Question

我正在尝试从URL连接中读取HTML代码。在一个案例中，我正在尝试阅读的html文件在实际的doc类型声明之前包含5个换行符。在这种情况下，输入阅读器会抛出EOF异常。

URL pageUrl = 
    new URL(
        "http://www.nytimes.com/2011/03/15/sports/basketball/15nbaround.html"
    );

URLConnection getConn = pageUrl.openConnection();
getConn.connect();
DataInputStream dis = new DataInputStream(getConn.getInputStream());
//some read method here

有没有人遇到这样的问题？

URL pageUrl = new URL("http://www.nytimes.com/2011/03/15/sports/basketball/15nbaround.html");
URLConnection getConn = pageUrl.openConnection();
getConn.connect();
DataInputStream dis = new DataInputStream(getConn.getInputStream());
String urlData = "";
while ((urlData = dis.readUTF()) != null)
    System.out.println(urlData);

//抛出异常

java.io.EOFException的 at java.io.DataInputStream.readUnsignedShort（DataInputStream.java:323）在java.io.DataInputStream.readUTF（DataInputStream.java:572）在java.io.DataInputStream.readUTF（DataInputStream.java:547）

在bufferedreader的情况下，它只响应null并且不继续

pageUrl = new URL("http://www.nytimes.com/2011/03/15/sports/basketball/15nbaround.html");
URLConnection getConn = pageUrl.openConnection();
getConn.connect();
BufferedReader br = new BufferedReader(new InputStreamReader(getConn.getInputStream()));
String urlData = "";
while(true)
     urlData = br.readLine();
     System.out.println(urlData);

输出null

Answer 1

您正在使用DataInputStream来读取未使用DataOutputStream编码的数据。检查您DataInputStream#readUtf()号召唤的记录行为; it first reads two bytes形成一个16位整数，表示包含UTF编码字符串的后续字节数。您从HTTP服务器读取的数据不是以这种格式编码的。

相反，HTTP服务器按照RFC 2616部分6.1和2.2发送以ASCII编码的标头。您需要将标题读作文本，然后确定邮件正文（“实体”）的编码方式。

Answer 2

这很好用：

package url;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URL;

/**
 * UrlReader
 * @author Michael
 * @since 3/20/11
 */
public class UrlReader
{

    public static void main(String[] args)
    {
        UrlReader urlReader = new UrlReader();

        for (String url : args)
        {
            try
            {
                String contents = urlReader.readContents(url);
                System.out.printf("url: %s contents: %s\n", url, contents);
            }
            catch (Exception e)
            {
                e.printStackTrace();
            }
        }
    }


    public String readContents(String address) throws IOException
    {
        StringBuilder contents = new StringBuilder(2048);
        BufferedReader br = null;

        try
        {
            URL url = new URL(address);
            br = new BufferedReader(new InputStreamReader(url.openStream()));
            String line = "";
            while (line != null)
            {
                line = br.readLine();
                contents.append(line);
            }
        }
        finally
        {
            close(br);
        }

        return contents.toString();
    }

    private static void close(Reader br)
    {
        try
        {
            if (br != null)
            {
                br.close();
            }
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }
}

Answer 3

此：

public class Main {
    public static void main(String[] args) 
        throws MalformedURLException, IOException 
    {
        URL pageUrl = new URL("http://www.google.com");
        URLConnection getConn = pageUrl.openConnection();
        getConn.connect();
        BufferedReader dis = new BufferedReader( 
                                 new InputStreamReader(
                                     getConn.getInputStream()));
        String myString;
        while ((myString = dis.readLine()) != null)
        {
            System.out.println(myString);
        }
    }
}

完美无缺。但是，您提供的URL不会返回任何内容。

从URL连接Java读取

3 个答案: