在httpConn.connect（）中获取Excception; （代码的第5行）代码和执行错误如下所示..我试图将android应用程序连接到互联网..我从互联网获取此代码..但是它给出了异常......代码完全给出了bewlow..i已经添加了已经显示的权限 我不知道什么是te erroe
代码..
public class httpsData extends Activity {
ImageView img;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String str = DownloadText("http://www.edumobile.org/android/");
TextView txt = (TextView) findViewById(R.id.text);
txt.setText(str);
}
private String DownloadText(String URL)
{ Log.v("Wasim ","11");
int BUFFER_SIZE = 2000;
InputStream in = null;
try {
in = OpenHttpConnection(URL);
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
return "";
}
InputStreamReader isr = new InputStreamReader(in);
int charRead;
String str = "";
char[] inputBuffer = new char[BUFFER_SIZE];
try {
while ((charRead = isr.read(inputBuffer))>0)
{
//---convert the chars to a String---
String readString = String.copyValueOf(inputBuffer, 0, charRead);
str += readString;
inputBuffer = new char[BUFFER_SIZE];
}
in.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
return "";
}
return str;
}
private InputStream OpenHttpConnection(String urlString)
throws IOException
{
InputStream in = null;
int response = -1;
URL url = new URL(urlString);
URLConnection conn = url.openConnection();
if (!(conn instanceof HttpURLConnection))
{
throw new IOException("Not an HTTP connection");
}
HttpURLConnection httpConn = (HttpURLConnection) conn;
httpConn.setAllowUserInteraction(false);
httpConn.setInstanceFollowRedirects(true);
httpConn.setRequestMethod("GET");
httpConn.connect();
response = httpConn.getResponseCode();
if (response == HttpURLConnection.HTTP_OK) {
in = httpConn.getInputStream();
}
return in;
}
}
错误是这些：
12-04 14:57:34.947: E/AndroidRuntime(5851): FATAL EXCEPTION: main
12-04 14:57:34.947: E/AndroidRuntime(5851): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.apps.httpsData/com.apps.httpsData.httpsData}: android.os.NetworkOnMainThreadException
12-04 14:57:34.947: E/AndroidRuntime(5851): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
12-04 14:57:34.947: E/AndroidRuntime(5851): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
12-04 14:57:34.947: E/AndroidRuntime(5851): at android.app.ActivityThread.access$600(ActivityThread.java:130)
12-04 14:57:34.947: E/AndroidRuntime(5851): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
12-04 14:57:34.947: E/AndroidRuntime(5851): at android.os.Handler.dispatchMessage(Handler.java:99)
12-04 14:57:34.947: E/AndroidRuntime(5851): at android.os.Looper.loop(Looper.java:137)
12-04 14:57:34.947: E/AndroidRuntime(5851): at android.app.ActivityThread.main(ActivityThread.java:4745)
12-04 14:57:34.947: E/AndroidRuntime(5851): at java.lang.reflect.Method.invokeNative(Native Method)
12-04 14:57:34.947: E/AndroidRuntime(5851): at java.lang.reflect.Method.invoke(Method.java:511)
12-04 14:57:34.947: E/AndroidRuntime(5851): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
12-04 14:57:34.947: E/AndroidRuntime(5851): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
12-04 14:57:34.947: E/AndroidRuntime(5851): at dalvik.system.NativeStart.main(Native Method)
12-04 14:57:34.947: E/AndroidRuntime(5851): Caused by: android.os.NetworkOnMainThreadException
12-04 14:57:34.947: E/AndroidRuntime(5851): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1117)
12-04 14:57:34.947: E/AndroidRuntime(5851): at java.net.InetAddress.lookupHostByName(InetAddress.java:385)
12-04 14:57:34.947: E/AndroidRuntime(5851): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
12-04 14:57:34.947: E/AndroidRuntime(5851): at java.net.InetAddress.getAllByName(InetAddress.java:214)
12-04 14:57:34.947: E/AndroidRuntime(5851): at libcore.net.http.HttpConnection.<init>(HttpConnection.java:70)
12-04 14:57:34.947: E/AndroidRuntime(5851): at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
12-04 14:57:34.947: E/AndroidRuntime(5851): at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:341)
12-04 14:57:34.947: E/AndroidRuntime(5851): at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:87)
12-04 14:57:34.947: E/AndroidRuntime(5851): at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
12-04 14:57:34.947: E/AndroidRuntime(5851): at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:315)
12-04 14:57:34.947: E/AndroidRuntime(5851): at libcore.net.http.HttpEngine.connect(HttpEngine.java:310)
12-04 14:57:34.947: E/AndroidRuntime(5851): at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:289)
12-04 14:57:34.947: E/AndroidRuntime(5851): at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:239)
