Question

我一直在尝试遵循本教程：http://www.androidhive.info/2012/01/android-login-and-registration-with-php-mysql-and-sqlite/。它是创建一个Android登录应用程序。我已经阅读了评论，并没有明确回答出现此错误500服务器错误的原因以及如何解决它。

我研究了一个站点，建议将getJsonFromURL method放在AsyncTask中，因为它似乎在主线程上运行。但是，这并没有对服务器错误产生影响。

当下面的代码运行时，Logcat会读出内部服务器错误500.这意味着服务器无法理解发送给它的内容。我在JSONParser.java中注释掉了这一行：

 httpPost.setEntity(new UrlEncodedFormEntity(params));

并且该URL与服务器一起工作并获得200 ok服务器响应。

我只能假设处理名称值对的方式是错误的。但是，我发现的每个示例都使用List<NameValuePair>来收集登录的值具有与下面的代码相同的实现。

您能看一下下面的代码，或者向我建议另一种获取POST方法发送给服务器的名称值对的方法吗？

// JSONParser.java

package library;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONException;
import org.json.JSONObject;

import android.util.Log;

public class JSONParser {

    static InputStream is = null;
    static JSONObject jObj = null;
    static String json = "";

    // constructor
    public JSONParser() {

    }

    public JSONObject getJSONFromUrl(String url, List<NameValuePair> params) {

        // Making HTTP request
        try {
            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
            httpPost.setEntity(new UrlEncodedFormEntity(params));
            Log.v("name value pairs ",params.toString());

            HttpResponse httpResponse = httpClient.execute(httpPost);
            HttpEntity httpEntity = httpResponse.getEntity();
            Log.v("Http Response",httpResponse.getStatusLine().toString());
            is = httpEntity.getContent();

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    is, "iso-8859-1"), 8);
            StringBuilder sb = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null) {
                sb.append(line + "n");
            }
            is.close();
            json = sb.toString();
            Log.e("JSON", json);
        } catch (Exception e) {
            Log.e("Buffer Error", "Error converting result " + e.toString());
        }

        // try parse the string to a JSON object
        try {
            jObj = new JSONObject(json);
        } catch (JSONException e) {
            Log.e("JSON Parser", "Error parsing data " + e.toString());
        }

        // return JSON String
        return jObj;

    }
}

RegisterActivity.java：

package com.example.androidhive;

import org.json.JSONException;
import org.json.JSONObject;

import library.DatabaseHandler;
import library.UserFunctions;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class RegisterActivity extends Activity {
    Button btnRegister;
    Button btnLinkToLogin;
    EditText inputFullName;
    EditText inputEmail;
    EditText inputPassword;
    TextView registerErrorMsg;

    // JSON Response node names
    private static String KEY_SUCCESS = "success";
    private static String KEY_ERROR = "error";
    private static String KEY_ERROR_MSG = "error_msg";
    private static String KEY_UID = "uid";
    private static String KEY_NAME = "name";
    private static String KEY_EMAIL = "email";
    private static String KEY_CREATED_AT = "created_at";

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.register);

        // Importing all assets like buttons, text fields
        inputFullName = (EditText) findViewById(R.id.registerName);
        inputEmail = (EditText) findViewById(R.id.registerEmail);
        inputPassword = (EditText) findViewById(R.id.registerPassword);
        btnRegister = (Button) findViewById(R.id.btnRegister);
        btnLinkToLogin = (Button) findViewById(R.id.btnLinkToLoginScreen);
        registerErrorMsg = (TextView) findViewById(R.id.register_error);

        // Register Button Click event
        btnRegister.setOnClickListener(new View.OnClickListener() {
            public void onClick(View view) {
                String name = inputFullName.getText().toString();
                String email = inputEmail.getText().toString();
                String password = inputPassword.getText().toString();
                UserFunctions userFunction = new UserFunctions();
                JSONObject json = userFunction.registerUser(name, email, password);

                // check for login response
                try {
                    if (json.getString(KEY_SUCCESS) != null) {
                        registerErrorMsg.setText("");
                        String res = json.getString(KEY_SUCCESS);
                        if(Integer.parseInt(res) == 1){
                            // user successfully registred
                            // Store user details in SQLite Database
                            DatabaseHandler db = new DatabaseHandler(getApplicationContext());
                            JSONObject json_user = json.getJSONObject("user");

