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   /*
    * Copyright 2017 The Netty Project
    *
    * The Netty Project licenses this file to you under the Apache License,
    * version 2.0 (the "License"); you may not use this file except in compliance
    * with the License. You may obtain a copy of the License at:
    *
    *   https://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
   * License for the specific language governing permissions and limitations
   * under the License.
   */
  package io.netty.util.internal;
  
  import java.lang.reflect.AccessibleObject;
  
  public final class ReflectionUtil {
  
      private ReflectionUtil() { }
  
      /**
       * Try to call {@link AccessibleObject#setAccessible(boolean)} but will catch any {@link SecurityException} and
       * {@link java.lang.reflect.InaccessibleObjectException} and return it.
       * The caller must check if it returns {@code null} and if not handle the returned exception.
       */
      public static Throwable trySetAccessible(AccessibleObject object, boolean checkAccessible) {
          if (checkAccessible && !PlatformDependent0.isExplicitTryReflectionSetAccessible()) {
              return new UnsupportedOperationException("Reflective setAccessible(true) disabled");
          }
          try {
              object.setAccessible(true);
              return null;
          } catch (SecurityException e) {
              return e;
          } catch (RuntimeException e) {
              return handleInaccessibleObjectException(e);
          }
      }
  
      private static RuntimeException handleInaccessibleObjectException(RuntimeException e) {
          // JDK 9 can throw an inaccessible object exception here; since Netty compiles
          // against JDK 7 and this exception was only added in JDK 9, we have to weakly
          // check the type
          if ("java.lang.reflect.InaccessibleObjectException".equals(e.getClass().getName())) {
              return e;
          }
          throw e;
      }
  }