我正在关注this教程，并收到此错误：
Caused by: java.lang.NoSuchMethodError: No virtual method execute(Lorg/apache/http/client/methods/HttpUriRequest;)Lorg/apache/http/client/methods/CloseableHttpResponse; in class Lorg/apache/http/impl/client/DefaultHttpClient; or its super classes (declaration of 'org.apache.http.impl.client.DefaultHttpClient' appears in /system/framework/ext.jar)
at info.androidhive.materialtabs.adpater.JSONParser.makeHttpRequest(JSONParser.java:52)
at info.androidhive.materialtabs.UserFunctions.loginUser(UserFunctions.java:37)
at info.androidhive.materialtabs.activity.MainActivity$Login.doInBackground(MainActivity.java:551)
at info.androidhive.materialtabs.activity.MainActivity$Login.doInBackground(MainActivity.java:519)
这是我正在使用的JSONParser类：
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;
}
}
答案 0 :(得分：10)
DefaultHttpClient在api级别22中已弃用，并在api级别23中删除。
甚至从Android文档中删除了文档，这里是文档之前的链接，您可以看到它重定向的位置： http://developer.android.com/reference/org/apache/http/impl/client/DefaultHttpClient.html
引用以防重新直接更改：
Android 6.0版本删除了对Apache HTTP客户端的支持。如果 您的应用正在使用此客户端并定位到Android 2.3（API级别9）或 更高，请改用HttpURLConnection类。这个API更多 高效，因为它通过透明减少网络使用 压缩和响应缓存，并最大限度地降低功耗。
我创建了您正在使用的JSONParser类的更新版本，现在它是：
import android.util.Log;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.util.HashMap;
public class JSONParser {
String charset = "UTF-8";
HttpURLConnection conn;
DataOutputStream wr;
StringBuilder result;
URL urlObj;
JSONObject jObj = null;
StringBuilder sbParams;
String paramsString;
public JSONObject makeHttpRequest(String url, String method,
HashMap<String, String> params) {
sbParams = new StringBuilder();
int i = 0;
for (String key : params.keySet()) {
try {
if (i != 0){
sbParams.append("&");
}
sbParams.append(key).append("=")
.append(URLEncoder.encode(params.get(key), charset));
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
i++;
}
if (method.equals("POST")) {
// request method is POST
try {
urlObj = new URL(url);
conn = (HttpURLConnection) urlObj.openConnection();
conn.setDoOutput(true);
conn.setRequestMethod("POST");
conn.setRequestProperty("Accept-Charset", charset);
conn.setReadTimeout(10000);
conn.setConnectTimeout(15000);
conn.connect();
paramsString = sbParams.toString();
wr = new DataOutputStream(conn.getOutputStream());
wr.writeBytes(paramsString);
wr.flush();
wr.close();
} catch (IOException e) {
e.printStackTrace();
}
}
else if(method.equals("GET")){
// request method is GET
if (sbParams.length() != 0) {
url += "?" + sbParams.toString();
}
try {
urlObj = new URL(url);
conn = (HttpURLConnection) urlObj.openConnection();
conn.setDoOutput(false);
conn.setRequestMethod("GET");
conn.setRequestProperty("Accept-Charset", charset);
conn.setConnectTimeout(15000);
conn.connect();
} catch (IOException e) {
e.printStackTrace();
}
}
try {
//Receive the response from the server
InputStream in = new BufferedInputStream(conn.getInputStream());
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
result = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
result.append(line);
}
Log.d("JSON Parser", "result: " + result.toString());
} catch (IOException e) {
e.printStackTrace();
}
conn.disconnect();
// try parse the string to a JSON object
try {
jObj = new JSONObject(result.toString());
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON Object
return jObj;
}
}
Post的AsyncTask示例：
class PostAsync extends AsyncTask<String, String, JSONObject> {
JSONParser jsonParser = new JSONParser();
private ProgressDialog pDialog;
private static final String LOGIN_URL = "http://www.example.com/testPost.php";
private static final String TAG_SUCCESS = "success";
private static final String TAG_MESSAGE = "message";
@Override
protected void onPreExecute() {
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Attempting login...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
@Override
protected JSONObject doInBackground(String... args) {
try {
HashMap<String, String> params = new HashMap<>();
params.put("name", args[0]);
params.put("password", args[1]);
Log.d("request", "starting");
JSONObject json = jsonParser.makeHttpRequest(
LOGIN_URL, "POST", params);
if (json != null) {
Log.d("JSON result", json.toString());
return json;
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
protected void onPostExecute(JSONObject json) {
int success = 0;
String message = "";
if (pDialog != null && pDialog.isShowing()) {
pDialog.dismiss();
}
if (json != null) {
Toast.makeText(MainActivity.this, json.toString(),
Toast.LENGTH_LONG).show();
try {
success = json.getInt(TAG_SUCCESS);
message = json.getString(TAG_MESSAGE);
} catch (JSONException e) {
e.printStackTrace();
}
}
if (success == 1) {
Log.d("Success!", message);
}else{
Log.d("Failure", message);
}
}
}
获取的示例AsyncTask：
class GetAsync extends AsyncTask<String, String, JSONObject> {
JSONParser jsonParser = new JSONParser();
private ProgressDialog pDialog;
private static final String LOGIN_URL = "http://www.example.com/testGet.php";
private static final String TAG_SUCCESS = "success";
private static final String TAG_MESSAGE = "message";
@Override
protected void onPreExecute() {
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Attempting login...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
@Override
protected JSONObject doInBackground(String... args) {
try {
HashMap<String, String> params = new HashMap<>();
params.put("name", args[0]);
params.put("password", args[1]);
Log.d("request", "starting");
JSONObject json = jsonParser.makeHttpRequest(
LOGIN_URL, "GET", params);
if (json != null) {
Log.d("JSON result", json.toString());
return json;
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
protected void onPostExecute(JSONObject json) {
int success = 0;
String message = "";
if (pDialog != null && pDialog.isShowing()) {
pDialog.dismiss();
}
if (json != null) {
Toast.makeText(MainActivity.this, json.toString(),
Toast.LENGTH_LONG).show();
try {
success = json.getInt(TAG_SUCCESS);
message = json.getString(TAG_MESSAGE);
} catch (JSONException e) {
e.printStackTrace();
}
}
if (success == 1) {
Log.d("Success!", message);
}else{
Log.d("Failure", message);
}
}
}
有关详细信息，请参阅我的博文，其中包含此代码：http://danielnugent.blogspot.com/2015/06/updated-jsonparser-with.html