1、利用白富美接口案例,土豪征婚使用匿名内部类对象实现
package com.cn;
public class Demo {
public static void main(String[] args) {
// TODO Auto-generated method stub
RichMan r = new RichMan();
r.marry(new IWhite(){
public void white() {
System.out.println("haha");
}
});
}
}
interface IWhite {
public abstract void white();
}
interface IRich {
public void rich();
}
interface IBeauti {
public void beauti();
}
interface IWRB extends IWhite, IRich, IBeauti {
}
class RichMan {
public void marry(IWhite i) {
System.out.println("白好");
i.white();
}
public void marry(IRich i) {
System.out.println("富很好");
i.rich();
}
public void marry(IBeauti i) {
System.out.println("美非常好");
i.beauti();
}
public void marry(IWRB i) {
System.out.println("白富美最好不过");
i.white();
i.rich();
i.beauti();
}
}
2.定义三角形类Trianle,里面包含三个int类型属性,分别表示三条边的长度,
构造三角形对象时,任意两边之和是否大于第三边,如若不成立,抛出自定义异常。
package com.cn;
public class Demo {
public static void main(String[] args) throws Exception {
Trianle t = new Trianle(1, 2, 3);
t.chech();
}
}
class myExcepton extends Exception {
String info;
public myExcepton(String info){
this.info = info;
}
}
class Trianle {
private int a;
private int b;
private int c;
public Trianle(int a,int b, int c){
this.a = a;
this.b = b;
this.c = c;
}
public void chech(int a,int b, int c) {
if (a + b < c || a + c < b || b + c < a) {
new myExcepton("bo bo ");
}
}
public void chech() throws Exception {
if (a + b < c || a + c < b || b + c < a) {
throw new myExcepton("bo bo ");
}
System.out.println("hao hao ");
}
}
3.Person类中增加birthday属性,对setBirthday(int ,int , int )方法进行异常处理,
要求年有效、月有效、日有效、年月日指定的具体日期有效,对不同情况分别抛出不同的异常。
答:
public class Brithday {
private String birthday;
public String getBirthday() {
return birthday;
}
public void setBirthday(int year, int month, int date)
throws InvalidParamExcetion {
if (year < 1900 || year > 2016) {
throw new InvalidParamExcetion("年份不合适,请传入1900年到2016年之间的年份");
}
if (month <= 0 || month > 12) {
throw new InvalidParamExcetion("月份不合适,不存在" + month + "月");
}
if (date > 31 || date <= 0) {
throw new InvalidParamExcetion("日期不合适,不存在" + date + "日");
}
boolean isThirdOne = date == 1 || date == 3 || date == 5 || date == 7
|| date == 8 || date == 10 || date == 12;
if (!isThirdOne && date == 31) {
throw new InvalidParamExcetion("日期不合适," + month + "月不存在" + date
+ "日");
}
if (month == 2 && date > 29) {
throw new InvalidParamExcetion("日期不合适,2月不存在" + date + "日");
}
if (year % 4 != 0 && month == 2 && date == 29) {
throw new InvalidParamExcetion("日期不合适," + year + "不是闰年,所以2月不存在"
+ date + "日");
}
System.out.println("生日为:" + year + "年" + month + "月 " + date + "日 ");
}
public static void main(String[] args) throws InvalidParamExcetion {
Brithday person = new Brithday();
try {
person.setBirthday(2015, 12, 5);
person.setBirthday(2016, 2, 29);
person.setBirthday(2015, 2, 29);
person.setBirthday(2015, 3, 5);
} catch (InvalidParamExcetion e) {
}
}
}
class InvalidParamExcetion extends Exception {
public InvalidParamExcetion(String msg) {
super(msg);
System.out.println(msg);
}
}