问题 单项选择题

指出下面哪一项是在抽象类中声明一个抽象方法。( )

A.public abstract method();

B.public abstract void method();

C.public void abstract Method();

D.public void method() {abstract;}

答案

参考答案:B

解析: 本题考查在Java抽象类中声明抽象方法的格式。在Java语言中,将abstract关键字修饰的类称为抽象类。与此相对应,用abstract关键字修饰的方法称为抽象方法。当一个类的定义完全表示抽象的概念时,它不应该被实例化为一个对象,因此不能为抽象类实例化对象,也就是说,abstract类必须被继承。与此相应,abstract方法必须被重写。抽象类中可以包含抽象方法,对抽象方法只须声明,而不需要实现具体的内容,格式为 abstract retumType MethodName([paramlist])。对于抽象方法声明格式,abstract关键字不能缺少,此外,还需要注意如下内容: ① 声明格式中没有{};② 最后的“;”不能缺少;③ 可以用public或protected关键字来修饰。 选项A错误,缺少返回类型;选项B正确; 选项C错误,返回类型要跟在abstract后面; 选项D错误,抽象方法中不需要有具体的实现内容,更不需要{}。

单项选择题

How many really suffer as a result of labor market problems This is one of the most critical yet contentious social policy questions. In many ways, our social statistics exaggerate the degree of hardship. Unemployment does not have the same dire consequences today as it did in the 1930’s when most of the unemployed were primary breadwinners, when income and earnings were usually much closer to the margin of subsistence, and when there were no countervailing social programs for those failing in the labor market.

Increasing affluence, the rise of families with more than one wage earner, the growing predominance of secondary earners among the unemployed, and improved social welfare protection have unquestionably mitigated the consequences of joblessness. Earnings and income data also overstate the dimensions of hardship. Among the millions with hourly earnings at or below the minimum wage level, the over-whelming majority are from multiple earners, relatively affluent families. Most of those counted by the poverty statistics are elderly or handicapped or have family responsibilities which keep them out of the labor force, so the poverty statistics are by no means an accurate indicator of labor market pathologies.

Yet there are also many ways our social statistics underestimate the degree of labor-market-related hardship. The unemployment counts exclude the millions of fully employed workers whose wages are so low that their families remain in poverty. Low wages and repeated or prolonged unemployment frequently interact to undermine the capacity for self-support. Since the number experiencing joblessness at some time during the year is several times the number unemployed in any month, those who suffer as a result of forced idleness can equal or exceed average annual unemployment, even though only a minority of the jobless in any month really suffer. For every person counted in the monthly unemployment tallies, there is another working part-time because of the inability to find fulltime work, or else outside the labor force but wanting a job. Finally, income transfers in our country have always focused on the elderly, disabled, and dependent, neglecting the needs of the working poor, so that the dramatic expansion of cash and in kind transfers does not necessarily mean that those failing in the labor market are adequately protected.

As a result of such contradictory evidence, it is uncertain whether those suffering seriously as a result of thousands or the tens of millions, and, hence, whether high levels of joblessness can be tolerated or must be countered by job creation and economic stimulus. There is only one area of agreement in this debate—that the existing poverty, employment, and earnings statistics are inadequate for one of their primary applications, measuring the consequences of labor market problems.

Which of the tollowing does " labor market problems" in the first sentenee refer to()

A. Shortage of jobs providing adequate income

B. Deficiencies in the training of the work force

C. Trade relationships among producers of goods

D. The overall causes of poverty

问答题 简答题