/*
    *    Copyright 2009-2021 the original author or authors.
    *
    *    Licensed 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.ibatis.io;
  
  import java.security.Security;
  
  import org.apache.ibatis.logging.Log;
  import org.apache.ibatis.logging.LogFactory;
  
  public final class SerialFilterChecker {
    private static final Log log = LogFactory.getLog(SerialFilterChecker.class);
    /* Property key for the JEP-290 serialization filters */
    private static final String JDK_SERIAL_FILTER = "jdk.serialFilter";
    private static final boolean SERIAL_FILTER_MISSING;
    private static boolean firstInvocation = true;
  
    static {
      Object serialFilter;
      try {
        Class<?> objectFilterConfig = Class.forName("java.io.ObjectInputFilter$Config");
        serialFilter = objectFilterConfig.getMethod("getSerialFilter").invoke(null);
      } catch (ReflectiveOperationException e) {
        // Java 1.8
        serialFilter = System.getProperty(JDK_SERIAL_FILTER, Security.getProperty(JDK_SERIAL_FILTER));
      }
      SERIAL_FILTER_MISSING = serialFilter == null;
    }
  
    public static void check() {
      if (firstInvocation && SERIAL_FILTER_MISSING) {
        firstInvocation = false;
        log.warn(
            "As you are using functionality that deserializes object streams, it is recommended to define the JEP-290 serial filter. "
                + "Please refer to https://docs.oracle.com/pls/topic/lookup?ctx=javase15&id=GUID-8296D8E8-2B93-4B9A-856E-0A65AF9B8C66");
      }
    }
  
    private SerialFilterChecker() {
    }
  }