为什么我已经抛出未报告的异常 java.net.MalformedURLException？

Question

免责声明：我很久没有做过 Java。

我创建了这个 singleton class 来创建一个 HttpURLConnection。

public class EstablishConnection {
    HttpURLConnection conn = setupConn("some url");
    private static final EstablishConnection instance = new EstablishConnection();
    
    //private constructor to avoid client applications to use constructor
    private EstablishConnection(){}
​
    public static EstablishConnection getInstance(){
        return instance;
    }
    
    private static HttpURLConnection setupConn(String addr) throws MalformedURLException, IOException, ProtocolException {
        URL url = new URL(addr);
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setReadTimeout(10000);
        conn.setConnectTimeout(15000);
        conn.setRequestMethod("POST");
        conn.setDoInput(true);
        conn.setDoOutput(true);
        return conn;
    }
}
​

为什么我在setupConn中抛出未报告的MalformedURLException异常？

|       HttpURLConnection conn = setupConn("some url");
unreported exception java.net.MalformedURLException; must be caught or declared to be thrown

Answer 1

您正在从 setupConn function 抛出异常，但在此处调用它时您没有处理抛出的异常：

HttpURLConnection conn = setupConn("some url");

您可以使用 setupConn function 中的 try catch 处理异常，或者您可以在构造函数中调用 function 然后从那里重新抛出。