12-04 14:57:34.947: E/AndroidRuntime(5851): at libcore.net.http.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:80)
12-04 14:57:34.947: E/AndroidRuntime(5851): at com.apps.httpsData.httpsData.OpenHttpConnection(httpsData.java:97)
12-04 14:57:34.947: E/AndroidRuntime(5851): at com.apps.httpsData.httpsData.DownloadText(httpsData.java:42)
12-04 14:57:34.947: E/AndroidRuntime(5851): at com.apps.httpsData.httpsData.onCreate(httpsData.java:30)
12-04 14:57:34.947: E/AndroidRuntime(5851): at android.app.Activity.performCreate(Activity.java:5008)
12-04 14:57:34.947: E/AndroidRuntime(5851): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
12-04 14:57:34.947: E/AndroidRuntime(5851): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)
12-04 14:57:34.947: E/AndroidRuntime(5851): ... 11 more
答案 0 :(得分：4)
您无法在主线程上执行HTTP连接请求。
使用Async Task并在doInBackground()方法中执行http请求。
答案 1 :(得分：0)
为此必须使用异步任务。要执行Server类，请在您希望调用HTTP CONNECTION的方法中使用这些代码----------- 服务器downloadFile = new Server（）; downloadFile.execute（）;
class Server extends AsyncTask<String, Integer, String> {
@Override
protected String doInBackground(String... arg0) {
// TODO Auto-generated method stub
try{
ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
HttpClient httpclient = new DefaultHttpClient();
//link
String adad="http://"+iP+"/"+faCility+"/distt.php";
HttpPost httppost = new HttpPost(adad);
nameValuePairs.add(new BasicNameValuePair(uSername,pAssword));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
response = httpclient.execute(httppost);
if(response !=null)
{
HttpEntity entityy = response.getEntity();
is = entityy.getContent();
}
}catch(Exception e){
Log.e("log_tag", "Error in http connection"+e.toString());
}
//convert response to string
if(is !=null){
try{//StringBuilder sb = new StringBuilder();
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
System.out.println("66666666666666");
//todo your work here with "is"
sb = new StringBuilder();
sb.append(reader.readLine() + "\n");
System.out.println("77777777777");
String line="0";
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
System.out.println("88888888888888");
System.out.println(sb);
result=sb.toString();
System.out.println("---------------------------------"+result+"---------------------");
System.out.println("9999999999999999999");
}catch(Exception e){
Log.e("log_tag", "Error converting result "+e.toString());
}
}
return result;
}
protected void onPostExecute(String resultt)
{
}
}
答案 2 :(得分：0)
试试这个..
TextView txt;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
txt = (TextView) findViewById(R.id.text);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB)
new DownloadText("http://www.edumobile.org/android/").executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, new String[]{null});
else
new DownloadText("http://www.edumobile.org/android/").execute(new String[]{null});
}
public class DownloadText extends AsyncTask<String, Void, String> {
// variables passed in:
String urls;
// constructor
public DownloadText(String urls) {
this.urls = urls;
}
@Override
protected void onPreExecute() {
pDialog = ProgressDialog.show(httpsData.this, "Fetching Details..", "Please wait...", true);
}
@Override
protected String doInBackground(String... params) {
// TODO Auto-generated method stub
int BUFFER_SIZE = 2000;
InputStream in = null;
try {
InputStream in = null;
int response = -1;
URL url = new URL(urls);
URLConnection conn = url.openConnection();
if (!(conn instanceof HttpURLConnection))
{
throw new IOException("Not an HTTP connection");
}
HttpURLConnection httpConn = (HttpURLConnection) conn;
httpConn.setAllowUserInteraction(false);
httpConn.setInstanceFollowRedirects(true);
httpConn.setRequestMethod("GET");
httpConn.connect();
response = httpConn.getResponseCode();
if (response == HttpURLConnection.HTTP_OK) {
in = httpConn.getInputStream();
}
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
return "";
}
InputStreamReader isr = new InputStreamReader(in);
int charRead;
String str = "";
char[] inputBuffer = new char[BUFFER_SIZE];
try {
while ((charRead = isr.read(inputBuffer))>0)
{
//---convert the chars to a String---
String readString = String.copyValueOf(inputBuffer, 0, charRead);
str += readString;
inputBuffer = new char[BUFFER_SIZE];
}
in.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
return "";
}
}
@Override
protected void onPostExecute(String result) {
// Now we have your JSONObject, play around with it.
if (pDialog.isShowing())
pDialog.dismiss();
if(!result.equals(""))
txt.setText(result);
}
}