java - 未为参数类型定义运算符>，无效

嗨，我收到此Java代码的标题错误

public static void age(Ship ob){
    DateTime myBirthDate = ob.getDate();
    DateTime now = new DateTime();
    Period period = new Period(myBirthDate, now);

    System.out.print("Ship age is " + ob.getName() + " е " );

    PeriodFormatter formatter = new PeriodFormatterBuilder()
        .appendYears().appendSuffix(" years")
        .appendMonths().appendSuffix(" months")
        .appendWeeks().appendSuffix(" weeks")
        .appendDays().appendSuffix(" days")
        .appendHours().appendSuffix(" hours")
        .appendMinutes().appendSuffix(" mnutes")
        .appendSeconds().appendSuffix(" seconds\n ")
        .printZeroNever().toFormatter();

    String elapsed = formatter.print(period);
    System.out.println(elapsed);
}

public static void compare(Ship ob, Ship ob2) throws ParseException {
    if(age(ob2) > age(ob)){ //<---- I get the Error here , when i try to comapre two objects
        System.out.println( "The ship,wich is more years is " + ob2);
    } else
        System.out.println( "The ship,wich is more years is " + ob);
}

你能帮助我吗？我尝试了多种方法来修复此错误，但没有帮助，谢谢。

最佳答案

int compareResult = ob.getDate().compareTo(ob2.getDate());
if (compareResult > 0) //ob2 date after ob date
    else if (compareResult < 0) //ob2 date before ob
        else //ob2 has same date as ob

如果要练习OOP，像这样计算年龄是不好的。
您应该使年龄方法成为Ship类的成员。和/或在Ship类中具有一个比较方法，该方法可以接受另一艘Ship并返回日期/年龄比较的结果。

关于java - 未为参数类型定义运算符>，无效，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/19874826/