HashMap的用法

*此示例演示HashMap的用法

***/
package maps;
import java.util.HashMap;
public class Test {

private HashMap map;

public Test()
{
map=new HashMap();
}

//添加Map
public void addMap()
{
Student stu1=new Student(1,"name1",60.08);
Student stu2=new Student(2,"name2",70.08);
Student stu3=new Student(3,"name3",80.08);
Student stu4=new Student(4,"name4",90.08);
map.put(stu1.getSno(), stu1);
map.put(stu2.getSno(), stu2);
map.put(stu3.getSno(), stu3);
map.put(stu4.getSno(), stu4);

}
//添加Map，如果Key存在则替换key对应的值，并返回替换的值。
public Object addMap(Object key,Object value)
{
return this.map.put(key, value);
}
//检查KEY
public boolean ContainsKey(Object key)
{
if(map.containsKey(key))
{
return true;
}else
{
return false;
}
}
//检查Value
public boolean ContainsValue(Object value)
{
if(map.containsValue(value))
{
return true;
}else
{
return false;
}
}
//获取Map大小
public int getSize()
{
return this.map.size();
}
//根据Key值移除元素，并返回移除的元素
public Object remove(Object key)
{
if(this.map.containsKey(key))
{
return this.map.remove(key);
}else
{
return null;
}
}
public static void main(String[] arges)
{

}
}

//Student 类

package maps;

public class Student {

private Integer sno;
private String sname;
private Double smark;

public Student(){}

public Student(Integer sno,String sname,Double smark)
{
this.sno=sno;
this.sname=sname;
this.smark=smark;
}
public Integer getSno() {
return sno;
}
public void setSno(Integer sno) {
this.sno = sno;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public Double getSmark() {
return smark;
}
public void setSmark(Double smark) {
this.smark = smark;
}
}