Bump up C++ version in JNI from c++11 to c++17. (#2259)

Signed-off-by: Dooyong Kim <[email protected]>
Co-authored-by: Dooyong Kim <[email protected]>

CHANGELOG.md

@@ -20,6 +20,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Introduced a writing layer in native engines where relies on the writing interface to process IO. (#2241)[https://github.com/opensearch-project/k-NN/pull/2241]
 ### Bug Fixes
 ### Infrastructure
+* Updated C++ version in JNI from c++11 to c++17 [#2259](https://github.com/opensearch-project/k-NN/pull/2259)
 ### Documentation
 ### Maintenance
 * Select index settings based on cluster version[2236](https://github.com/opensearch-project/k-NN/pull/2236)

jni/CMakeLists.txt

@@ -18,7 +18,7 @@ set(TARGET_LIB_NMSLIB opensearchknn_nmslib)  # nmslib JNI
 set(TARGET_LIB_FAISS opensearchknn_faiss)    # faiss JNI
 set(TARGET_LIBS "")  # Libs to be installed
 
-set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED True)
 option(CONFIG_FAISS "Configure faiss library build when this is on")
 option(CONFIG_NMSLIB "Configure nmslib library build when this is on")

src/test/java/org/opensearch/knn/index/memory/NativeMemoryCacheManagerTests.java

@@ -197,7 +197,7 @@ public void testGetTrainingSize() throws ExecutionException {
 
         nativeMemoryCacheManager.get(trainingDataEntryContext, true);
 
-        assertEquals((float) allocationEntryWeight, nativeMemoryCacheManager.getTrainingSizeInKilobytes(), 0.001);
+        assertEquals(allocationEntryWeight, nativeMemoryCacheManager.getTrainingSizeInKilobytes(), 1e-3);
         assertEquals(
             100 * (float) allocationEntryWeight / (float) maxWeight,
             nativeMemoryCacheManager.getTrainingSizeAsPercentage(),