import java.lang.*; 
class Car{ 
public void safe(){ 
System.out.println("an quan xi shu gao !"); 
} 
} 
class Benz extends Car{ 
public void safe(){ 
System.out.println("che hao !"); 
} 
} 
class Santana extends Car{ 
public void safe(){ 
System.out.println("che hen bu hao hao !"); 
} 
} 
public class Test{ 
public static void main(String[]args){ 
Car s = new Car(); 
s.safe(); 
Benz s1 = new Benz(); 
s1.safe(); 
Santana s2 = new Santana(); 
s2.safe(); 
Car s3 = new Benz(); 
s3.safe(); 
Car s4 = new Santana(); 
s4.safe(); 

} 
} 
這是一個 命名為Test.java 
public class Car{ 
double price; 
String name; 
int id; 

//3個重載的構造方法(name)(id,name)(id,name,price) 
public Car(String name){ 
this(789,name); 
} 
public Car(int id,String name){ 
this(id,name,100000); 
} 
protected Car(int id,String name,double price){ 
this.price = price; 
this.name = name; 
this.id = id; 
} 

//3個重載的普通方法drive(int) drive(String) drive(int ,String) 
public void drive(int i){ 
System.out.println("i = " + i); 
System.out.println(price + "\n" + name + "\n" + id); 
} 
protected String drive(String s){ 
return "s is: " + s; 
} 
int drive(int i,String s){ 
return 2007; 
} 
} 
class Test{ 
public static void main(String[]args){ 
Car c1 = new Car(777,"Santana"); 
c1.drive(18); 

} 
}