《转》Java模拟HTTP的Get和Post请求

import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpMethod;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.URIException;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.commons.httpclient.params.HttpMethodParams;
import org.apache.commons.httpclient.util.URIUtil;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Map;

/**
* HTTP工具箱
*
* @author leizhimin 2009-6-19 16:36:18
*/
public final class HttpTookit {
        private static Log log = LogFactory.getLog(HttpTookit.class);

        /**
         * 执行一个HTTP GET请求，返回请求响应的HTML
         *
         * @param url                 请求的URL地址
         * @param queryString 请求的查询参数,可以为null
         * @param charset         字符集
         * @param pretty            是否美化
         * @return 返回请求响应的HTML
         */
        public static String doGet(String url, String queryString, String charset, boolean pretty) {
                StringBuffer response = new StringBuffer();
                HttpClient client = new HttpClient();
                HttpMethod method = new GetMethod(url);
                try {
                        if (StringUtils.isNotBlank(queryString))
                                //对get请求参数做了http请求默认编码，好像没有任何问题，汉字编码后，就成为%式样的字符串
                                method.setQueryString(URIUtil.encodeQuery(queryString));
                        client.executeMethod(method);
                        if (method.getStatusCode() == HttpStatus.SC_OK) {
                                BufferedReader reader = new BufferedReader(new InputStreamReader(method.getResponseBodyAsStream(), charset));
                                String line;
                                while ((line = reader.readLine()) != null) {
                                        if (pretty)
                                                response.append(line).append(System.getProperty("line.separator"));
                                        else
                                                response.append(line);
                                }
                                reader.close();
                        }
                } catch (URIException e) {
                        log.error("执行HTTP Get请求时，编码查询字符串“" + queryString + "”发生异常！", e);
                } catch (IOException e) {
                        log.error("执行HTTP Get请求" + url + "时，发生异常！", e);
                } finally {
                        method.releaseConnection();
                }
                return response.toString();
        }

        /**
         * 执行一个HTTP POST请求，返回请求响应的HTML
         *
         * @param url         请求的URL地址
         * @param params    请求的查询参数,可以为null
         * @param charset 字符集
         * @return 返回请求响应的HTML
         */
        public static String doPost(String url, Map<String, String> params, String charset) {
                StringBuffer response = new StringBuffer();
                HttpClient client = new HttpClient();
                PostMethod method = new PostMethod(url);
                //设置Http Post数据
                if (params != null) {
                		NameValuePair[] data = new NameValuePair[5];
                		int i=0;
                        HttpMethodParams p = new HttpMethodParams();
                        for (Map.Entry<String, String> entry : params.entrySet()) {
                        		data[i]=new NameValuePair(entry.getKey(), entry.getValue());
                        		i++;
                        }
                        method.setRequestBody(data);
                }
                try {
                        client.executeMethod(method);
                        if (method.getStatusCode() == HttpStatus.SC_OK) {
                        	System.out.println("OK");
                        }else{
                        	System.out.println(method.getStatusCode());
                        }
                } catch (IOException e) {
                        log.error("执行HTTP Post请求" + url + "时，发生异常！", e);
                } finally {
                        method.releaseConnection();
                }
                return response.toString();
        }

        public static void main(String[] args) {
                String y = doGet("http://video.sina.com.cn/life/tips.html", null, "GBK", true);
                System.out.println(y);
        }
}

 另外，将查看Java平台环境的代码给出来，很常用！

        public static void main(String[] args) {
                Properties p = System.getProperties();
                for (Map.Entry<Object, Object> entry : p.entrySet()) {
                        System.out.println(entry.getKey() + " = " + entry.getValue());
                }
        }

 用到的包随文上传了。这个用的是HttpClient 3.1 版本