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HTTP Client in Apache return "Target host must not be null"

Posted on 2009-06-29
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Last Modified: 2013-12-06
Dear experts,
I am using Apache HTTP client library for Android emulator.
http://hc.apache.org/httpcomponents-client/httpclient/apidocs/org/apache/http/client/package-summary.html

However whenever I enter e.g "www.google.com" or "http://www.google.com", it always return error "Target host must not be null"
But when i convert into IP Address, all works well.
Would you be able to advice?

Thanks!
public void run() {

			Log.i("GList", "downloadProcess run()");

			props = new Properties();
 

			try {

				String url;

				url = "http://www.google.com"; //THIS IS FAILED

				//url = "http://216.239.61.104"; // THIS IS OK

				HttpManager.doGet(url, props);

			} catch (Exception e) {

				// TODO Auto-generated catch block

				e.printStackTrace();

			}

			// TODO Auto-generated method stub

		}

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Question by:isuhendro
  • 3
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5 Comments
 
LVL 86

Expert Comment

by:CEHJ
ID: 24743483
>>HttpManager.doGet(url, props);

What's that? It's not Apache HttpClient..
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Author Comment

by:isuhendro
ID: 24743532
Hi CEHJ,
HttpManager just a wrapper of Apache HTTP client, please refer to the static method inside HttpManager below.
	public static String doGet (String serviceEndpoint, Properties props) throws Exception

	{

		HttpClient httpClient = new DefaultHttpClient();

		StringBuilder uriBuilder = new StringBuilder(serviceEndpoint);

		StringBuffer sbResponse = new StringBuffer ();		

		Enumeration<Object> enumProps = props.keys();

		String key, value = null;

		

		if (enumProps.hasMoreElements()) uriBuilder.append('?');

		while (enumProps.hasMoreElements())

		{

			key = (String)enumProps.nextElement();

			value = (String)props.get(key);

			uriBuilder.append(key);

			uriBuilder.append('=');

			uriBuilder.append(java.net.URLEncoder.encode(value));

			uriBuilder.append('&');			

		}

		HttpGet request = new HttpGet(uriBuilder.toString());

		

	HttpResponse response = httpClient.execute(request);
 

		

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Accepted Solution

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CEHJ earned 125 total points
ID: 24743600
>>But when i convert into IP Address, all works well.

Sounds like a DNS error. Have you tried running your code on another network?
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Author Closing Comment

by:isuhendro
ID: 31598185
hi CEHJ,

thank you for your suggestion.
somehow this line java.net.URLEncoder gave invalid form URL
0
 
LVL 86

Expert Comment

by:CEHJ
ID: 24949148
:-)
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