JAVA_GET请求URL

import java.io.IOException;

import net.sf.json.JSONObject;

import org.apache.commons.httpclient.DefaultHttpMethodRetryHandler;
import org.apache.commons.httpclient.Header;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpException;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.params.HttpMethodParams;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;

public class TestGetRequest {

    /**
     * @param args
     */
    public static void main(String[] args) {

        String url = "http://www.ecmwf.int/plots/get-map/";
        String param = "{"product":{"product":{"name":"public_plots","package":"medium"},"values":{"time":["2016032012",48,"2016032212"],"parameter":"Wind 850 and mslp","area":"Asia"}}}";
        System.out.println(param);
        JSONObject object = JSONObject.fromObject(param);
        JSONObject result = doPost(url, object);
        System.out.println(result);
        JSONObject imgResult = (JSONObject) result.get("result");
        System.out.println(imgResult.get("url"));
    }

    public static String doGet(String url, String charset) throws Exception {
        /*
         * 使用 GetMethod 来访问一个 URL 对应的网页,实现步骤: 1:生成一个 HttpClinet 对象并设置相应的参数。
         * 2:生成一个 GetMethod 对象并设置响应的参数。 3:用 HttpClinet 生成的对象来执行 GetMethod 生成的Get
         * 方法。 4:处理响应状态码。 5:若响应正常，处理 HTTP 响应内容。 6:释放连接。
         */
        /* 1 生成 HttpClinet 对象并设置参数 */
        HttpClient httpClient = new HttpClient();
        // 设置 Http 连接超时为5秒
        httpClient.getHttpConnectionManager().getParams().setConnectionTimeout(
                5000);
        /* 2 生成 GetMethod 对象并设置参数 */
        GetMethod getMethod = new GetMethod(url);
        // 设置 get 请求超时为 5 秒
        getMethod.getParams().setParameter(HttpMethodParams.SO_TIMEOUT, 5000);
        // 设置请求重试处理，用的是默认的重试处理：请求三次
        getMethod.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,
                new DefaultHttpMethodRetryHandler());
        String response = "";
        /* 3 执行 HTTP GET 请求 */
        try {
            int statusCode = httpClient.executeMethod(getMethod);
            /* 4 判断访问的状态码 */
            if (statusCode != HttpStatus.SC_OK) {
                System.err.println("请求出错: " + getMethod.getStatusLine());
            }
            /* 5 处理 HTTP 响应内容 */
            // HTTP响应头部信息，这里简单打印
            Header[] headers = getMethod.getResponseHeaders();
            for (Header h : headers)
                System.out
                        .println(h.getName() + "------------ " + h.getValue());
            // 读取 HTTP 响应内容，这里简单打印网页内容
            byte[] responseBody = getMethod.getResponseBody();// 读取为字节数组
            response = new String(responseBody, charset);
            System.out.println("----------response:" + response);
            // 读取为 InputStream，在网页内容数据量大时候推荐使用
            // InputStream response = getMethod.getResponseBodyAsStream();
        } catch (HttpException e) {
            // 发生致命的异常，可能是协议不对或者返回的内容有问题
            System.out.println("请检查输入的URL!");
            e.printStackTrace();
        } catch (IOException e) {
            // 发生网络异常
            System.out.println("发生网络异常!");
            e.printStackTrace();
        } finally {
            /* 6 .释放连接 */
            getMethod.releaseConnection();
        }
        return response;
    }

    public static JSONObject doPost(String url, JSONObject json) {
        DefaultHttpClient client = new DefaultHttpClient();
        HttpPost post = new HttpPost(url);
        JSONObject response = null;
        try {
            StringEntity s = new StringEntity(json.toString());
            s.setContentEncoding("UTF-8");
            s.setContentType("application/json");// 发送json数据需要设置contentType
            post.setEntity(s);
            HttpResponse res = client.execute(post);
            if (res.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                HttpEntity entity = res.getEntity();
                String result = EntityUtils.toString(res.getEntity());// 返回json格式：
                response = JSONObject.fromObject(result);
            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        return response;
    }

}