我就以我做的一个无线点菜系统为例，服务器端放在pc上，使用tomcat服务器，用servlet写的服务器端，客户端用android。
1.
首先看客户端在客户端我们要发送请求我要得到什么，那么服务器端就看你出的条件了，所谓条件就是参数，你传参数是不传参数，如果不传参数很好办，传参数也好办，哈哈
现在我们看不传参数怎么办，我们把请求的方法全部写在HttpUitl这个类里边
代码如下：
packagecom.Mobile.util;
importjava.io.BufferedReader;
importjava.io.IOException;
importjava.io.InputStreamReader;
importorg.apache.http.HttpEntity;
importorg.apache.http.HttpResponse;
importorg.apache.http.client.ClientProtocolException;
importorg.apache.http.client.HttpClient;
importorg.apache.http.client.methods.HttpGet;
importorg.apache.http.client.methods.HttpPost;
importorg.apache.http.impl.client.DefaultHttpClient;
importorg.apache.http.params.HttpConnectionParams;
importorg.apache.http.params.HttpParams;
importorg.apache.http.util.EntityUtils;
publicclass HttpUtil {
// 基础URL
Public static final StringBASE_URL="http://10.10.120.147:8080/WirelessOrder_Service/";
// 获得Get请求对象request
public static HttpGet getHttpGet(String url){
HttpGet request = new HttpGet(url);
return request;
}
// 获得Post请求对象request
public static HttpPost getHttpPost(String url){
HttpPost request = new HttpPost(url);
return request;
}
// 根据请求获得响应对象response
public static HttpResponsegetHttpResponse(HttpGet request) throws ClientProtocolException, IOException{
HttpResponse response = newDefaultHttpClient().execute(request);
return response;
}
// 根据请求获得响应对象response
public static HttpResponse getHttpResponse(HttpPostrequest) throws ClientProtocolException, IOException{
HttpResponse response = newDefaultHttpClient().execute(request);
return response;
}
// 发送Post请求，获得响应查询结果
public static String queryStringForPost(Stringurl){
// 根据url获得HttpPost对象
HttpPost request =HttpUtil.getHttpPost(url);
String result = null;
try {
// 获得响应对象
HttpResponse response =HttpUtil.getHttpResponse(request);
// 判断是否请求成功
if(response.getStatusLine().getStatusCode()==200){
// 获得响应
result =EntityUtils.toString(response.getEntity());
return result;
}
} catch (ClientProtocolException e) {
e.printStackTrace();
result = "网络异常!";
return result;
} catch (IOException e) {
e.printStackTrace();
result = "网络异常!";
return result;
}
return null;
}
// 获得响应查询结果
public static StringqueryStringForPost(HttpPost request){
String result = null;
try {
// 获得响应对象
HttpResponse response =HttpUtil.getHttpResponse(request);
// 判断是否请求成功
if(response.getStatusLine().getStatusCode()==200){
// 获得响应
result =EntityUtils.toString(response.getEntity());
return result;
}
} catch (ClientProtocolException e) {
e.printStackTrace();
result = "网络异常！";
return result;
} catch (IOException e) {
e.printStackTrace();
result = "网络异常！";
return result;
}
return null;
}
// 发送Get请求，获得响应查询结果
public static
String queryStringForGet(String url){
// 获得HttpGet对象
HttpGet request =HttpUtil.getHttpGet(url);
String result = null;
try {
// 获得响应对象
HttpResponse response =HttpUtil.getHttpResponse(request);
// 判断是否请求成功
if(response.getStatusLine().getStatusCode()==200){
// 获得响应
result =EntityUtils.toString(response.getEntity());
return result;
}
} catch (ClientProtocolException e) {
e.printStackTrace();
result = "网络异常！";
return result;
} catch (IOException e) {
e.printStackTrace();
result = "网络异常！";
return result;
}
return null;
}
//这个方法是用jSON请求获得JSON
public static String getContent(String url)
{
StringBuilder sb=new StringBuilder();
HttpClient client=newDefaultHttpClient();
HttpParamshttpparams=client.getParams();
HttpConnectionParams.setConnectionTimeout(httpparams,3000);
HttpConnectionParams.setSoTimeout(httpparams,5000);
try {
HttpResponseresponse=client.execute(new HttpGet(url));
HttpEntityentity=response.getEntity();
if(entity!=null)
{
BufferedReaderreader=new BufferedReader(new InputStreamReader(entity.getContent(),"utf8"),8192);
String line=null;
while((line=reader.readLine())!=null)
{
sb.append(line+"\n");
}
reader.close();
}
} catch (ClientProtocolException e) {
// TODO Auto-generated catchblock
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catchblock
e.printStackTrace();
}
return sb.toString();
}
}
下面的代码是客户端请求，插入用户信息
ArrayList<NameValuePair>list=new ArrayList<NameValuePair>();
list.add(new BasicNameValuePair("username",us));
list.add(new BasicNameValuePair("password",pw));
list.add(new BasicNameValuePair("name",na));
list.add(new BasicNameValuePair("weight",we));
list.add(new BasicNameValuePair("sex",se));
UrlEncodedFormEntity entity1=null;
try {
entity1=
new UrlEncodedFormEntity(list,HTTP.UTF_8);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
String url=HttpUtil.BASE_URL+"/InsertServlet";
HttpPostrequest = HttpUtil.getHttpPost(url);
下面是用JSON获得订单的例子
String url=HttpUtil.BASE_URL+"/SelectOrderListServlet?"+"orderid="+orde;
String body=HttpUtil.getContent(url);//这个方法在HttpUtil类里边
try {
JSONArray array=new JSONArray(body);
for(int i=0;i<array.length();i++)
{
JSONObject obj=array.getJSONObject(i);
HashMap m=new HashMap<String,Object>();
m.put("name", obj.getString("name"));
m.put("price", obj.getString("price"));
m.put("num",obj.getString("num"));
m.put("menuid",obj.getString("menuid"));
orderlist.add(m);
}
} catch (JSONException e) {
//TODO Auto-generatedcatch block
e.printStackTrace();
}