在服务器与客户端之间通信，json数据是一种常用格式，本文主要在服务器端构建数据，在客户端接收显示，并且在listview上显示出来
服务器端的构建
简单的javabean与返回结果函数与插入函数略过
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
response.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter();
List<MyShop> shops = JsonService.getListShop();
StringBuffer sb = new StringBuffer();
sb.append('[');
for (MyShop shop : shops) {
sb.append('{').append("\"name\":").append("\""+shop.getName()+"\"").append(",");
sb.append("\"detail\":").append("\""+shop.getDetail()+"\"").append(",");
sb.append("\"distance\":").append("\""+shop.getDistance()+"\"").append(",");
sb.append("\"address\":").append("\""+shop.getAddress()+"\"").append(",");
sb.append("\"popularity\":").append(shop.getPopularity());
sb.append('}').append(",");
}
sb.deleteCharAt(sb.length() - 1);
sb.append(']');
out.write(new String(sb));
out.flush();
out.close();
}
在浏览器中直接输入访问http://localhost:8080/AppServer/JsonServlet
可得
可以在服务器端直接查看json数据
客户端接收与解析json数据
public class JsonParse {
/**
* 解析Json数据
*
* @param urlPath
* @return mlists
* @throws Exception
*/
public static List<MyShop> getListShop(String urlPath) throws Exception {
List<MyShop> mlists = new ArrayList<MyShop>();
byte[] data = readParse(urlPath);
JSONArray array = new JSONArray(new String(data));
for (int i = 0; i < array.length(); i++) {
JSONObject item = array.getJSONObject(i);
String name = item.getString("name");
String detail = item.getString("detail");
String distance = item.getString("distance");
String popularity = item.getString("popularity");
String address = item.getString("address");
mlists.add(new MyShop(name, detail, distance,address,popularity));
}
return mlists;
}
/**
* 从指定的url中获取字节数组
*
* @param urlPath
* @return 字节数组
* @throws Exception
*/
public static byte[] readParse(String urlPath) throws Exception {
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
byte[] data = new byte[1024];
int len = 0;
URL url = new URL(urlPath);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
InputStream inStream = conn.getInputStream();
while ((len = inStream.read(data)) != -1) {
outStream.write(data, 0, len);
}
inStream.close();
return outStream.toByteArray();
}
}
在activity中开启子线程来接收服务器数据
new Thread(new Runnable() {
private String tag;
@Override
public void run() {
// TODO Auto-generated method stub
//获得新闻集合
List<MyShop> shopList = null;
try {
shopList = JsonParse.getListShop("http://192.168.247.1:8080/AppServer/JsonServlet");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Log.i(tag, "在RUN中LIST长度为"+shopList.size());
Message msg=new Message();
if(shopList!=null)
{
msg.what=SUCCESS;
msg.obj=shopList;
}else
{
msg.what=FAILED;
}
handler.sendMessage(msg);
Log.i(tag, "***********T长度为"+shopList.size());
}
}).start();
消息处理器
//消息处理器
private Handler handler=new Handler(){
/**
* 接收消息
*/
@Override
public void handleMessage(Message msg) {
// TODO Auto-generated method stub
String tag = null;
switch (msg.what) {
case SUCCESS: //访问成功，有数据
//绑定数据
Log.i(tag,"%%%%%%%%%%到达了消息处理器");
myshoplist=(List<MyShop>) msg.obj;
Log.i(tag, "handleMessage中数据newInfoList长度为"+myshoplist.size());
NearAdapter adapter=new NearAdapter();
Log.i(tag, "有没有到达ADAPTER"+adapter.getCount());
showList.setAdapter(adapter);
break;
case FAILED: //访问失败
Toast.makeText(ChooseMer.this, "当前网络崩溃了", 0).show();
break;
default:
break;
}
}
};
配置适配器
public class NearAdapter extends BaseAdapter {
@Override
public int getCount() {
// TODO Auto-generated method stub
return myshoplist.size();
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return null;
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return 0;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if (convertView == null) {
LayoutInflater inflater = LayoutInflater
.from(ChooseMer.this);
convertView = inflater.inflate(R.layout.nearby_list_item, null);
init(convertView,position);
}
return convertView;
}
public void init(View convertView,int position) {
hold.name = (TextView) convertView
.findViewById(R.id.nearby_item_name);
MyShop shop=myshoplist.get(position);
hold.name.setText(shop.getName());
hold.local = (TextView) convertView
.findViewById(R.id.nearby_item_local);
hold.local.setText(shop.getDetail());
hold.dis1 = (TextView) convertView
.findViewById(R.id.nearby_item_dis1);
hold.dis1.setText(shop.getDistance());
hold.dis2 = (TextView) convertView
.findViewById(R.id.nearby_item_dis2);
hold.dis2.setText(shop.getAddress());
hold.dis3 = (TextView) convertView
.findViewById(R.id.nearby_item_dis3);
hold.dis3.setText(shop.getPopularity());
