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/*
需求：使用数组保存CD信息，实现增、删、查、打印的功能
思想：1.建立一个CD类，存储CD基本信息
2、建立一个CDManager类，定义对CD的操作
3、建立一个MainInput类，定义一些信息输入的操作
*/
import java.util.Vector;
import java.io.*;
//CD类
class CD
{
String cdid;
String cdname;
float price;
String press;
CD(){}
CD(String cdid,String cdname,float price,String press)
{
this.cdid=cdid;
this.cdname=cdname;
this.price=price;
this.press=press;
}
void setID(String cdid)
{
this.cdid=cdid;
}
void setName(String cdname)
{
this.cdname=cdname;
}
void setPrice(float price)
{
this.price=price;
}
void setPress(String press)
{
this.press=press;
}
}
//定义对CD类的一些操作
class CDManager
{
Vector vec;
int count=0;
CDManager()
{
vec = new Vector(50,1);
}
public void addCD(CD c) //添加CD
{
//vec.addElement(c);
vec.insertElementAt(c,count++);
}
public int findCDById(String id)//查找CD，按ID
{
CD getcd = new CD();
for(int i=0;i<vec.size();i++)
{
getcd = (CD) vec.elementAt(i);
if(id == getcd.cdid)
{
return i;
}
}
return -1;
}
public int removeCDById(String id)//删除CD，按ID
{
for(int i=0;i<vec.size();i++)
{
if(id == ((CD)vec.elementAt(i)).cdid)
{
vec.removeElementAt(i);
return 1;
}
}
return -1;
}
public void printCD()//打印CD
{
System.out.println("printCD over1");
CD getcd = new CD();
for(int i=0;i<vec.size();i++)
{
getcd = (CD) vec.elementAt(i);
System.out.println("ID:"+getcd.cdid+"\tName: "+getcd.cdname+"\tPrice: "+getcd.price+"\tPress: "+getcd.press);
}
System.out.println("printCD over2");
}
}
//输入信息的一个类
class MainInput
{
public String inputstr()
{
String pm = "";
try
{
InputStreamReader reader = new InputStreamReader(System.in);
BufferedReader input = new BufferedReader(reader);
pm = input.readLine();
}
catch (IOException e)
{
System.out.println("IO Exception occur...");
}
return pm;
}
public void input(CDManager cm)
{
int gate=0;//接收输入的选项
String str;//接收输入的字符串
float flo;//接收输入的价格
CD getcd = new CD();
int count = 0;
System.out.println("---------------Welcome to Media Manage System---------------");
lab_wl: while(true)
{
count++;
System.out.println("1. add CD");
System.out.println("2. find CD by ID");
System.out.println("3. remove CD by ID");
System.out.println("0. exit system");
System.out.println("Enter your choose: ");
try
{
gate = Integer.parseInt(inputstr());
}
catch (NumberFormatException e)
{
System.out.println("invalid data format...");
}
switch(gate)
{
case 1:
System.out.println("Enter CD ID: ");
str = inputstr();
getcd.cdid = str;
System.out.println("Enter cd name: ");
str = inputstr();
getcd.cdname = str;
while(true)
{//此循环用于保证输入float错误可以重新输入
System.out.println("Enter price: ");
try
{
flo = Float.parseFloat(inputstr());
getcd.price = flo;
break;
}
catch (NumberFormatException e)
{
System.out.println("invalid data format...");
}
}
System.out.println("Enter press: ");
str = inputstr();
getcd.press = str;
cm.addCD(getcd);
//以下为测试代码段，用于测试数据是否正确存入cm.vec
System.out.println("\n======1=======\n");
CD getcds = new CD();
System.out.println(cm.vec.size());
for(int i=0;i<cm.vec.size();i++)
{
getcds = (CD) cm.vec.elementAt(i);
System.out.println("ID:"+getcds.cdid+"\tName: "+getcds.cdname+"\tPrice: "+getcds.price+"\tPress: "+getcds.press);
}
System.out.println("\n=========2=========\n");
//测试结束
break;
case 0:
break lab_wl;
default: break;
}//end of switch
}//end of while
}
}
class MyMediaDemo
{
public static void main(String[] args)
{
CDManager cm = new CDManager();
MainInput mi = new MainInput();
mi.input(cm);
//cm.printCD();
}
}

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