RealmInstant.now implementation on Android uses API 26 > minSDK 16

CHANGELOG.md

@@ -7,6 +7,7 @@
 * Support for experimental K2-compilation with `kotlin.experimental.tryK2=true`. (Issue [#1483](https://github.com/realm/realm-kotlin/issues/1483))
 
 ### Fixed
+* `RealmInstant.now` used an API (`java.time.Clock.systemUTC().instant()`) introduced in API 26, current minSDK is 16. (Issue [#1564](https://github.com/realm/realm-kotlin/issues/1564))
 * Fix compiler crash caused by a change in Kotlin 1.9.20 ((toIrConst moved under common IrUtils)[https://github.com/JetBrains/kotlin/commit/ca8db7d0b83f6dfd6afcea7a5fe7556d38f325d8]). (Issue [#1566](https://github.com/realm/realm-kotlin/issues/1566))
 
 ### Compatibility

packages/library-base/src/androidMain/kotlin/io/realm/kotlin/internal/platform/SystemUtilsAndroid.kt

@@ -1,10 +1,13 @@
 package io.realm.kotlin.internal.platform
 
+import android.os.Build
 import io.realm.kotlin.internal.RealmInitializer
+import io.realm.kotlin.internal.RealmInstantImpl
 import io.realm.kotlin.internal.interop.SyncConnectionParams
 import io.realm.kotlin.internal.util.Exceptions
 import io.realm.kotlin.log.LogLevel
 import io.realm.kotlin.log.RealmLogger
+import io.realm.kotlin.types.RealmInstant
 import java.io.FileNotFoundException
 import java.io.InputStream
 
@@ -36,3 +39,12 @@ public actual fun assetFileAsStream(assetFilename: String): InputStream = try {
 // Returns the default logger for the platform
 public actual fun createDefaultSystemLogger(tag: String, logLevel: LogLevel): RealmLogger =
     LogCatLogger(tag, logLevel)
+
+public actual fun currentTime(): RealmInstant {
+    return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+        val jtInstant = java.time.Clock.systemUTC().instant()
+        RealmInstantImpl(jtInstant.epochSecond, jtInstant.nano)
+    } else {
+        RealmInstantImpl(System.currentTimeMillis(), 0)
+    }
+}

packages/library-base/src/commonMain/kotlin/io/realm/kotlin/internal/platform/SystemUtils.kt

@@ -137,6 +137,7 @@ public expect fun epochInSeconds(): Long
 
 /**
  * Returns a RealmInstant representing the time that has passed since the Unix epoch.
+ * For Android targets < API 26 there's no nano seconds precision.
  */
 public expect fun currentTime(): RealmInstant
 

packages/library-base/src/jvm/kotlin/io/realm/kotlin/internal/platform/SystemUtils.kt

@@ -1,15 +1,12 @@
 package io.realm.kotlin.internal.platform
 
 import io.realm.kotlin.internal.Constants.FILE_COPY_BUFFER_SIZE
-import io.realm.kotlin.internal.RealmInstantImpl
 import io.realm.kotlin.internal.util.Exceptions
-import io.realm.kotlin.types.RealmInstant
 import java.io.File
 import java.io.InputStream
 import java.io.OutputStream
 import java.security.DigestInputStream
 import java.security.MessageDigest
-import java.time.Clock.systemUTC
 import java.util.concurrent.TimeUnit
 import kotlin.reflect.KMutableProperty1
 import kotlin.reflect.KType
@@ -24,15 +21,6 @@ public actual fun threadId(): ULong {
 public actual fun epochInSeconds(): Long =
     TimeUnit.MILLISECONDS.toSeconds(System.currentTimeMillis())
 
-/**
-* Since internalNow() should only logically return a value after the Unix epoch, it is safe to create a RealmInstant
-* without considering having to pass negative nanoseconds.
-*/
-public actual fun currentTime(): RealmInstant {
-    val jtInstant = systemUTC().instant()
-    return RealmInstantImpl(jtInstant.epochSecond, jtInstant.nano)
-}
-
 public actual fun fileExists(path: String): Boolean =
     File(path).let { it.exists() && it.isFile }
 

packages/library-base/src/jvmMain/kotlin/io/realm/kotlin/internal/platform/SystemUtilsJvm.kt

@@ -1,12 +1,15 @@
 package io.realm.kotlin.internal.platform
 
 import io.realm.kotlin.Realm
+import io.realm.kotlin.internal.RealmInstantImpl
 import io.realm.kotlin.internal.interop.SyncConnectionParams
 import io.realm.kotlin.internal.util.Exceptions
 import io.realm.kotlin.log.LogLevel
 import io.realm.kotlin.log.RealmLogger
+import io.realm.kotlin.types.RealmInstant
 import java.io.InputStream
 import java.net.URL
+import java.time.Clock
 
 public actual val RUNTIME: SyncConnectionParams.Runtime = SyncConnectionParams.Runtime.JVM
 public actual val RUNTIME_VERSION: String = System.getProperty("java.version")
@@ -27,3 +30,13 @@ public actual fun assetFileAsStream(assetFilename: String): InputStream {
 
 public actual fun createDefaultSystemLogger(tag: String, logLevel: LogLevel): RealmLogger =
     StdOutLogger(tag, logLevel)
+
+/**
+ * Since internalNow() should only logically return a value after the Unix epoch, it is safe to create a RealmInstant
+ * without considering having to pass negative nanoseconds.
+ */
+@Suppress("NewApi") // The implementation in SystemUtilsAndroid has a guard to only use systemUTC on API >= 26
+public actual fun currentTime(): RealmInstant {
+    val jtInstant = Clock.systemUTC().instant()
+    return RealmInstantImpl(jtInstant.epochSecond, jtInstant.nano)
+}

packages/library-sync/src/androidMain/kotlin/io/realm/kotlin/mongodb/internal/RealmSyncInitializer.kt

@@ -82,7 +82,7 @@ internal class RealmSyncInitializer : Initializer<Context> {
                 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP /* 21 */) {
                     val request = NetworkRequest.Builder()
                         .addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)
-                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP /* 23 */) {
+                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M /* 23 */) {
                         request.addCapability(NetworkCapabilities.NET_CAPABILITY_VALIDATED)
                     }
                     RealmLog.info("Register ConnectivityManager network callbacks")