}
}
配置完成，效果如下
安卓客户端向服务器发送json数据实现
方法一
public void sendJsonToServer() {
HttpClient httpClient = new DefaultHttpClient();
try {
HttpPost httpPost = new HttpPost(constant.url);
HttpParams httpParams = new BasicHttpParams();
List<NameValuePair> nameValuePair = new ArrayList<NameValuePair>();
Gson gson = new Gson();
String str = gson.toJson(initData());
nameValuePair.add(new BasicNameValuePair("jsonString", URLEncoder
.encode(str, "utf-8")));
httpPost.setEntity(new UrlEncodedFormEntity(nameValuePair));
httpPost.setParams(httpParams);
Toast.makeText(Main.this, "发送的数据：\n" + str.toString(),
Toast.LENGTH_SHORT).show();
httpClient.execute(httpPost);
HttpResponse response = httpClient.execute(httpPost);
StatusLine statusLine = response.getStatusLine();
if (statusLine != null && statusLine.getStatusCode() == 200) {
HttpEntity entity = response.getEntity();
if (entity != null) {
Toast.makeText(
Main.this,
"服务器处理返回结果：" + readInputStream(entity.getContent()),
Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(Main.this, "没有返回相关数据", Toast.LENGTH_SHORT)
.show();
}
} else {
Toast.makeText(Main.this, "发送失败，可能服务器忙，请稍后再试",
Toast.LENGTH_SHORT).show();
}
} catch (Exception e) {
throw new RuntimeException(e);
}
}
private static String readInputStream(InputStream is) throws IOException {
if (is == null)
return null;
ByteArrayOutputStream bout = new ByteArrayOutputStream();
int len = 0;
byte[] buf = new byte[1024];
while ((len = is.read(buf)) != -1) {
bout.write(buf, 0, len);
}
is.close();
return URLDecoder.decode(new String(bout.toByteArray()), "utf-8");
}
/*
* 填充数据源
*/
public List<Product> initData() {
List<Product> persons = new ArrayList<Product>();
for (int i = 0; i < 5; i++) {
Product p = new Product();
p.setLocation("所在位置");
p.setName("名称" + i);
persons.add(p);
}
return persons;
}
参考链接
方法二
public void SendData()
{
if(IntentState!=1)
{
return;
}
if(nowId>=getTop())
{
return;
}
CarBean myCar=queryItem(nowId);
/*StringBuffer sb = new StringBuffer();
sb.append('[');
sb.append('{').append("\"rpm\":").append("\""+myCar.getRpm()+"\"").append(",");
sb.append("\"speed\":").append("\""+myCar.getSpeed()+"\"").append(",");
sb.append("\"airSpeed\":").append("\""+myCar.getAirSpeed()+"\"").append(",");
sb.append("\"throttle\":").append("\""+myCar.getThrottle()+"\"").append(",");
sb.append("\"oilLevel\":").append("\""+myCar.getOilLevel()+"\"");
sb.append('}');
sb.append(']');
Log.i("test", sb.toString());*/
JSONObject jsonObject=new JSONObject();
try {
jsonObject.put("0C", myCar.getRpm());
jsonObject.put("0D",myCar.getSpeed());
jsonObject.put("10",myCar.getAirSpeed());
jsonObject.put("11",myCar.getThrottle());
jsonObject.put("2F",myCar.getOilLevel());
strJSON = String.valueOf(jsonObject);
System.out.println(strJSON);
Log.i("test", "result===="+strJSON);
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
new Thread(new Runnable() {
@Override
public void run() {
// TODO Auto-generated method stub
System.out.println("strJSON ready to launch!" + strJSON);
HttpURLConnection conn = null;
String content = "";
try {
Log.i("test", "test1");
URL url = new URL(
"http://192.168.1.130:8080/Test/transAction");
conn = (HttpURLConnection) url.openConnection();
Log.i("test", "test2");
conn.setDoInput(true);
conn.setDoOutput(true);
conn.setConnectTimeout(1000 * 30);
conn.setReadTimeout(1000 * 30);
conn.setRequestMethod("GET");
conn.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
OutputStream output = conn.getOutputStream();
output.write(strJSON.getBytes());
output.flush();
output.close();
// 关闭流对象。此时，不能再向对象输出流写入任何数据，先前写入的数据存在于内存缓冲区中,
// 在调用下边的getInputStream()函数时才把准备好的http请求正式发送到服务器
// objOutputStrm.close();
InputStream in = conn.getInputStream();
Log.i("test", "test3");
int responseCode = conn.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_OK) {
Log.i("test", "test4");
System.out.println("responseCode=" + HttpURLConnection.HTTP_OK);
// InputStreamReader reader = new
// InputStreamReader(in,charSet);
delete(nowId);
nowId++;
Message msg=new Message();
msg.what=3;
handler.sendMessage(msg);
BufferedReader reader = new BufferedReader(new InputStreamReader(in, "UTF-8"));
String line = null;
while ((line = reader.readLine()) != null) {
content += line;
}
System.out.println("result:" + content);
}else
{
Log.i("test", "test5");
}
in.close();
} catch (Exception e) {
e.printStackTrace();
Log.i("test", "test6");
} finally {
conn.disconnect();
conn = null;
Log.i("test", "test7");
}
strJSON = "null";
}
}).start();
}