/*
    *    Copyright 2009-2023 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
    *
    *       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 org.apache.ibatis.reflection;
  
  import java.util.Arrays;
  
  /**
   * Provides hashCode, equals and toString methods that can handle array.
   */
  public class ArrayUtil {
  
    /**
     * Returns a hash code for {@code obj}.
     *
     * @param obj
     *          The object to get a hash code for. May be an array or <code>null</code>.
     *
     * @return A hash code of {@code obj} or 0 if {@code obj} is <code>null</code>
     */
    public static int hashCode(Object obj) {
      if (obj == null) {
        // for consistency with Arrays#hashCode() and Objects#hashCode()
        return 0;
      }
      final Class<?> clazz = obj.getClass();
      if (!clazz.isArray()) {
        return obj.hashCode();
      }
      final Class<?> componentType = clazz.getComponentType();
      if (long.class.equals(componentType)) {
        return Arrays.hashCode((long[]) obj);
      }
      if (int.class.equals(componentType)) {
        return Arrays.hashCode((int[]) obj);
      } else if (short.class.equals(componentType)) {
        return Arrays.hashCode((short[]) obj);
      } else if (char.class.equals(componentType)) {
        return Arrays.hashCode((char[]) obj);
      } else if (byte.class.equals(componentType)) {
        return Arrays.hashCode((byte[]) obj);
      } else if (boolean.class.equals(componentType)) {
        return Arrays.hashCode((boolean[]) obj);
      } else if (float.class.equals(componentType)) {
        return Arrays.hashCode((float[]) obj);
      } else if (double.class.equals(componentType)) {
        return Arrays.hashCode((double[]) obj);
      } else {
        return Arrays.hashCode((Object[]) obj);
      }
    }
  
    /**
     * Compares two objects. Returns <code>true</code> if
     * <ul>
     * <li>{@code thisObj} and {@code thatObj} are both <code>null</code></li>
     * <li>{@code thisObj} and {@code thatObj} are instances of the same type and {@link Object#equals(Object)} returns
     * <code>true</code></li>
     * <li>{@code thisObj} and {@code thatObj} are arrays with the same component type and equals() method of
     * {@link Arrays} returns <code>true</code> (not deepEquals())</li>
     * </ul>
     *
     * @param thisObj
     *          The left hand object to compare. May be an array or <code>null</code>
     * @param thatObj
     *          The right hand object to compare. May be an array or <code>null</code>
     *
     * @return <code>true</code> if two objects are equal; <code>false</code> otherwise.
     */
    public static boolean equals(Object thisObj, Object thatObj) {
      if (thisObj == null) {
        return thatObj == null;
      }
      if (thatObj == null) {
        return false;
      }
      final Class<?> clazz = thisObj.getClass();
      if (!clazz.equals(thatObj.getClass())) {
        return false;
      }
      if (!clazz.isArray()) {
        return thisObj.equals(thatObj);
      }
      final Class<?> componentType = clazz.getComponentType();
      if (long.class.equals(componentType)) {
        return Arrays.equals((long[]) thisObj, (long[]) thatObj);
      }
     if (int.class.equals(componentType)) {
       return Arrays.equals((int[]) thisObj, (int[]) thatObj);
     } else if (short.class.equals(componentType)) {
       return Arrays.equals((short[]) thisObj, (short[]) thatObj);
     } else if (char.class.equals(componentType)) {
       return Arrays.equals((char[]) thisObj, (char[]) thatObj);
     } else if (byte.class.equals(componentType)) {
       return Arrays.equals((byte[]) thisObj, (byte[]) thatObj);
     } else if (boolean.class.equals(componentType)) {
       return Arrays.equals((boolean[]) thisObj, (boolean[]) thatObj);
     } else if (float.class.equals(componentType)) {
       return Arrays.equals((float[]) thisObj, (float[]) thatObj);
     } else if (double.class.equals(componentType)) {
       return Arrays.equals((double[]) thisObj, (double[]) thatObj);
     } else {
       return Arrays.equals((Object[]) thisObj, (Object[]) thatObj);
     }
   }
 
   /**
    * If the {@code obj} is an array, toString() method of {@link Arrays} is called. Otherwise {@link Object#toString()}
    * is called. Returns "null" if {@code obj} is <code>null</code>.
    *
    * @param obj
    *          An object. May be an array or <code>null</code>.
    *
    * @return String representation of the {@code obj}.
    */
   public static String toString(Object obj) {
     if (obj == null) {
       return "null";
     }
     final Class<?> clazz = obj.getClass();
     if (!clazz.isArray()) {
       return obj.toString();
     }
     final Class<?> componentType = obj.getClass().getComponentType();
     if (long.class.equals(componentType)) {
       return Arrays.toString((long[]) obj);
     }
     if (int.class.equals(componentType)) {
       return Arrays.toString((int[]) obj);
     } else if (short.class.equals(componentType)) {
       return Arrays.toString((short[]) obj);
     } else if (char.class.equals(componentType)) {
       return Arrays.toString((char[]) obj);
     } else if (byte.class.equals(componentType)) {
       return Arrays.toString((byte[]) obj);
     } else if (boolean.class.equals(componentType)) {
       return Arrays.toString((boolean[]) obj);
     } else if (float.class.equals(componentType)) {
       return Arrays.toString((float[]) obj);
     } else if (double.class.equals(componentType)) {
       return Arrays.toString((double[]) obj);
     } else {
       return Arrays.toString((Object[]) obj);
     }
   }
 
   private ArrayUtil() {
   }
 
 }