使用JSON和PHP将数据插入MAMP服务器

Question

我目前正在开发一个与MAMP服务器通信的Android应用程序。 我在向其中一个表格添加新记录时遇到问题

JSONParser类

    package com.example.transgoods;

    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.HttpGet;
    import org.apache.http.client.methods.HttpPost;
    import org.apache.http.client.utils.URLEncodedUtils;
    import org.apache.http.impl.client.DefaultHttpClient;
    import org.json.JSONException;
    import org.json.JSONObject; 

    import android.util.Log;

    `enter code here`public class JSONParser {

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

    // constructor
    public JSONParser() {

    }

    // function get json from url
    // by making HTTP POST or GET method
    public JSONObject makeHttpRequest(String url, String method,
            List<NameValuePair> params) {

        // Making HTTP request
        try {

            // check for request method
            if(method == "POST"){
                // request method is POST
                // defaultHttpClient
                DefaultHttpClient httpClient = new DefaultHttpClient();
                HttpPost httpPost = new HttpPost(url);
                httpPost.setEntity(new UrlEncodedFormEntity(params));

                HttpResponse httpResponse = httpClient.execute(httpPost);
                HttpEntity httpEntity = httpResponse.getEntity();
                is = httpEntity.getContent();

            }else if(method == "GET"){
                // request method is GET
                DefaultHttpClient httpClient = new DefaultHttpClient();
                String paramString = URLEncodedUtils.format(params, "utf-8");
                url += "?" + paramString;
                HttpGet httpGet = new HttpGet(url);

                HttpResponse httpResponse = httpClient.execute(httpGet);
                HttpEntity httpEntity = httpResponse.getEntity();
                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();
        } 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;

    }
}

MainActivity类

package com.example.transgoods;


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

import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONException;
import org.json.JSONObject;

import com.kosalgeek.asynctask.AsyncResponse;
import com.kosalgeek.asynctask.PostResponseAsyncTask;

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;



public class MainActivity extends Activity implements OnClickListener {

private ProgressDialog pDialog;

JSONParser jsonParser = new JSONParser();   
Intent startActivity;
EditText txtCarId;
private int success;

// url to create new product
private static String insert_new_car = "http://10.0.2.2/insert_new.php";

// JSON Node names
private static final String TAG_SUCCESS = "success";

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);  


    //edit text
    txtCarId = (EditText) findViewById(R.id.txtCarID);

    //start activity
    startActivity = new Intent(this, StartActivity.class);


    //button
    Button btnNext = (Button) findViewById(R.id.btnCarNext);
    btnNext.setOnClickListener(this);
}

@Override
public void onClick(View v) {
    // TODO Auto-generated method stub
    if(v.getId() == R.id.btnCarNext){
        new InsertNewCar().execute();
        if(success == 1){
            Toast.makeText(getApplicationContext(), "new car saved", Toast.LENGTH_LONG).show();
        }else{
            Toast.makeText(getApplicationContext(), "new car failed to save", Toast.LENGTH_LONG).show();
        }

    }
}


    /**
     * Background Async Task to Create new product
     * */
    class InsertNewCar extends AsyncTask<String, String, String> {

        //get value for EditText
        String carLicenseNo = txtCarId.getText().toString();

        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(MainActivity.this);
            pDialog.setMessage("Creating Product ("+carLicenseNo+")...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        /**
         * Creating product
         * */
        protected String doInBackground(String... args) {

            // Building Parameters
            List<NameValuePair> params = new ArrayList<NameValuePair>();
            params.add(new BasicNameValuePair("carLicenseNo", carLicenseNo));


            // getting JSON Object
            // Note that create product url accepts POST method
            JSONObject json = jsonParser.makeHttpRequest(insert_new_car,
                    "POST", params);


            return null;

        }

        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) {
            // dismiss the dialog once done
            pDialog.dismiss();
        }

    }

}

用于插入数据的PHP脚本

    <?php

//array for json response
$response = array();

//check for required fields
if(isset($_GET[carLicenseNo])){

    $carLicenseNo = $_GET['carLicenseNo']

//include db connect class
    require_once __DIR__ . '/connect.php';

//connecting to db
    $db = new DB_CONNECT();

    //mysql inserting a new row
    $result = mysql_query("INSERT INTO Cars(carLicenseNo) VALUES('', $carLicenseNo)");

    //Check if row inserted or not
    if ($result){

        //success insert into db
        $response["sucess"] =1;
        $response["message"] = "new car saved...";

        //echoing JSON response
        echo json_encode($response);

    } else {
        //failed to insert row
        $response ["success"] = 0;
        $response["message"] = "An error has occurred....";

        echo json_encode($response);

    }


}else {

    //required field is missing
    $response["success"] = 0; 
    $response["message"] = "Required field(s) is missing";

    //echo json response
    echo json_encode($response);
}
?>

当我在我的模拟器中运行应用程序时，我收到此错误

03-22 04:54:54.215: E/JSON Parser(2002): Error parsing data 
org.json.JSONException: End of input at character 0 of 

我猜测解析器有错误，但我似乎无法找到问题所在。有没有人对我为什么一直收到这个错误有任何想法？

此致