I am trying to understand the basic get method in android. I run the following code . But getting a runtime exception. I am not able to understand where exactly the error lies.
MyHttpGetProjectActivity.java
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MyHttpGetProjectActivity extends Activity implements OnClickListener {
private EditText usernameEditText;
private EditText passwordEditText;
private Button sendGetReqButton;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
usernameEditText = (EditText) findViewById(R.id.e1);
passwordEditText = (EditText) findViewById(R.id.e2);
sendGetReqButton = (Button) findViewById(R.id.b1);
sendGetReqButton.setOnClickListener(this);
}
@Override
public void onClick(View v) {
if(v.getId() == R.id.b1){
// Get the values given in EditText fields
String givenUsername = usernameEditText.getText().toString();
String givenPassword = passwordEditText.getText().toString();
System.out.println("Given usernames is :" + givenUsername + " Given password is :" + givenPassword);
// Pass those values to connectWithHttpGet() method
connectWithHttpGet(givenUsername, givenPassword);
}
}
private void connectWithHttpGet(String givenUsername, String givenPassword) {
// Connect with a server is a time consuming process.
//Therefore we use AsyncTask to handle it
// From the three generic types;
//First type relate with the argument send in execute()
//Second type relate with onProgressUpdate method which I haven't use in this code
//Third type relate with the return type of the doInBackground method, which also the input type of the onPostExecute method
class HttpGetAsyncTask extends AsyncTask<String, Void, String>{
@Override
protected String doInBackground(String... params) {
// As you can see, doInBackground has taken an Array of Strings as the argument
//We need to specifically get the givenUsername and givenPassword
String paramUsername = params[0];
String paramPassword = params[1];
System.out.println("paramUsername is :" + paramUsername + " paramPassword is :" + paramPassword);
// Create an intermediate to connect with the Internet
HttpClient httpClient = new DefaultHttpClient();
// Sending a GET request to the web page that we want
// Because of we are sending a GET request, we have to pass the values through the URL
HttpGet httpGet = new HttpGet("http://www.nirmana.lk/hec/android/getLogin.php?paramUsername=" + paramUsername + "¶mPassword=" + paramPassword);
try {
// execute(); executes a request using the default context.
// Then we assign the execution result to HttpResponse
HttpResponse httpResponse = httpClient.execute(httpGet);
System.out.println("httpResponse");
// getEntity() ; obtains the message entity of this response
// getContent() ; creates a new InputStream object of the entity.
// Now we need a readable source to read the byte stream that comes as the httpResponse
InputStream inputStream = httpResponse.getEntity().getContent();
// We have a byte stream. Next step is to convert it to a Character stream
InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
// Then we have to wraps the existing reader (InputStreamReader) and buffer the input
BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
// InputStreamReader contains a buffer of bytes read from the source stream and converts these into characters as needed.
//The buffer size is 8K
//Therefore we need a mechanism to append the separately coming chunks in to one String element
// We have to use a class that can handle modifiable sequence of characters for use in creating String
StringBuilder stringBuilder = new StringBuilder();
String bufferedStrChunk = null;
// There may be so many buffered chunks. We have to go through each and every chunk of characters
//and assign a each chunk to bufferedStrChunk String variable
//and append that value one by one to the stringBuilder
while((bufferedStrChunk = bufferedReader.readLine()) != null){
stringBuilder.append(bufferedStrChunk);
}
// Now we have the whole response as a String value.
