Allow setting CDI SPI implementations repeatedly

api/src/main/java/jakarta/enterprise/inject/build/compatible/spi/BuildServicesResolver.java

@@ -76,16 +76,11 @@ private static void discoverFactories() {
      *
      * @param instance a {@link BuildServices} instance that should be used, must not be {@code null}
      * @throws IllegalArgumentException if the provided argument is null
-     * @throws IllegalStateException if the {@link BuildServices} are already set
      */
     public static void setBuildServices(BuildServices instance) {
         if (instance == null) {
             throw new IllegalArgumentException("BuildServices instance must not be null");
         }
-        if (configuredBuildServices == null) {
-            configuredBuildServices = instance;
-        } else {
-            throw new IllegalStateException("BuildServices cannot be set repeatedly. Existing BuildServices are " + configuredBuildServices);
-        }
+        configuredBuildServices = instance;
     }
 }

api/src/main/java/jakarta/enterprise/inject/spi/CDI.java

@@ -116,19 +116,14 @@ private static boolean checkProvider(CDIProvider c) {
      * </p>
      *
      * @param provider the provider to use
-     * @throws IllegalStateException if the {@link CDIProvider} is already set
      * @throws IllegalArgumentException if the provided argument is null
      */
     public static void setCDIProvider(CDIProvider provider) {
         if (provider == null) {
             throw new IllegalArgumentException("CDIProvider must not be null");
         }
-        if (configuredProvider == null) {
-            providerSetManually = true;
-            configuredProvider = provider;
-        } else {
-            throw new IllegalStateException("CDIProvider cannot be set repeatedly. Existing provider is " + configuredProvider);
-        }
+        providerSetManually = true;
+        configuredProvider = provider;
     }
 
     private static void findAllProviders() {