java 实验七 对象集合 实验报告(3)

5) 利用迭代遍历（课本227页），对List 中所有的工人调用work 方法。 答：该题代码如下：

package zi;

import java.util.ArrayList; import java.util.Iterator; import java.util.List; classWorker { privateintage; private String name; privatedoublesalary; public Worker (){}

public Worker (String name, int age, double salary){ this.name = name; this.age = age; this.salary = salary; }

publicint getAge() { returnage; }

publicvoid setAge(int age) { this.age = age; }

public String getName() { returnname; }

publicvoid setName(String name) { this.name = name; }

publicdouble getSalary(){ returnsalary; }

publicvoid setSalary(double salary){ this.salary = salary; }

publicvoid work(){

System.out.println(name + \); }

@Override

public String toString() {

return\ + age + \ + name + \ + salary + \; } }

publicclass Ex7_3_5{

publicstaticvoid main(String args[]){ List list=new ArrayList(); Worker w1=new Worker(\赵一\,30,5600); Worker w2=new Worker(\钱二\,21,3800); Worker w3=new Worker(\孙三\,28,4200); list.add(w1); list.add(1, w2); list.add(w2); list.add(w3);

Worker w4=new Worker(\孙三\,28,4200); list.remove(3);

for (int i = 0; i < list.size(); i++) { System.out.println(list.get(i));

Iterator iterator = list.iterator(); while(iterator.hasNext()){

System.out.println(iterator.next()); } } }

}

其运行结果截图如下：

6) 为Worker 类添加equals 方法，判断是否两个记录是否同一个人，并测试。

答：该题代码如下：

package zi;

import java.util.ArrayList; import java.util.Iterator; import java.util.List; classWorker { privateintage; private String name; privatedoublesalary; public Worker (){}

public Worker (String name, int age, double salary){ this.name = name; this.age = age; this.salary = salary; }

publicint getAge() { returnage; }

publicvoid setAge(int age) { this.age = age; }

public String getName() { returnname; }

publicvoid setName(String name) { this.name = name; }

publicdouble getSalary(){ returnsalary; }

publicvoid setSalary(double salary){ this.salary = salary; }

publicvoid work(){

System.out.println(name + \); }

@Override

public String toString() {

return\ + age + \ + name + \ + salary + \; } }

publicclass Ex7_3_6{

publicstaticvoid main(String args[]){

List list=new ArrayList(); Worker w1=new Worker(\赵一\,30,5600); Worker w2=new Worker(\钱二\,21,3800); Worker w3=new Worker(\孙三\,28,4200);

list.add(w1); list.add(w2); list.add(w3);

Worker w4=new Worker(\陈四\,24,3300); list.add(1, w4); list.remove(3);

Iterator i=list.iterator(); while (i.hasNext()) {

Worker worker = (Worker) i.next(); worker.work(); } }

publicboolean equals(Worker w1) { ))

returntrue; returnfalse; }

publicboolean equals(Object obj) {

returnsuper.equals(obj); } }

if(w1 == null)returnfalse; elseif

(this.name==w1.getName()&&this.age==w1.getAge()&&this.salary==w1.getSalary(

其运行结果截图如下：

4.（Map）已知某学校的教学课程内容安排如下：

完成下列要求：

1）使用一个Map，以老师的名字作为键，以老师教授的课程名作为值，表示上述课程安排。

2）增加了一位新老师Allen 教JDBC 3） Lucy 改为教CoreJava

4）遍历Map，输出所有的老师及老师教授的课程 5）利用Map，输出所有教JSP 的老师。

答：依据题意，其代码如下：

package zi;

import java.util.*; publicclass Ex7_4 {

publicstaticvoid main(String[] args) { //1)

Map map = newHashMap(); map.put(\, \); map.put(\, \); map.put(\, \); map.put(\, \); map.put(\, \); map.put(\, \); map.put(\, \);

//2) 增加了一个Allen教JDBC map.put(\, \);

//3) Lucy改教CoreJava

map.put(\, \);

//遍历Map

Set set = map.keySet();