/test/java/org/rocksdb/WideColumnTest.java

@@ -54,6 +54,59 @@ public void simpleReadWrite() throws RocksDBException {
     }
   }
 
+  @Test
+  public void readKVAsWideColumn() throws RocksDBException {
+    try (final RocksDB db = RocksDB.open(dbFolder.getRoot().getAbsolutePath())) {
+      db.put(
+          "someKey".getBytes(StandardCharsets.UTF_8), "someValue".getBytes(StandardCharsets.UTF_8));
+
+      List<WideColumn<byte[]>> result = new ArrayList<>();
+
+      Status status = db.getEntity("someKey".getBytes(), result);
+
+      assertThat(status.getCode()).isEqualTo(Status.Code.Ok);
+
+      assertThat(result).isNotEmpty();
+
+      assertThat(result.get(0).getName()).isEqualTo(new byte[] {});
+
+      assertThat(result.get(0).getValue()).isEqualTo("someValue".getBytes(StandardCharsets.UTF_8));
+    }
+  }
+
+  @Test
+  public void readWideColumnAsKV() throws RocksDBException {
+    try (final RocksDB db = RocksDB.open(dbFolder.getRoot().getAbsolutePath())) {
+      List<WideColumn<byte[]>> wideColumns = new ArrayList<>();
+
+      wideColumns.add(new WideColumn<>("columnName".getBytes(StandardCharsets.UTF_8),
+          "columnValue".getBytes(StandardCharsets.UTF_8)));
+      db.putEntity("someKey".getBytes(StandardCharsets.UTF_8), wideColumns);
+
+      byte[] status = db.get("someKey".getBytes());
+
+      assertThat(status).isNotNull();
+    }
+  }
+
+  @Test
+  public void readWideDefaultColumnAsKV() throws RocksDBException {
+    try (final RocksDB db = RocksDB.open(dbFolder.getRoot().getAbsolutePath())) {
+      List<WideColumn<byte[]>> wideColumns = new ArrayList<>();
+
+      wideColumns.add(new WideColumn<>("columnName".getBytes(StandardCharsets.UTF_8),
+          "columnValue".getBytes(StandardCharsets.UTF_8)));
+      wideColumns.add(
+          new WideColumn<>(new byte[] {}, "defaultColumnValue".getBytes(StandardCharsets.UTF_8)));
+
+      db.putEntity("someKey".getBytes(StandardCharsets.UTF_8), wideColumns);
+
+      byte[] status = db.get("someKey".getBytes());
+
+      assertThat(status).isNotNull();
+      assertThat(status).isEqualTo("defaultColumnValue".getBytes(StandardCharsets.UTF_8));
+    }
+  }
   @Test
   public void readWriteWithKeyOffset() throws RocksDBException {
     try (final RocksDB db = RocksDB.open(dbFolder.getRoot().getAbsolutePath())) {