/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements. See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF 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
    *
    *      http://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 org.apache.logging.log4j.util;
  
  import java.lang.reflect.Method;
  
  import org.apache.logging.log4j.LoggingException;
  import org.apache.logging.log4j.status.StatusLogger;
  
  /**
   * Base64 encodes Strings. This utility is only necessary because the mechanism to do this changed in Java 8 and
   * the original method was removed in Java 9.
   */
  public final class Base64Util {
  
      private static Method encodeMethod = null;
      private static Object encoder = null;
  
      static {
          try {
              Class<?> clazz = LoaderUtil.loadClass("java.util.Base64");
              Class<?> encoderClazz = LoaderUtil.loadClass("java.util.Base64$Encoder");
              Method method = clazz.getMethod("getEncoder");
              encoder = method.invoke(null);
              encodeMethod = encoderClazz.getMethod("encodeToString", byte[].class);
          } catch (Exception ex) {
              try {
                  Class<?> clazz = LoaderUtil.loadClass("javax.xml.bind.DataTypeConverter");
                  encodeMethod = clazz.getMethod("printBase64Binary");
              } catch (Exception ex2) {
                  LowLevelLogUtil.logException("Unable to create a Base64 Encoder", ex2);
              }
          }
      }
  
      private Base64Util() {
      }
  
      public static String encode(String str) {
          if (str == null) {
              return null;
          }
          byte [] data = str.getBytes();
          if (encodeMethod != null) {
              try {
                  return (String) encodeMethod.invoke(encoder, data);
              } catch (Exception ex) {
                  throw new LoggingException("Unable to encode String", ex);
              }
          }
          throw new LoggingException("No Encoder, unable to encode string");
      }
  }