Question

Java编程Scanner读取text文件问题？

text.txt文件格式如下：
1.1 1.2 1.3 1.4 lineone
2.1 2.1 2.3 2.4 linetwo
...
Java中Scanner类基于行与标记的混合处理程序
File file = new File("C:/text.txt");
Scanner input = new Scanner(file);
while (input.hasNextLine()) {
String text = input.nextLine();
System.out.println(text);
Scanner data = new Scanner(text);
for (int i = 0; i < 4; i++) {
double vector = data.nextDouble();
System.out.println(vector);
}
System.out.println(data.next());
}
运行后在double vector = data.nextDouble();行抛出异常java.util.NoSuchElementException
请问高手，程序有什么问题？怎么解决？多谢了！

Answer 1

改成这样的：
import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

public class Scan {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
File file = new File("C:/text.txt");
Scanner input = null;
try {
input = new Scanner(file);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
while (input.hasNextLine()) {
String text = input.nextLine();
System.out.println(text);
Scanner data = new Scanner(text);
for (int i = 0; i < 4; i++) {
double vector = data.nextDouble();
System.out.println(vector);
}
System.out.println(data.next());
}

}

}
运行结果为：
1.1 1.2 1.3 1.4 lineone
1.1
1.2
1.3
1.4
lineone
2.1 2.1 2.3 2.4 linetwo

Answer 2

NoSuchElementException表示元素类型不匹配，你检查下是不是输入的数据不是double类型的或者是在其他地方出现了类型错误

Answer 3

判断条件不对
Scanner data = new Scanner(text); 这个是干什么的????

下面的是可用的
input = new Scanner(file);
while (input.hasNext()) {
System.out.println(input.next());
}