1 files changed, 268 insertions, 0 deletions
diff --git a/src/rocksdb/java/rocksjni/statistics.cc b/src/rocksdb/java/rocksjni/statistics.cc
new file mode 100644
index 000000000..bd405afa1
--- /dev/null
+++ b/src/rocksdb/java/rocksjni/statistics.cc
@@ -0,0 +1,268 @@
+// Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+//
+// This file implements the "bridge" between Java and C++ and enables
+// calling c++ ROCKSDB_NAMESPACE::Statistics methods from Java side.
+
+#include "rocksdb/statistics.h"
+
+#include <jni.h>
+
+#include <memory>
+#include <set>
+
+#include "include/org_rocksdb_Statistics.h"
+#include "rocksjni/cplusplus_to_java_convert.h"
+#include "rocksjni/portal.h"
+#include "rocksjni/statisticsjni.h"
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    newStatistics
+ * Signature: ()J
+ */
+jlong Java_org_rocksdb_Statistics_newStatistics__(JNIEnv* env, jclass jcls) {
+  return Java_org_rocksdb_Statistics_newStatistics___3BJ(env, jcls, nullptr, 0);
+}
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    newStatistics
+ * Signature: (J)J
+ */
+jlong Java_org_rocksdb_Statistics_newStatistics__J(
+    JNIEnv* env, jclass jcls, jlong jother_statistics_handle) {
+  return Java_org_rocksdb_Statistics_newStatistics___3BJ(
+      env, jcls, nullptr, jother_statistics_handle);
+}
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    newStatistics
+ * Signature: ([B)J
+ */
+jlong Java_org_rocksdb_Statistics_newStatistics___3B(JNIEnv* env, jclass jcls,
+                                                     jbyteArray jhistograms) {
+  return Java_org_rocksdb_Statistics_newStatistics___3BJ(env, jcls, jhistograms,
+                                                         0);
+}
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    newStatistics
+ * Signature: ([BJ)J
+ */
+jlong Java_org_rocksdb_Statistics_newStatistics___3BJ(
+    JNIEnv* env, jclass, jbyteArray jhistograms,
+    jlong jother_statistics_handle) {
+  std::shared_ptr<ROCKSDB_NAMESPACE::Statistics>* pSptr_other_statistics =
+      nullptr;
+  if (jother_statistics_handle > 0) {
+    pSptr_other_statistics =
+        reinterpret_cast<std::shared_ptr<ROCKSDB_NAMESPACE::Statistics>*>(
+            jother_statistics_handle);
+  }
+
+  std::set<uint32_t> histograms;
+  if (jhistograms != nullptr) {
+    const jsize len = env->GetArrayLength(jhistograms);
+    if (len > 0) {
+      jbyte* jhistogram = env->GetByteArrayElements(jhistograms, nullptr);
+      if (jhistogram == nullptr) {
+        // exception thrown: OutOfMemoryError
+        return 0;
+      }
+
+      for (jsize i = 0; i < len; i++) {
+        const ROCKSDB_NAMESPACE::Histograms histogram =
+            ROCKSDB_NAMESPACE::HistogramTypeJni::toCppHistograms(jhistogram[i]);
+        histograms.emplace(histogram);
+      }
+
+      env->ReleaseByteArrayElements(jhistograms, jhistogram, JNI_ABORT);
+    }
+  }
+
+  std::shared_ptr<ROCKSDB_NAMESPACE::Statistics> sptr_other_statistics =
+      nullptr;
+  if (pSptr_other_statistics != nullptr) {
+    sptr_other_statistics = *pSptr_other_statistics;
+  }
+
+  auto* pSptr_statistics =
+      new std::shared_ptr<ROCKSDB_NAMESPACE::StatisticsJni>(
+          new ROCKSDB_NAMESPACE::StatisticsJni(sptr_other_statistics,
+                                               histograms));
+
+  return GET_CPLUSPLUS_POINTER(pSptr_statistics);
+}
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    disposeInternal
+ * Signature: (J)V
+ */
+void Java_org_rocksdb_Statistics_disposeInternal(JNIEnv*, jobject,
+                                                 jlong jhandle) {
+  if (jhandle > 0) {
+    auto* pSptr_statistics =
+        reinterpret_cast<std::shared_ptr<ROCKSDB_NAMESPACE::Statistics>*>(
+            jhandle);
+    delete pSptr_statistics;
+  }
+}
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    statsLevel
+ * Signature: (J)B
+ */
+jbyte Java_org_rocksdb_Statistics_statsLevel(JNIEnv*, jobject, jlong jhandle) {
+  auto* pSptr_statistics =
+      reinterpret_cast<std::shared_ptr<ROCKSDB_NAMESPACE::Statistics>*>(
+          jhandle);
+  assert(pSptr_statistics != nullptr);
+  return ROCKSDB_NAMESPACE::StatsLevelJni::toJavaStatsLevel(
+      pSptr_statistics->get()->get_stats_level());
+}
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    setStatsLevel
+ * Signature: (JB)V
+ */
+void Java_org_rocksdb_Statistics_setStatsLevel(JNIEnv*, jobject, jlong jhandle,
+                                               jbyte jstats_level) {
+  auto* pSptr_statistics =
+      reinterpret_cast<std::shared_ptr<ROCKSDB_NAMESPACE::Statistics>*>(
+          jhandle);
+  assert(pSptr_statistics != nullptr);
