java私有构造如何获取实例

问题遇到的现象和发生背景

怎么获取PropertyUtils的实例，想让他走这个私有构造器，外面怎么调用

问题相关代码，请勿粘贴截图

public class PropertyUtils extends PropertyUtilsBase {

private PropertyUtils(){
    this.init();
}

private static final PropertyUtilsBase propertyUtils = new PropertyUtils();

@Override
protected String getPropertiesFilePath() {
    return "common.hadoop.properties";
}

}

public class PropertyUtils extends PropertyUtilsBase{
    private PropertyUtils(){
        this.init();
    }

    private static final PropertyUtilsBase propertyUtils = new PropertyUtils();

    @Override
    protected String getPropertiesFilePath() {
        return "common.hadoop.properties";
    }

    /**
     * 获取propertyUtils
     * @return
     */
    public static PropertyUtilsBase getInstance(){
        return propertyUtils;
    }
}

外部获取，直接调用getInstance()方法

单例模式了解下：

public class PropertyUtils extends PropertyUtilsBase{
    private static final PropertyUtils propertyUtils = new PropertyUtils();  //恶汉模式
    private PropertyUtils(){}
    public static PropertyUtils getPropertyUtils(){
        return propertyUtils;
    }
}

public class PropertyUtils extends PropertyUtilsBase{
    private static PropertyUtils propertyUtils = null;  //懒汉模式
    private PropertyUtils(){}
    public static PropertyUtils getPropertyUtils(){
        if (propertyUtils==null){
            propertyUtils = new PropertyUtils();
            return propertyUtils;
        }else {
            return propertyUtils;
        }
    }
}

    public static void main(String[] args) {
        PropertyUtils propertyUtils = PropertyUtils.getPropertyUtils();
    }

class A extends B{
      private A(){}
      private static final A  a = new A();
      public static A getA(){
        return a
      }
}

获取： A.getA();

java 你都设置私有了 还调用这个构造干嘛 这就是java的规则
如果你想给其他类用这个构造函数
你就公开 或者像你封装字段一样封装这个构造函数