Prepare release 5.4.2

Author: greenrobot-team

CHANGELOG.md

@@ -4,9 +4,11 @@ Notable changes to the ObjectBox Java library.
 
 For more insights into what changed in the database libraries, [check the ObjectBox C changelog](https://github.com/objectbox/objectbox-c/blob/main/CHANGELOG.md).
 
-## 5.4.2-preview1 - 2026-04-28
+## 5.4.2 - 2026-05-05
 
 - Update Android and JVM libraries to database version `5.3.2-2026-05-05`
+  - Fixed a corner case with "unique replace on conflict" and absent (e.g. null) sync clock value
+  - Internal fixes and improvements
 
 ## 5.4.1 - 2026-03-26
 

README.md

@@ -151,7 +151,7 @@ agp = "AGP_VERSION"
 kotlin = "KOTLIN_VERSION"
 
 # Define a variable for the version of the ObjectBox plugin
-objectbox = "5.4.2-preview1"
+objectbox = "5.4.2"
 
 [plugins]
 # For an Android project, using Android Gradle Plugin 9.0 or newer
@@ -251,7 +251,7 @@ Your project can now use ObjectBox, continue by [defining entity classes](https:
 
 plugins {
     // Add the ObjectBox plugin
-    id("io.objectbox") version "5.4.2-preview1" apply false
+    id("io.objectbox") version "5.4.2" apply false
 }
 ```
 
@@ -283,7 +283,7 @@ dependencyResolutionManagement {
 
 buildscript {
     // Define a variable for the ObjectBox plugin version
-    val objectboxVersion by extra("5.4.2-preview1")
+    val objectboxVersion by extra("5.4.2")
 
     repositories {
         // Add Maven Central to the plugin repositories     
@@ -313,7 +313,7 @@ allprojects {
 
 buildscript {
     // Define a variable for the ObjectBox plugin version
-    ext.objectboxVersion = "5.4.2-preview1"
+    ext.objectboxVersion = "5.4.2"
   
     repositories {        
         // Add Maven Central to the plugin repositories

build.gradle.kts

@@ -33,7 +33,7 @@ buildscript {
 
     // Version of Maven artifacts
     // Should only be changed as part of the release process, see the release checklist in the objectbox repo
-    val versionNumber = "5.4.2-preview1"
+    val versionNumber = "5.4.2"
 
     // If OBX_RELEASE is set, build and depend on release versions. Doesn't publish a release.
     // See the release checklist in the objectbox repo on how to publish a release.

objectbox-java/src/main/java/io/objectbox/BoxStore.java

@@ -82,7 +82,7 @@ public class BoxStore implements Closeable {
      * ReLinker uses this as a suffix for the extracted shared library file. If different, it will update it. Should be
      * unique to avoid conflicts.
      */
-    public static final String JNI_VERSION = "5.3.1-2026-04-24";
+    public static final String JNI_VERSION = "5.3.2-2026-05-05";
 
     /**
      * The ObjectBox database version this Java library is known to work with.