Question

所以我正在为rss程序编写一些代码，但是我的代码找不到问题。我有4个问题，当我观看视频时，它看上去完全一样。请帮我。先感谢您。这是错误，

Main.java:27: error: illegal start of type
    } catch (MalformedURLException ue) {
      ^
Main.java:29: error: illegal start of type
    } catch (IOException ioe) {
      ^
Main.java:32: error: illegal start of type
    return null;
    ^
Main.java:32: error: ';' expected
    return null;
          ^
Main.java:35: error: class, interface, or enum expected
}
^
5 errors

我研究了几个不同线程上的堆栈溢出，但是没有任何信息有用。我删除了花括号，添加了花括号，添加了分号，没有任何效果

     import java.io.*;
import java.net.*;
public class RSSReader {
    public static void Main(String[] args) {
    System.out.printIn(ReadRSS("https://www.oracle.com/technetwork/topics/newtojava/overview/index.html/pageslug?format=rss"));

    }

    public static String readRSS(String urlAddress) {

       URL rssUrl = new URL(urlAddress);
       BufferedReader in = new BufferedReader(new InputStreamReader(rssUrl.openStream()));
       String sourceCode = "";
       String line;
       while((line = in.readLine())!=null) {
           if (line.contains("<title>")) {
               int firstPos = line.indexOf("<title>");
               String temp = line.substring(firstPos);
               temp = temp.replace("<title>", "");
               int lastPos = temp.indexOf("</title>");
               temp = temp.substring(0, lastPos);
               sourceCode += temp+"\n";
           }
       }
       in.close();
      return sourceCode;
    } catch (MalformedURLException ue) {
        System.out.printIn("Malformed URL");
    } catch (IOException ioe) {
        System.out.printIn("Something went wrong reading the contents");
    }
    return null;

    }
}

Answer 1

通常，此错误表示您在闭合括号}上放错了位置。在这种情况下，您将缺少try {和catch一起使用的public static class ServiceCollectionExt { public static void AddSingleton<I1, I2, T>(this IServiceCollection services) where T : class, I1, I2 where I1 : class where I2 : class { services.AddSingleton<I1, T>(); services.AddSingleton<I2, T>(x => (T) x.GetService<I1>()); } }（注意开头括号）。

Answer 2

缺少尝试{

和System.out.printIn错误，应该是System.out.println

import java.io.*;
import java.net.*;

public class RSSReader {
    public static void Main(String[] args) {
        System.out.printIn(
                ReadRSS("https://www.oracle.com/technetwork/topics/newtojava/overview/index.html/pageslug?format=rss"));

    }

    public static String readRSS(String urlAddress) {
        try {
            URL rssUrl = new URL(urlAddress);
            BufferedReader in = new BufferedReader(new InputStreamReader(rssUrl.openStream()));
            String sourceCode = "";
            String line;

            while ((line = in.readLine()) != null) {
                if (line.contains("<title>")) {
                    int firstPos = line.indexOf("<title>");
                    String temp = line.substring(firstPos);
                    temp = temp.replace("<title>", "");
                    int lastPos = temp.indexOf("</title>");
                    temp = temp.substring(0, lastPos);
                    sourceCode += temp + "\n";
                }
            }
            in.close();
            return sourceCode;
        } catch (MalformedURLException ue) {
            System.out.println("Malformed URL");
        } catch (IOException ioe) {
            System.out.println("Something went wrong reading the contents");
        }
        return null;

    }

}

带有捕获类型的非法开始

2 个答案: