import java.io.*;
public class CCar
{
public class car1 // 基类
{

car1(String tap)
{
if(tap=="big")
System.out.println("this call number is:45656798");
if(tap=="mid")
System.out.println("this call number is:5667800");
if(tap=="lit")
System.out.println("this call number is:23454665");
}
}

public class bigcar extends car1 // 大车
{
bigcar()
{ car1 client=new car1("big");
System.out.println("rent="+300);

}
}

public class midcar extends car1 // 中车
{
midcar()
{ car1 client=new car1("mid");
System.out.println("rent="+400);

}
}

public class litcar extends car1 // 小车
{
litcar()
{ car1("lit");
System.out.println("rent="+500);

}
}

public static void main(String[]args) throws IOException // 主函数
{

BufferedReader buf=new BufferedReader(new InputStreamReader(System.in));
String a;
a=buf.readLine();
if(a=="big")
bigcar();
if(a=="mid")
midcar();
if(a=="lit")
litcar();
}
}
　　我想用继承的方法　来输出　　大中小汽车的价格和　　电话．．
　请各位帮我改下ＯＫ？

import java.io.*;
import java.lang.*;
public class CCar
{
public class car1 // 基类
{
String tap;

car1(String tap)
{
if(this.tap=="big")
System.out.println("this call number is:45656798");
if(this.tap=="mid")
System.out.println("this call number is:5667800");
if(this.tap=="lit")
System.out.println("this call number is:23454665");
}
}

public class bigcar extends car1 // 大车
{
bigcar(String tap)
{ super(tap);
System.out.println("rent="+300);

}
}

public class midcar extends car1 // 中车
{
midcar(String tap)
{ super(tap);
System.out.println("rent="+400);

}
}

public class litcar extends car1 // 小车
{
litcar(String tap)
{ super(tap);
System.out.println("rent="+500);

}
}

public static void main(String[] args) throws IOException // 主函数
{
car1 client;
bigcar client1;
midcar client2;
litcar clietn3;
BufferedReader buf=new BufferedReader(new InputStreamReader(System.in));
String a;
a=buf.readLine();
if(a=="big")
client1=new bigcar(a);
if(a=="mid")
client2=new midcar(a);
if(a=="lit")
client3=new litcar(a);
}

｝
我改了下．．但是还是抱错．．　各位看一下呀。