+  auto stats_level =
+      ROCKSDB_NAMESPACE::StatsLevelJni::toCppStatsLevel(jstats_level);
+  pSptr_statistics->get()->set_stats_level(stats_level);
+}
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    getTickerCount
+ * Signature: (JB)J
+ */
+jlong Java_org_rocksdb_Statistics_getTickerCount(JNIEnv*, jobject,
+                                                 jlong jhandle,
+                                                 jbyte jticker_type) {
+  auto* pSptr_statistics =
+      reinterpret_cast<std::shared_ptr<ROCKSDB_NAMESPACE::Statistics>*>(
+          jhandle);
+  assert(pSptr_statistics != nullptr);
+  auto ticker = ROCKSDB_NAMESPACE::TickerTypeJni::toCppTickers(jticker_type);
+  uint64_t count = pSptr_statistics->get()->getTickerCount(ticker);
+  return static_cast<jlong>(count);
+}
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    getAndResetTickerCount
+ * Signature: (JB)J
+ */
+jlong Java_org_rocksdb_Statistics_getAndResetTickerCount(JNIEnv*, jobject,
+                                                         jlong jhandle,
+                                                         jbyte jticker_type) {
+  auto* pSptr_statistics =
+      reinterpret_cast<std::shared_ptr<ROCKSDB_NAMESPACE::Statistics>*>(
+          jhandle);
+  assert(pSptr_statistics != nullptr);
+  auto ticker = ROCKSDB_NAMESPACE::TickerTypeJni::toCppTickers(jticker_type);
+  return pSptr_statistics->get()->getAndResetTickerCount(ticker);
+}
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    getHistogramData
+ * Signature: (JB)Lorg/rocksdb/HistogramData;
+ */
+jobject Java_org_rocksdb_Statistics_getHistogramData(JNIEnv* env, jobject,
+                                                     jlong jhandle,
+                                                     jbyte jhistogram_type) {
+  auto* pSptr_statistics =
+      reinterpret_cast<std::shared_ptr<ROCKSDB_NAMESPACE::Statistics>*>(
+          jhandle);
+  assert(pSptr_statistics != nullptr);
+
+  // TODO(AR) perhaps better to construct a Java Object Wrapper that
+  //    uses ptr to C++ `new HistogramData`
+  ROCKSDB_NAMESPACE::HistogramData data;
+
+  auto histogram =
+      ROCKSDB_NAMESPACE::HistogramTypeJni::toCppHistograms(jhistogram_type);
+  pSptr_statistics->get()->histogramData(
+      static_cast<ROCKSDB_NAMESPACE::Histograms>(histogram), &data);
+
+  jclass jclazz = ROCKSDB_NAMESPACE::HistogramDataJni::getJClass(env);
+  if (jclazz == nullptr) {
+    // exception occurred accessing class
+    return nullptr;
+  }
+
+  jmethodID mid =
+      ROCKSDB_NAMESPACE::HistogramDataJni::getConstructorMethodId(env);
+  if (mid == nullptr) {
+    // exception occurred accessing method
+    return nullptr;
+  }
+
+  return env->NewObject(jclazz, mid, data.median, data.percentile95,
+                        data.percentile99, data.average,
+                        data.standard_deviation, data.max, data.count, data.sum,
+                        data.min);
+}
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    getHistogramString
+ * Signature: (JB)Ljava/lang/String;
+ */
+jstring Java_org_rocksdb_Statistics_getHistogramString(JNIEnv* env, jobject,
+                                                       jlong jhandle,
+                                                       jbyte jhistogram_type) {
+  auto* pSptr_statistics =
+      reinterpret_cast<std::shared_ptr<ROCKSDB_NAMESPACE::Statistics>*>(
+          jhandle);
+  assert(pSptr_statistics != nullptr);
+  auto histogram =
+      ROCKSDB_NAMESPACE::HistogramTypeJni::toCppHistograms(jhistogram_type);
+  auto str = pSptr_statistics->get()->getHistogramString(histogram);
+  return env->NewStringUTF(str.c_str());
+}
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    reset
+ * Signature: (J)V
+ */
+void Java_org_rocksdb_Statistics_reset(JNIEnv* env, jobject, jlong jhandle) {
+  auto* pSptr_statistics =
+      reinterpret_cast<std::shared_ptr<ROCKSDB_NAMESPACE::Statistics>*>(
+          jhandle);
+  assert(pSptr_statistics != nullptr);
+  ROCKSDB_NAMESPACE::Status s = pSptr_statistics->get()->Reset();
+  if (!s.ok()) {
+    ROCKSDB_NAMESPACE::RocksDBExceptionJni::ThrowNew(env, s);
+  }
+}
+
+/*
+ * Class:     org_rocksdb_Statistics
+ * Method:    toString
+ * Signature: (J)Ljava/lang/String;
+ */
+jstring Java_org_rocksdb_Statistics_toString(JNIEnv* env, jobject,
+                                             jlong jhandle) {
+  auto* pSptr_statistics =
+      reinterpret_cast<std::shared_ptr<ROCKSDB_NAMESPACE::Statistics>*>(
+          jhandle);
+  assert(pSptr_statistics != nullptr);
+  auto str = pSptr_statistics->get()->ToString();
+  return env->NewStringUTF(str.c_str());
+}