Question

我想从Android应用程序向JSP页面发送一些值。我尝试了下面的代码。

在android中，Register.Java

 Register.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            try {
                ArrayList<BasicNameValuePair> namevaluepair = new ArrayList<BasicNameValuePair>();
                namevaluepair.add(new BasicNameValuePair("fname", fname = UserFname.getText().toString()));
                namevaluepair.add(new BasicNameValuePair("lname", laname = UserLname.getText().toString()));
                namevaluepair.add(new BasicNameValuePair("uname", uname = Username.getText().toString()));
                namevaluepair.add(new BasicNameValuePair("pwd", pwd = UserPassword.getText().toString()));
                namevaluepair.add(new BasicNameValuePair("dob", udob = UserDob.getText().toString()));
                namevaluepair.add(new BasicNameValuePair("email", uemail = UserEmailId.getText().toString()));
                namevaluepair.add(new BasicNameValuePair("mob", umobno = UserMobileNo.getText().toString()));
                HttpClient client = new DefaultHttpClient();
                Log.e("hi ","check");
                HttpPost post=new HttpPost("http://10.0.0.2:8080/AndroidConnectivity/index.jsp");
                Log.e("hi ","check1");
                post.setEntity(new UrlEncodedFormEntity(namevaluepair));
                Log.e("hi ","check2");
                HttpResponse response= client.execute(post);
                Log.e("hi ","check3");
                HttpEntity entity=response.getEntity();
                Log.e("hi ","check4");

            }catch (Exception e){
                Log.e("Error while",e.toString());
            }

        }
    });

在JSP中，index.jsp

    <% 

        String fnmae= request.getParameter("fname");
        String lname= request.getParameter("lname");
        String unmae = request.getParameter("uname");
        String pwd=request.getParameter("pwd");
        String dob =request.getParameter("dob");
        String email =request.getParameter("email");
        String mob =request.getParameter("mob");

        DBConnection obj = new DBConnection();
            obj.setResultValueUpdate("insert into user_master (f_name,l_name,user_name,password,dob,email_id,contact_no) values ('"+ fnmae +"', '"+ lname +"','"+ unmae +"','"+ pwd +"','"+ dob +"', '"+ email +"','"+ mob +"')");
            obj.getUpdate();
    %>

当我点击“注册”按钮时，出现此错误：

E / Error while：org.apache.http.conn.HttpHostConnectException：与http://10.0.0.2:8080的连接被拒绝

我尝试了 HttpPost 中的所有可能组合，例如我的笔记本电脑IP地址或 127.0.0.1 ，但我收到同样的错误。< / p>

Logcat正在显示：

 Log.e("hi ","check3");

之后我收到了一个错误。我该怎么做这个任务？

Answer 1

异步任务：

package com.abc.webservice;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;

import android.annotation.SuppressLint;
import android.annotation.TargetApi;
import android.app.ProgressDialog;
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.AsyncTask;
import android.os.Build;
import android.os.StrictMode;
import android.util.Log;


public class GetData_AsyncTask extends AsyncTask<String, Void, String> 
{
String result="";
Context context;
String params[];

String baseDomainURL = "http://192.168.1.109:8080/";
String jspPath;

public GetData_AsyncTask(Context context, String...params)
{
    this.context = context;
    this.params = params;
}


private ProgressDialog progDialog;        

@Override
protected void onPreExecute() 
{
    super.onPreExecute(); 
    //progDialog = ProgressDialog.show(context, "HTTP Request", "please wait.." , true, false);
}


@Override        
protected String doInBackground(String... notneeded) 
{   
    // SELECT JSP
    if(Integer.parseInt(this.params[0])==1)
    {
        jspPath = "abc.jsp";
    }
    else if(Integer.parseInt(this.params[0])==2)
    {
        jspPath = "def.jsp";
    }

    // CREATE HTTP PARAMS
    String httpParameters = "no=" + Integer.parseInt(this.params[1]) + "&name=" + this.params[2];


    // CREATE REQUEST URL
    String requestURL = baseDomainURL + "/" + jspPath + "?" + httpParameters;


    // CHECK INTERNET CONNECTION & MAKE HTTP REQUEST
    if(hasConnection(this.context))
    {
        try 
        {    
            this.result = getDataFromServer1(requestURL);
            //this.result = getDataFromServer2(requestURL);
            //this.result = getDataFromServer3(requestURL);

            Log.e("async", "HTTP Request Successful: Response: "+this.result);
        }

        catch (Exception e) 
        {
            Log.d("async", "in AsyncTask; Error: "+e.getMessage());
            e.printStackTrace();
        }
    }
    return null;
}



@Override        
protected void onPostExecute(String result) 
{

    // POST HTTP REQUEST EXECUTION

    // DISMISS DIALOG
    //progDialog.dismiss();

