ISPN-10863 java.lang.IllegalAccessException logged by PropertyFormatter

* should not attempt to access static or non-public methods and should
  mark them accessible to prevent eventual cross-module accessibility
  checks from failing

core/src/main/java/org/infinispan/configuration/format/PropertyFormatter.java

@@ -1,9 +1,9 @@
 package org.infinispan.configuration.format;
 
 import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Properties;
@@ -12,14 +12,15 @@
 import org.infinispan.configuration.global.GlobalConfiguration;
 
 /**
- *
  * Extracts the configuration into flat key-value property structure by reflection.
  *
  * @author Michal Linhard (mlinhard@redhat.com)
  * @since 6.0
  */
-public class PropertyFormatter {
+public final class PropertyFormatter {
+
    private static Method plainToString = null;
+
    static {
       try {
          plainToString = Object.class.getMethod("toString");
@@ -41,27 +42,40 @@ public PropertyFormatter() {
    /**
     * Create a new PropertyFormatter instance.
     *
-    * @param globalConfigPrefix
-    *           Prefix used for global configuration property keys.
-    * @param configPrefix
-    *           Prefix used for cache configuration property keys.
+    * @param globalConfigPrefix Prefix used for global configuration property keys.
+    * @param configPrefix       Prefix used for cache configuration property keys.
     */
    public PropertyFormatter(String globalConfigPrefix, String configPrefix) {
       this.globalConfigPrefix = globalConfigPrefix;
       this.configPrefix = configPrefix;
    }
 
-   private static List<Method> getMethods(Class<?> clazz) {
+   /**
+    * Get all public, non-static, non-deprecated methods with 0 arguments (except toString() and other unuuseful ones).
+    */
+   private static List<Method> getConfigMethods(Class<?> clazz) {
       Class<?> c = clazz;
       List<Method> r = new ArrayList<>();
       while (c != null && c != Object.class) {
-         Collections.addAll(r, c.getDeclaredMethods());
+         for (Method m : c.getDeclaredMethods()) {
+            if (Modifier.isPublic(m.getModifiers())
+                  && !Modifier.isStatic(m.getModifiers())
+                  && m.getParameters().length == 0
+                  && !m.isAnnotationPresent(Deprecated.class)
+                  && !"hashCode".equals(m.getName())
+                  && !"toString".equals(m.getName())
+                  && !"toProperties".equals(m.getName())) {
+               m.setAccessible(true);
+               r.add(m);
+            }
+         }
          c = c.getSuperclass();
       }
       return r;
    }
 
-   private static boolean hasPlainToString(Class<?> cls, Object obj) {
+   private static boolean hasPlainToString(Object obj) {
+      Class<?> cls = obj.getClass();
       try {
          if (cls.getMethod("toString") == plainToString) {
             return true;
@@ -81,14 +95,9 @@ private static void reflect(Object obj, Properties p, String prefix) {
          }
          Class<?> cls = obj.getClass();
          if (cls.getName().startsWith("org.infinispan.config") && !cls.isEnum()) {
-            for (Method m : getMethods(obj.getClass())) {
-               if (m.getParameterTypes().length != 0 || "toString".equals(m.getName())
-                     || "hashCode".equals(m.getName()) || "toProperties".equals(m.getName())
-                     || m.isAnnotationPresent(Deprecated.class)) {
-                  continue;
-               }
+            for (Method m : getConfigMethods(obj.getClass())) {
                try {
-                  String prefixDot = prefix == null || "".equals(prefix) ? "" : prefix + ".";
+                  String prefixDot = prefix == null || prefix.isEmpty() ? "" : prefix + ".";
                   reflect(m.invoke(obj), p, prefixDot + m.getName());
                } catch (IllegalAccessException e) {
                   // ok
@@ -105,7 +114,7 @@ private static void reflect(Object obj, Properties p, String prefix) {
             for (int i = 0; i < a.length; i++) {
                reflect(a[i], p, prefix + "[" + i + "]");
             }
-         } else if (hasPlainToString(cls, obj)) {
+         } else if (hasPlainToString(obj)) {
             // we have a class that doesn't have a nice toString implementation
             p.put(prefix, cls.getName());
          } else {