Replace getDeclaredConstructor().getInstance() with LoaderUtil

Author: ppkarwasz

log4j-api/src/main/java/org/apache/logging/log4j/LogManager.java

@@ -92,7 +92,7 @@ public class LogManager {
                     final Class<? extends LoggerContextFactory> factoryClass = provider.loadLoggerContextFactory();
                     if (factoryClass != null) {
                         try {
-                            factories.put(provider.getPriority(), factoryClass.getDeclaredConstructor().newInstance());
+                            factories.put(provider.getPriority(), LoaderUtil.newInstanceOf(factoryClass));
                         } catch (final Exception e) {
                             LOGGER.error("Unable to create class {} specified in provider URL {}",
                                     factoryClass.getName(), provider.getUrl(), e);

log4j-api/src/main/java/org/apache/logging/log4j/spi/ThreadContextMapFactory.java

@@ -21,6 +21,7 @@
 import org.apache.logging.log4j.ThreadContext;
 import org.apache.logging.log4j.status.StatusLogger;
 import org.apache.logging.log4j.util.Constants;
+import org.apache.logging.log4j.util.LoaderUtil;
 import org.apache.logging.log4j.util.PropertiesUtil;
 import org.apache.logging.log4j.util.ProviderUtil;
 
@@ -103,7 +104,7 @@ public static ThreadContextMap createThreadContextMap() {
                     final Class<? extends ThreadContextMap> clazz = provider.loadThreadContextMap();
                     if (clazz != null) {
                         try {
-                            result = clazz.getDeclaredConstructor().newInstance();
+                            result = LoaderUtil.newInstanceOf(clazz);
                             break;
                         } catch (final Exception e) {
                             LOGGER.error("Unable to locate or load configured ThreadContextMap {}",

log4j-core/src/main/java/org/apache/logging/log4j/core/impl/ContextDataFactory.java

@@ -55,8 +55,9 @@ public class ContextDataFactory {
      * In graalvm doc (https://github.com/oracle/graal/blob/master/substratevm/LIMITATIONS.md),
      * graalvm is not support MethodHandle now, so the Constructor need not to return MethodHandle.
      */
-    private static final Constructor<?> DEFAULT_CONSTRUCTOR = createDefaultConstructor(CACHED_CLASS);
-    private static final Constructor<?> INITIAL_CAPACITY_CONSTRUCTOR = createInitialCapacityConstructor(CACHED_CLASS);
+    private static final Constructor<? extends StringMap> DEFAULT_CONSTRUCTOR = createDefaultConstructor(CACHED_CLASS);
+    private static final Constructor<? extends StringMap> INITIAL_CAPACITY_CONSTRUCTOR =
+            createInitialCapacityConstructor(CACHED_CLASS);
 
     private static final StringMap EMPTY_STRING_MAP = createContextData(0);
 
@@ -75,7 +76,8 @@ private static Class<? extends StringMap> createCachedClass(final String classNa
         }
     }
 
-    private static Constructor<?> createDefaultConstructor(final Class<? extends StringMap> cachedClass){
+    private static Constructor<? extends StringMap> createDefaultConstructor(
+            final Class<? extends StringMap> cachedClass) {
         if (cachedClass == null) {
             return null;
         }
@@ -86,7 +88,8 @@ private static Constructor<?> createDefaultConstructor(final Class<? extends Str
         }
     }
 
-    private static Constructor<?> createInitialCapacityConstructor(final Class<? extends StringMap> cachedClass){
+    private static Constructor<? extends StringMap> createInitialCapacityConstructor(
+            final Class<? extends StringMap> cachedClass) {
         if (cachedClass == null) {
             return null;
         }
@@ -102,7 +105,7 @@ public static StringMap createContextData() {
             return new SortedArrayStringMap();
         }
         try {
-            return (IndexedStringMap) DEFAULT_CONSTRUCTOR.newInstance();
+            return DEFAULT_CONSTRUCTOR.newInstance();
         } catch (final Throwable ignored) {
             return new SortedArrayStringMap();
         }
@@ -113,7 +116,7 @@ public static StringMap createContextData(final int initialCapacity) {
             return new SortedArrayStringMap(initialCapacity);
         }
         try {
-            return (IndexedStringMap) INITIAL_CAPACITY_CONSTRUCTOR.newInstance(initialCapacity);
+            return INITIAL_CAPACITY_CONSTRUCTOR.newInstance(initialCapacity);
         } catch (final Throwable ignored) {
             return new SortedArrayStringMap(initialCapacity);
         }

log4j-core/src/main/java/org/apache/logging/log4j/core/net/MulticastDnsAdvertiser.java

@@ -135,7 +135,7 @@ public void unadvertise(final Object serviceInfo) {
 
     private static Object createJmDnsVersion1() {
         try {
-            return jmDNSClass.getConstructor().newInstance();
+            return LoaderUtil.newInstanceOf(jmDNSClass);
         } catch (final InstantiationException | IllegalAccessException | NoSuchMethodException | InvocationTargetException e) {
             LOGGER.warn("Unable to instantiate JMDNS", e);
         }