本文主要包括三方面内容
Httpurlconnection中doGet与doPost方法实现提交数据到服务器
HttpClient中doGet与doPost方法实现提交数据到服务器
android-async-http开源库方法实现提交数据到服务器
首先是服务器端的实现
public class LoginServlet extends HttpServlet {/*** The doGet method of the servlet. <br>** This method is called when a form has its tag value method equals to get.* * @param request the request send by the client to the server* @param response the response send by the server to the client* @throws ServletException if an error occurred* @throws IOException if an error occurred*/public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {String username = request.getParameter("username"); // 采用的编码是: iso-8859-1String password = request.getParameter("password");// 采用iso8859-1的编码对姓名进行逆转, 转换成字节数组, 再使用utf-8编码对数据进行转换, 字符串username = new String(username.getBytes("iso8859-1"), "utf-8");password = new String(password.getBytes("iso8859-1"), "utf-8");System.out.println("姓名: " + username);System.out.println("密码: " + password);if("lisi".equals(username) && "123".equals(password)) {/** getBytes 默认情况下, 使用的iso8859-1的编码, 但如果发现码表中没有当前字符, * 会使用当前系统下的默认编码: GBK*/ response.getOutputStream().write("登录成功".getBytes("utf-8"));} else {response.getOutputStream().write("登录失败".getBytes("utf-8"));}}/*** The doPost method of the servlet. <br>** This method is called when a form has its tag value method equals to post.* * @param request the request send by the client to the server* @param response the response send by the server to the client* @throws ServletException if an error occurred* @throws IOException if an error occurred*/public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {System.out.println("doPost");doGet(request, response);}}
Httpurlconnection实现提交数据到服务器
public class NetUtils {private static final String TAG = "NetUtils";/*** 使用post的方式登录* @param userName* @param password* @return*/public static String loginOfPost(String userName, String password) {HttpURLConnection conn = null;try {URL url = new URL("http://10.0.2.2:8080/ServerItheima28/servlet/LoginServlet");conn = (HttpURLConnection) url.openConnection();conn.setRequestMethod("POST");conn.setConnectTimeout(10000); // 连接的超时时间conn.setReadTimeout(5000); // 读数据的超时时间conn.setDoOutput(true); // 必须设置此方法, 允许输出
// conn.setRequestProperty("Content-Length", 234); // 设置请求头消息, 可以设置多个// post请求的参数String data = "username=" + userName + "&password=" + password;// 获得一个输出流, 用于向服务器写数据, 默认情况下, 系统不允许向服务器输出内容OutputStream out = conn.getOutputStream(); out.write(data.getBytes());out.flush();out.close();int responseCode = conn.getResponseCode();if(responseCode == 200) {InputStream is = conn.getInputStream();String state = getStringFromInputStream(is);return state;} else {Log.i(TAG, "访问失败: " + responseCode);}} catch (Exception e) {e.printStackTrace();} finally {if(conn != null) {conn.disconnect();}}return null;}/*** 使用get的方式登录* @param userName* @param password* @return 登录的状态*/public static String loginOfGet(String userName, String password) {HttpURLConnection conn = null;try {String data = "username=" + URLEncoder.encode(userName) + "&password=" + URLEncoder.encode(password);URL url = new URL("http://10.0.2.2:8080/ServerItheima28/servlet/LoginServlet?" + data);conn = (HttpURLConnection) url.openConnection();conn.setRequestMethod("GET"); // get或者post必须得全大写conn.setConnectTimeout(10000); // 连接的超时时间conn.setReadTimeout(5000); // 读数据的超时时间int responseCode = conn.getResponseCode();if(responseCode == 200) {InputStream is = conn.getInputStream();String state = getStringFromInputStream(is);return state;} else {Log.i(TAG, "访问失败: " + responseCode);}} catch (Exception e) {e.printStackTrace();} finally {if(conn != null) {conn.disconnect(); // 关闭连接}}return null;}/*** 根据流返回一个字符串信息* @param is* @return* @throws IOException */private static String getStringFromInputStream(InputStream is) throws IOException {ByteArrayOutputStream baos = new ByteArrayOutputStream();byte[] buffer = new byte[1024];int len = -1;while((len = is.read(buffer)) != -1) {baos.write(buffer, 0, len);}is.close();String html = baos.toString(); // 把流中的数据转换成字符串, 采用的编码是: utf-8// String html = new String(baos.toByteArray(), "GBK");baos.close();return html;}
}
HttpClient实现提交数据到服务器
public class NetUtils2 {private static final String TAG = "NetUtils";/*** 使用post的方式登录* @param userName* @param password* @return*/public static String loginOfPost(String userName, String password) {HttpClient client = null;try {// 定义一个客户端client = new DefaultHttpClient();// 定义post方法HttpPost post = new HttpPost("http://10.0.2.2:8080/ServerItheima28/servlet/LoginServlet");// 定义post请求的参数List<NameValuePair> parameters = new ArrayList<NameValuePair>();parameters.add(new BasicNameValuePair("username", userName));parameters.add(new BasicNameValuePair("password", password));// 把post请求的参数包装了一层.// 不写编码名称服务器收数据时乱码. 需要指定字符集为utf-8UrlEncodedFormEntity entity = new UrlEncodedFormEntity(parameters, "utf-8");// 设置参数.post.setEntity(entity);// 设置请求头消息
