How to convert the DataInputStream to the String in Java?

Question

I want to ask a question about Java. I have use the URLConnection in Java to retrieve the DataInputStream. and I want to convert the DataInputStream into a String variable in Java. What should I do? Can anyone help me. thank you.

The following is my code:

URL data = new URL("http://google.com");
URLConnection dataConnection = data.openConnection();
DataInputStream dis = new DataInputStream(dataConnection.getInputStream());
String data_string;
// convent the DataInputStream to the String

Answer 1

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

class ConnectionTest {
    public static void main(String[] args) {
        try {
            URL google = new URL("http://www.google.com/");
            URLConnection googleConnection = google.openConnection();
            DataInputStream dis = new DataInputStream(googleConnection.getInputStream());
            StringBuffer inputLine = new StringBuffer();
            String tmp; 
            while ((tmp = dis.readLine()) != null) {
                inputLine.append(tmp);
                System.out.println(tmp);
            }
            //use inputLine.toString(); here it would have whole source
            dis.close();
        } catch (MalformedURLException me) {
            System.out.println("MalformedURLException: " + me);
        } catch (IOException ioe) {
            System.out.println("IOException: " + ioe);
        }
    }
}  

This is what you want.

Answer 2

You can use commons-io IOUtils.toString(dataConnection.getInputStream(), encoding) in order to achieve your goal.

DataInputStream is not used for what you want - i.e. you want to read the content of a website as String.

Answer 3

If you want to read data from a generic URL (such as www.google.com), you probably don't want to use a DataInputStream at all. Instead, create a BufferedReader and read line by line with the readLine() method. Use the URLConnection.getContentType() field to find out the content's charset (you will need this in order to create your reader properly).

Example:

URL data = new URL("http://google.com");
URLConnection dataConnection = data.openConnection();

// Find out charset, default to ISO-8859-1 if unknown
String charset = "ISO-8859-1";
String contentType = dataConnection.getContentType();
if (contentType != null) {
    int pos = contentType.indexOf("charset=");
    if (pos != -1) {
        charset = contentType.substring(pos + "charset=".length());
    }
}

// Create reader and read string data
BufferedReader r = new BufferedReader(
        new InputStreamReader(dataConnection.getInputStream(), charset));
String content = "";
String line;
while ((line = r.readLine()) != null) {
    content += line + "\n";
}