                            // Clear all previous data in database
                            userFunction.logoutUser(getApplicationContext());
                            db.addUser(json_user.getString(KEY_NAME), json_user.getString(KEY_EMAIL), json.getString(KEY_UID), json_user.getString(KEY_CREATED_AT));
                            // Launch Dashboard Screen
                            Intent dashboard = new Intent(getApplicationContext(), DashboardActivity.class);
                            // Close all views before launching Dashboard
                            dashboard.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                            startActivity(dashboard);
                            // Close Registration Screen
                            finish();
                        }else{
                            // Error in registration
                            registerErrorMsg.setText("Error occured in registration");
                        }
                    }
                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        });

        // Link to Login Screen
        btnLinkToLogin.setOnClickListener(new View.OnClickListener() {

            public void onClick(View view) {
                Intent i = new Intent(getApplicationContext(),
                        LoginActivity.class);
                startActivity(i);
                // Close Registration View
                finish();
            }
        });
    }
}

UserFunctions.java：

package library;

import java.util.ArrayList;
import java.util.List;

import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONObject;
import android.util.Log;
import android.content.Context;

public class UserFunctions {

    private JSONParser jsonParser;

    // Testing in Leobee.com
    // use http://10.0.2.2/ to connect to your localhost ie http://localhost/

    private static String loginURL = "http://www.leobee.com/android/push/login/";
    private static String registerURL = "http://www.leobee.com/android/push/login/index.php?";


    private static String login_tag = "login";
    private static String register_tag = "register";

    // constructor
    public UserFunctions(){
        jsonParser = new JSONParser();
    }

    /**
     * function make Login Request
     * @param email
     * @param password
     * */
    public JSONObject loginUser(String email, String password){
        // Building Parameters
        List<NameValuePair> params = new ArrayList<NameValuePair>();
        params.add(new BasicNameValuePair("tag", login_tag));
        params.add(new BasicNameValuePair("email", email));
        params.add(new BasicNameValuePair("password", password));
        JSONObject json = jsonParser.getJSONFromUrl(loginURL, params);
        // return json
        // Log.e("JSON", json.toString());
        return json;
    }

    /**
     * function make Login Request
     * @param name
     * @param email
     * @param password
     * */
    public JSONObject registerUser(String name, String email, String password){
        Log.v("register user", name+ "  "+email +" " + password);
        // Building Parameters
        ArrayList<NameValuePair> params = new ArrayList<NameValuePair>();
        params.add(new BasicNameValuePair("tag", register_tag));
        params.add(new BasicNameValuePair("name", name));
        params.add(new BasicNameValuePair("email", email));
        params.add(new BasicNameValuePair("password", password));

        // getting JSON Object
        Log.v("url placed in json object", registerURL);
       // Log.v("url placed in json object",  params);
        JSONObject json = jsonParser.getJSONFromUrl(registerURL, params);
        // return json
        Log.v("JSON parser string", json.toString());
        return json;
    }

    /**
     * Function get Login status
     * */
    public boolean isUserLoggedIn(Context context){
        DatabaseHandler db = new DatabaseHandler(context);
        int count = db.getRowCount();
        if(count > 0){
            // user logged in
            return true;
        }
        return false;
    }

    /**
     * Function to logout user
     * Reset Database
     * */
    public boolean logoutUser(Context context){
        DatabaseHandler db = new DatabaseHandler(context);
        db.resetTables();
        return true;
    }

}

使用名称值对记录cat 500错误：

05-27 05:47:07.342: V/register user(409): Name  email@email.com pass
05-27 05:47:07.353: V/url placed in json object(409): http://www.leobee.com/android/push/login/index.php?
05-27 05:47:07.362: V/name value pairs(409): [tag=register, name=Name, email=email@email.com, password=pass]
05-27 05:47:08.493: V/Http Response(409): HTTP/1.1 500 Internal Server Error
05-27 05:47:08.803: E/JSON Parser(409): Error parsing data org.json.JSONException: End of input at character 0 of 
05-27 05:47:08.803: D/AndroidRuntime(409): Shutting down VM
05-27 05:47:08.803: W/dalvikvm(409): threadid=1: thread exiting with uncaught exception (group=0x40015560)
05-27 05:47:08.824: E/AndroidRuntime(409): FATAL EXCEPTION: main
05-27 05:47:08.824: E/AndroidRuntime(409): java.lang.NullPointerException
05-27 05:47:08.824: E/AndroidRuntime(409):  at library.UserFunctions.registerUser(UserFunctions.java:68)
05-27 05:47:08.824: E/AndroidRuntime(409):  at com.example.androidhive.RegisterActivity$1.onClick(RegisterActivity.java:55)
05-27 05:47:08.824: E/AndroidRuntime(409):  at android.view.View.performClick(View.java:2485)
05-27 05:47:08.824: E/AndroidRuntime(409):  at android.view.View$PerformClick.run(View.java:9080)
05-27 05:47:08.824: E/AndroidRuntime(409):  at android.os.Handler.handleCallback(Handler.java:587)
05-27 05:47:08.824: E/AndroidRuntime(409):  at android.os.Handler.dispatchMessage(Handler.java:92)
05-27 05:47:08.824: E/AndroidRuntime(409):  at android.os.Looper.loop(Looper.java:130)
05-27 05:47:08.824: E/AndroidRuntime(409):  at android.app.ActivityThread.main(ActivityThread.java:3683)
05-27 05:47:08.824: E/AndroidRuntime(409):  at java.lang.reflect.Method.invokeNative(Native Method)
05-27 05:47:08.824: E/AndroidRuntime(409):  at java.lang.reflect.Method.invoke(Method.java:507)
05-27 05:47:08.824: E/AndroidRuntime(409):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
05-27 05:47:08.824: E/AndroidRuntime(409):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
05-27 05:47:08.824: E/AndroidRuntime(409):  at dalvik.system.NativeStart.main(Native Method)

