httpclient的简单使用

1、通过get请求后台，注意tomcat的编码设置成utf-8;    <Connector connectionTimeout="20000" port="8080" protocol="HTTP/1.1" redirectPort="8443" URIEncoding="UTF-8" />

/**
     * 发送 get请求
     */
    public static void get() {
        CloseableHttpClient httpclient = HttpClients.createDefault();
        try {
            //先将参数放入List，再对参数进行URL编码
            List<BasicNameValuePair> params = new LinkedList<BasicNameValuePair>();
            params.add(new BasicNameValuePair("get", "get请求哈哈哈")); 

            //对参数编码
            String param = URLEncodedUtils.format(params, "UTF-8");
            // 创建httpget.
            HttpGet httpget = new HttpGet("http://localhost:8080/HttpServleTest.html?"+param);  

            // 执行get请求.
            CloseableHttpResponse response = httpclient.execute(httpget);
            try {
                // 获取响应实体
                HttpEntity entity = response.getEntity();
                // 打印响应状态码
                System.out.println(response.getStatusLine().getStatusCode());
                if (entity != null) {
                    // 打印响应内容
                    System.out.println("Response content: " + EntityUtils.toString(entity,"UTF-8"));
                }
            } finally {
                response.close();
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            // 关闭连接,释放资源
            try {
                httpclient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }  

2.post请求

/**
     * 发送 post
     */
    public static void post() {
        // 创建默认的httpClient实例.
        CloseableHttpClient httpclient = HttpClients.createDefault();
        // 创建httppost
        HttpPost httppost = new HttpPost("http://localhost:8080/HttpServleTest.html");
        // 创建参数队列
        List<NameValuePair> formparams = new ArrayList<NameValuePair>();
        formparams.add(new BasicNameValuePair("post", "post请求哈哈哈"));
        UrlEncodedFormEntity uefEntity;
        try {
            uefEntity = new UrlEncodedFormEntity(formparams, "UTF-8");
            httppost.setEntity(uefEntity);
            CloseableHttpResponse response = httpclient.execute(httppost);
            try {
                HttpEntity entity = response.getEntity();
                if (entity != null) {
                    System.out.println("Response content: " + EntityUtils.toString(entity, "UTF-8"));
                }
            } finally {
                response.close();
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            // 关闭连接,释放资源
            try {
                httpclient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }  

3、后台服务程序和本案例代码下载地址：http://download.csdn.net/download/u013865056/9971496