How to determine whether an object is empty in java

Method to determine whether a Java object is null:

First, directly use object == null to determine, and return when the object is null true, returns false when it is not null. Then, when object != null is true, further determine whether all properties of the object are null.

Example:

package com.gj5u.publics.util;
  
import java.util.List;
  
/**
 * 判断对象是否为空
 * 
 * @author Rex
 *
 */
public class EmptyUtil
{
  /**
   * 判断对象为空
   * 
   * @param obj
   *      对象名
   * @return 是否为空
   */
  @SuppressWarnings("rawtypes")
  public static boolean isEmpty(Object obj)
  {
    if (obj == null)
    {
      return true;
    }
    if ((obj instanceof List))
    {
      return ((List) obj).size() == 0;
    }
    if ((obj instanceof String))
    {
      return ((String) obj).trim().equals("");
    }
    return false;
  }
   
  /**
   * 判断对象不为空
   * 
   * @param obj
   *      对象名
   * @return 是否不为空
   */
  public static boolean isNotEmpty(Object obj)
  {
    return !isEmpty(obj);
  }
}

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