}    





//CHECK INTERNET CONNECTION
public static boolean hasConnection(Context context) 
{
    ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo netInfo = cm.getActiveNetworkInfo();
    if (netInfo != null && netInfo.isConnected()) 
    {
        return true;
    }
    return false;
}



@TargetApi(Build.VERSION_CODES.GINGERBREAD)
@SuppressLint("NewApi")
private String getDataFromServer1(String url_arg) 
{
    String result ="";
    try 
    {
        StrictMode.ThreadPolicy policy = new StrictMode.
          ThreadPolicy.Builder().permitAll().build();
        StrictMode.setThreadPolicy(policy); 
        URL url = new URL(url_arg);
        HttpURLConnection con = (HttpURLConnection) url.openConnection();
        result = readStream(con.getInputStream());
    } catch (Exception e) {
        e.printStackTrace();
    }
    return result;
}

private String readStream(InputStream in) 
{
  BufferedReader reader = null;
  try 
  {
    reader = new BufferedReader(new InputStreamReader(in));
    String line = "";
    String result="";
    while ((line = reader.readLine()) != null) 
    {
     // System.out.println(line);
        result = result+line;
    }
  } 
  catch (IOException e) 
  {
    e.printStackTrace();
  } 
  finally 
  {
    if (reader != null) 
    {
      try 
      {
        reader.close();
      } 
      catch (IOException e) 
      {
        e.printStackTrace();
      }
    }
  }
  return result;
}




private String getDataFromServer2(String url_arg) 
{
    String page = "";
     try 
     {
         URL url = new URL(url_arg);
         BufferedReader in =  new BufferedReader(new InputStreamReader(url.openStream()));

        String inLine;


            while ((inLine = in.readLine()) != null) 
            {
                page += inLine;
            }


        in.close();
     } 

     catch (IOException e) 
     {
            e.printStackTrace();
            Log.d("async","Problem connecting to the server: "+e.getMessage());
            Log.d("async","Problem connecting to the server: "+e.getLocalizedMessage());
            Log.d("async","Problem connecting to the server: "+e.getCause());
            Log.d("async","Problem connecting to the server: "+e.getStackTrace());
     }
     catch (Exception e) 
     {
        e.printStackTrace();
        Log.d("async","Problem connecting to the server: "+e.getMessage());
        Log.d("async","Problem connecting to the server: "+e.getLocalizedMessage());
        Log.d("async","Problem connecting to the server: "+e.getCause());
        Log.d("async","Problem connecting to the server: "+e.getStackTrace());
     }
     return page;
}




private String getDataFromServer3(String url)
{
    URL url2=null;

    try
    {
        url2 = new URL(url);
    }

    catch (MalformedURLException e1)
    {
        e1.printStackTrace();
    }

    URLConnection con=null;

    try
    {
        con = url2.openConnection();
    }

    catch (IOException e1)
    {
      e1.printStackTrace();
      return "";
    }
    catch (Exception e1)
    {
      e1.printStackTrace();
      return "";
    }

    con.setRequestProperty("User-Agent", "Mozilla/5.0");

    Reader r = null;

    try
    {
        r = new InputStreamReader(con.getInputStream());
    }

    catch (IOException e)
    {
      e.printStackTrace();
      return "";
    }
    catch(Exception e)
    {
          e.printStackTrace();
          return "";
    }

    StringBuilder buf = new StringBuilder();

    int ch=0;

    while (true)
    {
        try
        {
            ch = r.read(); 
        }

        catch (NullPointerException e)
        {
          e.printStackTrace();  
          Log.e("HTML Response Error", "NullpointerException:" + e.getMessage());
          return "";
        }
        catch (RuntimeException e)
        {
          e.printStackTrace();
          Log.e("HTML Response Error", "RuntimeException:" + e.getMessage());
          return "";
        }
        catch (IOException e)
        {
          e.printStackTrace();
          Log.e("HTML Response Error", "IOException:" + e.getMessage());
          return "";
        }
        catch(Exception e)
        {
            e.printStackTrace();
            Log.e("HTML Response Error", "Exception:" + e.getMessage());
            return "";
        }

        if (ch < 0)
          break;

        buf.append((char) ch);

    }

    String str = buf.toString();


    Log.d("HTML Response", str);
    return str;
}

}

调用异步任务：

// PREPARE PARAMETERS
String[] params = new String[10];
params[0] = "1";
params[1] = "1";
params[2] = "abc";


// NEW ASYNC TASK 
new GetData_AsyncTask(getActivity(), params).execute();

将这些添加到Manifest：

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Answer 2

NetworkOnMainThreadException。您无法在主Android线程上执行网络任务。主线程是为UI保留的，您必须创建一个新的异步任务。

How to fix android.os.NetworkOnMainThreadException? StackOverflow / Android中最受欢迎的问题

如何从Android应用程序发送数据到JSP？

2 个答案: