菜鸟提问！

Question

public class BookDemo {
String name;
float price;
void output(){
System.out.println("name:"+name+"\t"+"price:"+price);
}
public static void main(String[] arg){
BookDemo b1;
b1=new BookDemo();
b1.output();
b1.name="java Programming";
b1.price=32.5f;
b1.output();
}　　　　　　 此行前有紅色小叉， 　} 下有紅色波浪線，运行提示如下：　　　　　　　　　　　
 }Exception in thread "main" java.lang.Error: Unresolved compilation problem: 
Syntax error, insert "}" to complete ClassBody at BookDemo.main(BookDemo.java:15)

Answer 1

public class BookDemo { 
String name; 
float price; 
void output(){ 
System.out.println("name:"+name+"\t"+"price:"+price); 
}
public static void main(String[] arg){ 
BookDemo b1; 
b1=new BookDemo(); 
b1.output();
b1.name="java Programming"; 
b1.price=32.5f;
b1.output(); 
}
}

Answer 2

public class BookDemo { 
String name; 
float price; 
void output(){ 
System.out.println("name:"+name+"\t"+"price:"+price); 
} 
public static void main(String[] arg){ 
BookDemo b1; 
b1=new BookDemo(); 
b1.output(); 
b1.name="java Programming"; 
b1.price=32.5f; 
b1.output(); 
}
} 

Answer 3

public class BookDemo {
String name;
float price; void output() {
System.out.println("name:" + name + "\t" + "price:" + price);
} public static void main(String[] arg) {
BookDemo b1 = new BookDemo();
b1.output();
b1.name = "java Programming";
b1.price = 32.5f;
b1.output();
}
}