android json和httpget的使用

public class JsonActivity extends Activity {
    /** Called when the activity is first created. */
    private TextView tvJson;
    private Button btnJson;
    private Button btnJsonMulti;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        tvJson = (TextView) this.findViewById(R.id.tvJson);
        btnJson = (Button) this.findViewById(R.id.btnJson);
        btnJsonMulti = (Button) this.findViewById(R.id.btnJsonMulti);
        btnJson.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // url
                // String strUrl = "http://10.158.166.110:8080/AndroidServer/JsonServlet";
                String strUrl = ServerPageUtil.getStrUrl(UrlsOfServer.JSON_SINGER);
                //获得返回的Json字符串
                String strResult = connServerForResult(strUrl);
                //解析Json字符串
                parseJson(strResult);
            }
        });
        btnJsonMulti.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String strUrl = ServerPageUtil.getStrUrl(UrlsOfServer.JSON_SINGERS);
                String strResult = connServerForResult(strUrl);
                //获得多个Singer
                parseJsonMulti(strResult);
            }
        });
    }
    private String connServerForResult(String strUrl) {
        // HttpGet对象
        HttpGet httpRequest = new HttpGet(strUrl);
        String strResult = "";
        try {
            // HttpClient对象
            HttpClient httpClient = new DefaultHttpClient();
            // 获得HttpResponse对象
            HttpResponse httpResponse = httpClient.execute(httpRequest);
            if (httpResponse.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                // 取得返回的数据
                strResult = EntityUtils.toString(httpResponse.getEntity());
            }
        } catch (ClientProtocolException e) {
            tvJson.setText("protocol error");
            e.printStackTrace();
        } catch (IOException e) {
            tvJson.setText("IO error");
            e.printStackTrace();
        }
        return strResult;
    }
    // 普通Json数据解析
    private void parseJson(String strResult) {
        try {
            JSONObject jsonObj = new JSONObject(strResult).getJSONObject("singer");
            int id = jsonObj.getInt("id");
            String name = jsonObj.getString("name");
            String gender = jsonObj.getString("gender");
            tvJson.setText("ID号"+id + ", 姓名：" + name + ",性别：" + gender);
        } catch (JSONException e) {
            System.out.println("Json parse error");
            e.printStackTrace();
        }
    }
    //解析多个数据的Json
    private void parseJsonMulti(String strResult) {
        try {
            JSONArray jsonObjs = new JSONObject(strResult).getJSONArray("singers");
            String s = "";
            for(int i = 0; i < jsonObjs.length() ; i++){
                JSONObject jsonObj = ((JSONObject)jsonObjs.opt(i))
                .getJSONObject("singer");
                int id = jsonObj.getInt("id");
                String name = jsonObj.getString("name");
                String gender = jsonObj.getString("gender");
                s +=  "ID号"+id + ", 姓名：" + name + ",性别：" + gender+ "\n" ;
            }
            tvJson.setText(s);
        } catch (JSONException e) {
            System.out.println("Jsons parse error !");
            e.printStackTrace();
        }
    }
}