//We return that value then the onPostExecute() can handle the content
System.out.println("Returning value of doInBackground :" + stringBuilder.toString());
// If the Username and Password match, it will return "working" as response
// If the Username or Password wrong, it will return "invalid" as response
return stringBuilder.toString();
} catch (ClientProtocolException cpe) {
System.out.println("Exception generates caz of httpResponse :" + cpe);
cpe.printStackTrace();
} catch (IOException ioe) {
System.out.println("Second exception generates caz of httpResponse :" + ioe);
ioe.printStackTrace();
}
return null;
}
// Argument comes for this method according to the return type of the doInBackground() and
//it is the third generic type of the AsyncTask
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
if(result.equals("working")){
Toast.makeText(getApplicationContext(), "HTTP GET is working...", Toast.LENGTH_LONG).show();
}else{
Toast.makeText(getApplicationContext(), "Invalid...", Toast.LENGTH_LONG).show();
}
}
}
// Initialize the AsyncTask class
HttpGetAsyncTask httpGetAsyncTask = new HttpGetAsyncTask();
// Parameter we pass in the execute() method is relate to the first generic type of the AsyncTask
// We are passing the connectWithHttpGet() method arguments to that
httpGetAsyncTask.execute(givenUsername, givenPassword);
}
}
Error:-
04-01 02:49:11.744: E/AndroidRuntime(1597): FATAL EXCEPTION: AsyncTask #1
04-01 02:49:11.744: E/AndroidRuntime(1597): Process: com.example.webservicedemo, PID: 1597
04-01 02:49:11.744: E/AndroidRuntime(1597): java.lang.RuntimeException: An error occured while executing doInBackground()
04-01 02:49:11.744: E/AndroidRuntime(1597): at android.os.AsyncTask$3.done(AsyncTask.java:300)
04-01 02:49:11.744: E/AndroidRuntime(1597): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
04-01 02:49:11.744: E/AndroidRuntime(1597): at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
04-01 02:49:11.744: E/AndroidRuntime(1597): at java.util.concurrent.FutureTask.run(FutureTask.java:242)
04-01 02:49:11.744: E/AndroidRuntime(1597): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
04-01 02:49:11.744: E/AndroidRuntime(1597): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
04-01 02:49:11.744: E/AndroidRuntime(1597): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
04-01 02:49:11.744: E/AndroidRuntime(1597): at java.lang.Thread.run(Thread.java:841)
04-01 02:49:11.744: E/AndroidRuntime(1597): Caused by: java.lang.SecurityException: Permission denied (missing INTERNET permission?)
04-01 02:49:11.744: E/AndroidRuntime(1597): at java.net.InetAddress.lookupHostByName(InetAddress.java:418)
04-01 02:49:11.744: E/AndroidRuntime(1597): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
04-01 02:49:11.744: E/AndroidRuntime(1597): at java.net.InetAddress.getAllByName(InetAddress.java:214)
04-01 02:49:11.744: E/AndroidRuntime(1597): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
04-01 02:49:11.744: E/AndroidRuntime(1597): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
04-01 02:49:11.744: E/AndroidRuntime(1597): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
04-01 02:49:11.744: E/AndroidRuntime(1597): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
04-01 02:49:11.744: E/AndroidRuntime(1597): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
04-01 02:49:11.744: E/AndroidRuntime(1597): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
04-01 02:49:11.744: E/AndroidRuntime(1597): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
04-01 02:49:11.744: E/AndroidRuntime(1597): at com.example.webservicedemo.MyHttpGetProjectActivity$1HttpGetAsyncTask.doInBackground(MyHttpGetProjectActivity.java:87)
04-01 02:49:11.744: E/AndroidRuntime(1597): at com.example.webservicedemo.MyHttpGetProjectActivity$1HttpGetAsyncTask.doInBackground(MyHttpGetProjectActivity.java:1)
04-01 02:49:11.744: E/AndroidRuntime(1597): at android.os.AsyncTask$2.call(AsyncTask.java:288)
04-01 02:49:11.744: E/AndroidRuntime(1597): at java.util.concurrent.FutureTask.run(FutureTask.java:237)
04-01 02:49:11.744: E/AndroidRuntime(1597): ... 4 more
04-01 02:49:11.744: E/AndroidRuntime(1597): Caused by: libcore.io.GaiException: getaddrinfo failed: EAI_NODATA (No address associated with hostname)
04-01 02:49:11.744: E/AndroidRuntime(1597): at libcore.io.Posix.getaddrinfo(Native Method)
04-01 02:49:11.744: E/AndroidRuntime(1597): at libcore.io.ForwardingOs.getaddrinfo(ForwardingOs.java:61)
04-01 02:49:11.744: E/AndroidRuntime(1597): at java.net.InetAddress.lookupHostByName(InetAddress.java:405)
04-01 02:49:11.744: E/AndroidRuntime(1597): ... 17 more
04-01 02:49:11.744: E/AndroidRuntime(1597): Caused by: libcore.io.ErrnoException: getaddrinfo failed: EACCES (Permission denied)
04-01 02:49:11.744: E/AndroidRuntime(1597): ... 20 more
