java - 未报告的异常IOException…必须被捕获或声明为引发

Question

我收到此错误:在这段代码中:“未报告的异常IOException；必须被捕获或声明为抛出”:

 a = Double.parseDouble ( kb.readLine () ) ;
 b = Double.parseDouble ( kb.readLine () ) ;
 c = Double.parseDouble ( kb.readLine () ); 

这是其余的代码:

 package quadratic.java;


/**
 *
 * @author Painfulmono
 */
 import java.io.*;
 public class QuadraticDriver {

     BufferedReader kb = new BufferedReader 
                    (new InputStreamReader (System.in));
 public static void main (String [] args){

     double a, b, c;

     a = Double.parseDouble ( kb.readLine () ) ;
     b = Double.parseDouble ( kb.readLine () ) ;
     c = Double.parseDouble ( kb.readLine () ); 

     QuadraticJava q1 = new QuadraticJava (a, b, c);

     q1.solve();
}

}

我将如何声明它？

Answer 1

readLine()声明它抛出 IOException 。这是一个已检查的异常，这意味着您不能仅仅忽略它。您需要捕获它，例如:

try {
    a = Double.parseDouble ( kb.readLine () ) ;
} catch (IOException e) {
    System.out.println("Can't read a"); // Or something more intellegent
}

或者，如果您没有任何智能的方式来处理它，则可以通过将此异常添加到调用者的签名中来向上抛出它，例如:

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