// post.addHeader("Content-Length", "20");// 使用客户端执行post方法HttpResponse response = client.execute(post); // 开始执行post请求, 会返回给我们一个HttpResponse对象// 使用响应对象, 获得状态码, 处理内容int statusCode = response.getStatusLine().getStatusCode(); // 获得状态码if(statusCode == 200) {// 使用响应对象获得实体, 获得输入流InputStream is = response.getEntity().getContent();String text = getStringFromInputStream(is);return text;} else {Log.i(TAG, "请求失败: " + statusCode);}} catch (Exception e) {e.printStackTrace();} finally {if(client != null) {client.getConnectionManager().shutdown(); // 关闭连接和释放资源}}return null;}/*** 使用get的方式登录* @param userName* @param password* @return 登录的状态*/public static String loginOfGet(String userName, String password) {HttpClient client = null;try {// 定义一个客户端client = new DefaultHttpClient();// 定义一个get请求方法String data = "username=" + userName + "&password=" + password;HttpGet get = new HttpGet("http://10.0.2.2:8080/ServerItheima28/servlet/LoginServlet?" + data);// response 服务器相应对象, 其中包含了状态信息和服务器返回的数据HttpResponse response = client.execute(get); // 开始执行get方法, 请求网络// 获得响应码int statusCode = response.getStatusLine().getStatusCode();if(statusCode == 200) {InputStream is = response.getEntity().getContent();String text = getStringFromInputStream(is);return text;} else {Log.i(TAG, "请求失败: " + statusCode);}} catch (Exception e) {e.printStackTrace();} finally {if(client != null) {client.getConnectionManager().shutdown(); // 关闭连接, 和释放资源}}return null;}/*** 根据流返回一个字符串信息* @param is* @return* @throws IOException */private static String getStringFromInputStream(InputStream is) throws IOException {ByteArrayOutputStream baos = new ByteArrayOutputStream();byte[] buffer = new byte[1024];int len = -1;while((len = is.read(buffer)) != -1) {baos.write(buffer, 0, len);}is.close();String html = baos.toString(); // 把流中的数据转换成字符串, 采用的编码是: utf-8// String html = new String(baos.toByteArray(), "GBK");baos.close();return html;}
}
在onCreate方法中的调用
public class MainActivity extends Activity {private EditText etUserName;private EditText etPassword;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);etUserName = (EditText) findViewById(R.id.et_username);etPassword = (EditText) findViewById(R.id.et_password);}public void doGet(View v) {final String userName = etUserName.getText().toString();final String password = etPassword.getText().toString();new Thread(new Runnable() {@Overridepublic void run() {// 使用get方式抓去数据final String state = NetUtils.loginOfGet(userName, password);// 执行任务在主线程中runOnUiThread(new Runnable() {@Overridepublic void run() {// 就是在主线程中操作Toast.makeText(MainActivity.this, state, 0).show();}});}}).start();}public void doPost(View v) {final String userName = etUserName.getText().toString();final String password = etPassword.getText().toString();new Thread(new Runnable() {@Overridepublic void run() {final String state = NetUtils.loginOfPost(userName, password);// 执行任务在主线程中runOnUiThread(new Runnable() {@Overridepublic void run() {// 就是在主线程中操作Toast.makeText(MainActivity.this, state, 0).show();}});}}).start();}
}
使用runOnUiThread方法,可以在子线程中实现对主线程的操作
使用android-async-http开源库方法实现提交数据到服务器 ,使用方法也是将src文件夹中的内容复制到程序中即可
public class MainActivity2 extends Activity {protected static final String TAG = "MainActivity2";private EditText etUserName;private EditText etPassword;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);etUserName = (EditText) findViewById(R.id.et_username);etPassword = (EditText) findViewById(R.id.et_password);}public void doGet(View v) {final String userName = etUserName.getText().toString();final String password = etPassword.getText().toString();AsyncHttpClient client = new AsyncHttpClient();String data = "username=" + URLEncoder.encode(userName) + "&password=" + URLEncoder.encode(password);client.get("http://10.0.2.2:8080/ServerItheima28/servlet/LoginServlet?" + data, new MyResponseHandler());}public void doPost(View v) {final String userName = etUserName.getText().toString();final String password = etPassword.getText().toString();AsyncHttpClient client = new AsyncHttpClient();RequestParams params = new RequestParams();params.put("username", userName);params.put("password", password);client.post("http://10.0.2.2:8080/ServerItheima28/servlet/LoginServlet", params, new MyResponseHandler());}class MyResponseHandler extends AsyncHttpResponseHandler {@Overridepublic void onSuccess(int statusCode, Header[] headers,byte[] responseBody) {
// Log.i(TAG, "statusCode: " + statusCode);Toast.makeText(MainActivity2.this, "成功: statusCode: " + statusCode + ", body: " + new String(responseBody), 0).show();}@Overridepublic void onFailure(int statusCode, Header[] headers,byte[] responseBody, Throwable error) {Toast.makeText(MainActivity2.this, "失败: statusCode: " + statusCode, 0).show();}}
}