集合 ArrayList 增删改除

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;

public class demo1 {

    /**
     * @param args
     * @throws IOException
     */
    public static void main(String[] args) throws IOException {
        // TODO Auto-generated method stub
        //创建雇员管理对象
        empmanage em = new empmanage();
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        //做个简易的菜单
        while(true)
        {
            System.out.println("请输入你要进行的操作:");
            System.out.println("1:表示要添加一个雇员");
            System.out.println("2:查找一个雇员");
            System.out.println("3:修改一个雇员工资");
            System.out.println("4:删除一个雇员");
            System.out.println("5:退出");
            String opertype = br.readLine();
            if(opertype.equals("1"))
            {
                System.out.println("请输入编号");
                String empno = br.readLine();
                System.out.println("请输入名字");
                String name = br.readLine();
                System.out.println("请输入薪资");
                float sal = Float.parseFloat(br.readLine());
                emp emp = new emp(empno,name,sal);
                em.addemp(emp);
            }
            else if(opertype.equals("2"))
            {
                System.out.println("请输入编号");
                String empno = br.readLine();
                em.showinfo(empno);
            }
            else if(opertype.equals("3"))
            {
                System.out.println("请输入编号 ");
                String empno = br.readLine();
                System.out.println("请输入新的工资");
                float newsal = Float.parseFloat(br.readLine());
                em.updatesal(empno, newsal);
            }
            else if(opertype.equals("4"))
            {
                System.out.println("请输入雇员号");
                String empno = br.readLine();
                em.delemp(empno);
            }else if(opertype.equals("5"))
            {
                System.exit(0);
            }
        }
    }

}
//雇员管理类
class empmanage{
    private ArrayList a1 = null;
    //构造
    public empmanage() {
        a1 = new ArrayList();
    }
    //加入员工
    public void addemp(emp emp){
        a1.add(emp);
    }
    //显示员工的相关信息
    public void showinfo(String empno) {
        //遍历整个ArrayList
        for(int i=1;i<a1.size();i++)
        {
            //去除emp对象
            emp emp = (emp)a1.get(i);
            //比较编号
            if(emp.getEmpNo().equals(empno))
            {
                System.out.println("找到雇员信息：");
                System.out.println("编号= "+emp.getEmpNo());
                System.out.println("名字= "+emp.getName());
                System.out.println("工资= "+emp.getSal());
            }
        }
    }
    //修改工资
    public void updatesal(String empno,float newsal) {
        for(int i=0;i<a1.size();i++)
        {
            emp emp = (emp)a1.get(i);
            if(emp.getEmpNo().equals(empno))
            {
                //修改薪水
                emp.setSal(newsal);
            }
        }
    }
    //删除雇员
    public void delemp(String empno) {
        for(int i=0;i<a1.size();i++)
        {
            emp emp =  (emp)a1.get(i);
            if(emp.getEmpNo().equals(empno))
            {
                a1.remove(i);
            }
        }
    }

}

/**
 * @author wyl
 * 雇员类
 */
class emp {
    //学号
    private String empNo;
    private String name;
    private float sal;
    //构造函数
    public emp(String empNo, String name, float sal) {
        super();
        this.empNo = empNo;
        this.name = name;
        this.sal = sal;
    }

    public String getEmpNo() {
        return empNo;
    }
    public void setEmpNo(String empNo) {
        this.empNo = empNo;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public float getSal() {
        return sal;
    }
    public void setSal(float sal) {
        this.sal = sal;
    }

}