判断对象是否为空/不为空工具类

import java.util.Optional;


public final class NullUtil {
    private static final String NULL_STRING = "null";
    private static final int NULL_STRING_LENGTH = NULL_STRING.length();
    public NullUtil(){}
    /**
     * 判断参数是否不为null
     * @param object 判断参数
     * @return 如果object为空值(null)、空串("")或"null" 返回false,否则返回true
     */
    public static boolean isNotNull(Object object){
        if(object instanceof String){
            String temp = (String)object;
            final int len = temp.length();
            if (len > 0) {
                return len != NULL_STRING_LENGTH || !NULL_STRING.equalsIgnoreCase(temp);
            }else{
                return false;
            }
        }else{
            Optional<Object> optUserLogin = Optional.ofNullable(object);
            return optUserLogin.isPresent();
        }
    }

    /**
     * 判断参数是否为null
     * @param object 判断参数
     * @return 如果object为空值(null)、空串("")或"null" 返回true,否则返回false
     */
    public static boolean isNull(Object object){
        if(object instanceof String){
            String temp = (String)object;
            final int len = temp.length();
            if (len > 0) {
                return len == NULL_STRING_LENGTH && NULL_STRING.equalsIgnoreCase(temp);
            }else{
                return true;
            }
        }else{
            Optional<Object> optUserLogin = Optional.ofNullable(object);
            return !optUserLogin.isPresent();
        }
    }
}