没有名称值对的Logcat 200 ok：

05-27 05:51:39.863: D/dalvikvm(444): GC_EXTERNAL_ALLOC freed 70K, 49% free 2778K/5379K, external 2032K/2137K, paused 40ms
05-27 05:51:46.415: W/KeyCharacterMap(444): No keyboard for id 0
05-27 05:51:46.415: W/KeyCharacterMap(444): Using default keymap: /system/usr/keychars/qwerty.kcm.bin
05-27 05:52:06.862: V/register user(444): no  value@pairs.com url
05-27 05:52:06.862: V/url placed in json object(444): http://www.leobee.com/android/push/login/index.php?
05-27 05:52:06.883: V/name value pairs(444): [tag=register, name=no, email=value@pairs.com, password=url]
05-27 05:52:07.893: V/Http Response(444): HTTP/1.1 200 OK
05-27 05:52:07.902: E/JSON(444): Access Deniedn
05-27 05:52:07.912: E/JSON Parser(444): Error parsing data org.json.JSONException: Value Access of type java.lang.String cannot be converted to JSONObject
05-27 05:52:07.912: D/AndroidRuntime(444): Shutting down VM
05-27 05:52:07.912: W/dalvikvm(444): threadid=1: thread exiting with uncaught exception (group=0x40015560)
05-27 05:52:07.923: E/AndroidRuntime(444): FATAL EXCEPTION: main
05-27 05:52:07.923: E/AndroidRuntime(444): java.lang.NullPointerException
05-27 05:52:07.923: E/AndroidRuntime(444):  at library.UserFunctions.registerUser(UserFunctions.java:68)
05-27 05:52:07.923: E/AndroidRuntime(444):  at com.example.androidhive.RegisterActivity$1.onClick(RegisterActivity.java:55)
05-27 05:52:07.923: E/AndroidRuntime(444):  at android.view.View.performClick(View.java:2485)
05-27 05:52:07.923: E/AndroidRuntime(444):  at android.view.View$PerformClick.run(View.java:9080)
05-27 05:52:07.923: E/AndroidRuntime(444):  at android.os.Handler.handleCallback(Handler.java:587)
05-27 05:52:07.923: E/AndroidRuntime(444):  at android.os.Handler.dispatchMessage(Handler.java:92)
05-27 05:52:07.923: E/AndroidRuntime(444):  at android.os.Looper.loop(Looper.java:130)
05-27 05:52:07.923: E/AndroidRuntime(444):  at android.app.ActivityThread.main(ActivityThread.java:3683)
05-27 05:52:07.923: E/AndroidRuntime(444):  at java.lang.reflect.Method.invokeNative(Native Method)
05-27 05:52:07.923: E/AndroidRuntime(444):  at java.lang.reflect.Method.invoke(Method.java:507)
05-27 05:52:07.923: E/AndroidRuntime(444):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
05-27 05:52:07.923: E/AndroidRuntime(444):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
05-27 05:52:07.923: E/AndroidRuntime(444):  at dalvik.system.NativeStart.main(Native Method)

Answer 1

看起来您收到访问被拒绝错误，导致您的用户在注册用户时崩溃。

尝试下面的内容：

删除注册网址末尾的询问标记。
你应该声明那些私有的最终静态，因为网址不会改变
使用来自apache common io的IOUtils.toString将实体转换为字符串，你的实现不是那么好，你使用的缓冲区太小了。更喜欢将Apache项目用于此类任务。
打印从服务器收到的内容，服务器响应的内容可能不是json。

HttpPost android：500服务器错误，名称值对，200 ok，url中没有名称值对

1 个答案: