java - 未报告的异常 java.io.ioexception 必须被捕获或声明为抛出

Question

这个编译错误是什么意思，我该如何解决？编译器将错误指向第 86 行

final PiFace piface = new PiFaceDevice(PiFace.DEFAULT_ADDRESS, Spi.CHANNEL_0);

告诉我

unreported exception java.io.ioexception must be caught or declared to be thrown

是不是跟需要try/catch有关？这是我从搜索中找到的最佳答案，但我不太确定如何实现它，我尝试了一下，结果产生了更多错误(您可以看到它已被注释掉)。

完整代码如下:

public class Relay1 extends javax.swing.JFrame {

    public Relay1() {
        initComponents();
    }

    private void initComponents() {
        // stuff that doesn't matter...
    }


    //try{
        final PiFace piface = new PiFaceDevice(PiFace.DEFAULT_ADDRESS, Spi.CHANNEL_0);
    //}catch(IOException e){
        //System.out.println("Something went wrong...");
    //}


    public static void main(String args[]) throws InterruptedException, IOException {        
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(Relay1.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(Relay1.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(Relay1.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(Relay1.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new Relay1().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify//GEN-BEGIN:variables
    private javax.swing.JButton jButton1;
    private javax.swing.JButton jButton2;
    // End of variables declaration//GEN-END:variables
}

Answer 1

您确实没有任何处理代码可以为您检查的异常提供。如果该异常只传播到调用者，这是完全可以接受的，在本例中是写入 new Relay1() 的地方。为此，编写如下:

final PiFace piface; { 
  try {
    piface = new PiFaceDevice(PiFace.DEFAULT_ADDRESS, Spi.CHANNEL_0);
  } catch(IOException e) { 
    throw new RuntimeException("Failed to create Pi Face Device", e); 
  }
}

这将使您既可以在异常中保留诊断信息，又可以满足编译器的要求。