网络操作基础

1.HttpURLConnection:

GET:

private void sendRequestWithHttpURLconnection () {    new Thread(new Runnable() {        @Override        public void run() {            HttpURLConnection connection = null;            BufferedReader reader = null;            try {                URL url = new URL("http://bing.com");                connection = (HttpURLConnection) url.openConnection();                connection.setRequestMethod("GET");                connection.setConnectTimeout(8000);                connection.setReadTimeout(8000);                InputStream in = connection.getInputStream();                reader = new BufferedReader(new InputStreamReader(in));                StringBuilder response = new StringBuilder();                String line;                while ((line = reader.readLine()) != null) {                    response.append(line);                }                showResponse(response.toString());            } catch (Exception e){                e.printStackTrace();            } finally {                if (reader != null) {                    try {                        reader.close();                    } catch (IOException e) {                        e.printStackTrace();                    }                }                if (connection != null) {                    connection.disconnect();                }            }        }    }).start();}private void showResponse(final String response) {    runOnUiThread(new Runnable() {        @Override        public void run() {            responseTest.setText(response);        }    });}

POST:

connection.setRequestMethod("POST");

DataOutputStream out = new DataOutputStream(connection.getOutputStream());

out.writeBytes("username=admin&password=233");

2.OKHttp

GET:

OkHttpClient client = new OkHttpClient();

Request request = new Request.Builder().url("http://g.cn").build();

Response respone = client.newCall(request).execute();

String responseData = response.body().string

POST:

Request requestBody = new FormBody.Builder().add("username","admin").add("password","666").build();

Request request = newe Request.Builder().url("http://g.cn").post(requestBody).build();

compile 'com.squareup.okhttp3:okhttp:3.6.0'

private void sendRequestWithOKHttp() {    new Thread(new Runnable() {        @Override        public void run() {            try {                OkHttpClient client = new OkHttpClient();                Request request = new Request.Builder().url("http://bing.com").build();                Response response = client.newCall(request).execute();                String responseData = response.body().string();                showResponse(responseData);            } catch (Exception e) {                e.printStackTrace();            }        }    }).start();}

3.XML解析：

3.1 PULL:

private void parseXMLWithPull(String xmlData) {    try {        XmlPullParserFactory factory = XmlPullParserFactory.newInstance();        XmlPullParser xmlPullParser = factory.newPullParser();        xmlPullParser.setInput(new StringReader(xmlData));        int eventType = xmlPullParser.getEventType();        String id = "";        String name = "";        while (eventType != XmlPullParser.END_DOCUMENT) {            String nodeName = xmlPullParser.getName();            switch (eventType) {                case XmlPullParser.START_TAG:                    if ("id".equals(nodeName)){                        id = xmlPullParser.nextText();                    } else if ("name".equals(nodeName)){                    name = xmlPullParser.nextText();                    }                    break;               case XmlPullParser.END_TAG:                   if ("app".equals(nodeName)){                       Log.d("MainActivity","id is " + id);                       Log.d("MainActivity","name is " + name);                   }                   break;               default:                   break;            }            eventType = xmlPullParser.next();        }    } catch (Exception e) {            e.printStackTrace();        }}

3.2 SAX:

public class ContentHandler extends DefaultHandler {    private String nodeName;    private StringBuilder id;    private StringBuilder name;    @Override    public void startDocument() throws SAXException {        id = new StringBuilder();        name = new StringBuilder();    }    @Override    public void startElement(String uri, String localName, Attributes attributes) throws SAXException {        nodeName = localName;    }    @Override    public void characters(char[] ch,int start,int length) throws SAXException {        if ("id".equals(nodeName)) {            id.append(ch,start,length);        } else if ("name".equals(nodeName)) {            name.append(ch,start,length);        }    }    @Override    public void endElement(String uri,String localName,String qName) throws SAXException {            if ("app".equals(localName)) {                Log.d("ContentHandler","id is " + id);                Log.d("ContentHandler","name is " + name);                id.setLength(0);                name.setLength(0);            }    }    @Override    public void endDocument() throws SAXException{        super.endDocument();    }}

private void parseXMLWithSAX(String xmlData) {    try {        SAXParserFactory factory = SAXParserFactory.newInstance();        XMLReader xmlReader = factory.newSAXParser().getXMLReader();        ContentHandler handler = new ContentHandler();        xmlReader.setContentHandler(handler);        xmlReader.parse(new InputSource(new StringReader(xmlData)));    } catch (Exception e) {        e.printStackTrace();    }}

4.JSON解析：

4.1 JSONObject:

private void parseJSONWithJSONObject(String jsonData) {    try {        JSONArray jsonArray = new JSONArray(jsonData);        for (int i=0;i<jsonArray.length();i++) {            JSONObject jsonObject = jsonArray.getJSONObject(i);            String id = jsonObject.getString("id");            String name = jsonObject.getString("name");            Log.d("MainActivity","id is " + id);            Log.d("MainActivity","name is " + name);        }    }catch (Exception e) {        e.printStackTrace();    }}

4.2 GSON:

compile 'com.google.code.gson:gson:2.8'

private void parseJSONWithGSON(String jsonData) {    Gson gson = new Gson();    List<App> appList = gson.fromJson(jsonData,new TypeToken<List<App>>(){}.getRawType());    for (App app:appList) {        Log.d("MainActivity","id is " + app.getId());        Log.d("MainAcitvity","name is " + app.getName());    }}

5.封装网络操作：

public class HttpUtil {    public static void sendOkHttpRequest(String address,okhttp3.Callback callback) {        OkHttpClient client = new OkHttpClient();        Request request = new Request.Builder().url(address).build();        client.newCall(request).enqueue(callback);    }}

调用：

String address = "http://zcsj8.pe.hu";HttpUtil.sendOkHttpRequest(address,new okhttp3.Callback() {    @Override    public void onResponse(Call call, Response response) throws IOException {        String responsData = response.body().string();        showResponse(responsData);    }    @Override    public void onFailure(Call call,IOException e) {    }});