HttpURLConnection与HttpClient的Get与Post请求数据流程

HttpURLConnection与HttpClient的Get与Post请求数据流程

在开发一年的时间里，一直用着已经封装好的Volley框架，时间久了却忘记了基本的网络请求方式，问了把基础巩固，随便写写，加深自己对网络请求的认识:

网络请求有两种方式，HttpClient与HttpURLConnection，他们都可以做get和post请求。

下面一一来分析：

HttpClient的Get请求流程，详情见注释：

private void doHttpGet() {

try {
// 1，先对数据进行键值对的封装，键值对BasicNameValuePair
List<BasicNameValuePair> list = new ArrayList<BasicNameValuePair>();
list.add(new BasicNameValuePair("s", "ss"));
list.add(new BasicNameValuePair("info", "from & jerry"));

// 2，对数据进行编码，url的编码
String data = URLEncodedUtils.format(list, "utf-8");
//3.new 一个HttpClient对象
HttpClient client = new DefaultHttpClient();
//4.设置HttpClient对象的参数，即请求参数HttpConnectionParams
HttpConnectionParams.setConnectionTimeout(client.getParams(), 3000);
HttpConnectionParams.setSoTimeout(client.getParams(), 3000);
//5.new一个HttpGet请求，并把数据跟在URL后面
HttpGet get = new HttpGet("http://www.baidu.com/todo?" + data);
//6.new 一个HttpResponse，相应对象，执行请求的返回相应对象
HttpResponse response = client.execute(get);
//7.得到相应数据，response.getEntity()
if (HttpStatus.SC_OK == response.getStatusLine().getStatusCode()) {

String str = EntityUtils.toString(response.getEntity());

}
} catch (Exception e) {
e.printStackTrace();
}
}

HttpClient的Post请求流程，与get请求大同小异，区别是post数据是放在实体对象中，详情见注释：

private void doHttpPost() {
// 数据
List<BasicNameValuePair> list = new ArrayList<BasicNameValuePair>();
list.add(new BasicNameValuePair("s", "ss"));
list.add(new BasicNameValuePair("info", "from & jerry"));

HttpClient client = new DefaultHttpClient();

HttpConnectionParams.setConnectionTimeout(client.getParams(), 3000);
HttpConnectionParams.setSoTimeout(client.getParams(), 3000);

HttpPost post = new HttpPost("http://www.baidu.com");

try {
//设置键值对数据于UrlEncodedFormEntity 对象
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(list);
//设置提交的表单实体对象
post.setEntity(entity);
HttpResponse response = client.execute(post);

String result = EntityUtils.toString(response.getEntity(), "utf-8");

} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

HttpURLConnection的Get请求流程,详情见注释：

private void doUrlGet() {
try {
// 1，先对数据进行键值对的封装，键值对BasicNameValuePair
List<BasicNameValuePair> list = new ArrayList<BasicNameValuePair>();
list.add(new BasicNameValuePair("s", "ss"));
list.add(new BasicNameValuePair("info", "from & jerry"));

// 2，对数据进行编码，url的编码
String data = URLEncodedUtils.format(list, "utf-8");
//3.通过URL对象的openConnection（）得到一个HttpURLConnection 对象
URL url = new URL("http://www.baidu.com/todo?" + data);
HttpURLConnection connection = (HttpURLConnection) url
.openConnection();

//4.设置HttpURLConnection对象的参数，即请求参数
connection.setRequestMethod("GET");// 必须大写
connection.setDoInput(true);
connection.setUseCaches(false);
connection.setConnectTimeout(3000);
connection.setReadTimeout(3000);

//5.得到conn的输入流，即相应返回的数据
InputStream in = connection.getInputStream();
//6.读取数据
//**********此处省略
//7.关闭连接
in.close();
connection.disconnect();// 关闭连接
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}

HttpURLConnection的Post请求流程，与get请求大同小异，区别是post数据是放在conn的输出流中，详情见注释：

private void doUrlPost() {
try {
List<BasicNameValuePair> list = new ArrayList<BasicNameValuePair>();
list.add(new BasicNameValuePair("s", "ss"));
list.add(new BasicNameValuePair("info", "from & jerry"));

URL url = new URL("http://www.baidu.com/todo");
HttpURLConnection connection = (HttpURLConnection) url
.openConnection();
connection.setRequestMethod("POST");// post请求必须写，默认是get请求

connection.setDoInput(true);// 发送数据
connection.setDoOutput(true);// 接收数据

connection.setDefaultUseCaches(false);
connection.setRequestProperty("content-type", "application/x-form");

connection.connect();
String data = URLEncodedUtils.format(list, "utf-8");
OutputStream out = connection.getOutputStream();// 先获得输出流，写数据，在获得输入流
// 先发送，在接收

out.write(data.getBytes());
out.flush();
out.close();

InputStream in = connection.getInputStream();
// 读取数据

in.close();

} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

ok分析完成….