Java实现Web工具类

r囧r小猫 2021-07-25 02:03 383阅读 0赞

# 一 点睛 #

我们常常需要利用web工具类发送get或post请求，在此提供一个工具类。

# 二 代码 #

package com.imooc.demo.common.util;
    
    import org.apache.http.*;
    import org.apache.http.client.HttpRequestRetryHandler;
    import org.apache.http.client.config.RequestConfig;
    import org.apache.http.client.entity.UrlEncodedFormEntity;
    import org.apache.http.client.methods.CloseableHttpResponse;
    import org.apache.http.client.methods.HttpPost;
    import org.apache.http.client.protocol.HttpClientContext;
    import org.apache.http.config.Registry;
    import org.apache.http.config.RegistryBuilder;
    import org.apache.http.conn.ConnectTimeoutException;
    import org.apache.http.conn.routing.HttpRoute;
    import org.apache.http.conn.socket.ConnectionSocketFactory;
    import org.apache.http.conn.socket.LayeredConnectionSocketFactory;
    import org.apache.http.conn.socket.PlainConnectionSocketFactory;
    import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
    import org.apache.http.entity.StringEntity;
    import org.apache.http.impl.client.CloseableHttpClient;
    import org.apache.http.impl.client.HttpClients;
    import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
    import org.apache.http.message.BasicNameValuePair;
    import org.apache.http.protocol.HttpContext;
    import org.apache.http.util.EntityUtils;
    
    import javax.net.ssl.SSLException;
    import javax.net.ssl.SSLHandshakeException;
    import java.io.IOException;
    import java.io.InputStream;
    import java.io.InterruptedIOException;
    import java.net.UnknownHostException;
    import java.nio.charset.Charset;
    import java.util.*;
    import java.util.Map.Entry;
    import java.util.concurrent.Executors;
    import java.util.concurrent.ScheduledExecutorService;
    import java.util.concurrent.TimeUnit;
    
    import org.apache.log4j.Logger;
    
    
    public final class WebUtils {
    
        private static Logger log = Logger.getLogger(WebUtils.class);
    
        private static final int CONNECT_TIMEOUT = Config.getHttpConnectTimeout(); // 设置连接建立的超时时间为3s
        private static final int SOCKET_TIMEOUT = Config.getHttpSocketTimeout();
        private static final int MAX_CONN = Config.getHttpMaxPoolSize(); // 最大连接数
        private static final int MAX_PRE_ROUTE = Config.getHttpMaxPoolSize();
        private static final int MAX_ROUTE = Config.getHttpMaxPoolSize();
    
        private static CloseableHttpClient httpClient; // 发送请求的客户端单例
        private static PoolingHttpClientConnectionManager manager; // 连接池管理类
        private static ScheduledExecutorService monitorExecutor;
    
        private final static Object syncLock = new Object(); // 相当于线程锁,用于线程安全
    
    
        /**
         * http post 请求
         *
         * @param url    请求地址
         * @param params 请求参数
         * @return String 返回结果
         * @throws Exception 异常
         */
        public static String post(String url, Map<String, String> params) throws Exception {
            CloseableHttpClient client = getHttpClient(url);
            String responseText = "";
            CloseableHttpResponse response = null;
            try {
                HttpPost method = new HttpPost(url);
                RequestConfig requestConfig = RequestConfig.custom().setConnectionRequestTimeout(CONNECT_TIMEOUT)
                        .setConnectTimeout(CONNECT_TIMEOUT).setSocketTimeout(SOCKET_TIMEOUT).build();
                method.setConfig(requestConfig);
                if (params != null) {
                    List<NameValuePair> paramList = new ArrayList<NameValuePair>();
                    for (Entry<String, String> param : params.entrySet()) {
                        NameValuePair pair = new BasicNameValuePair(param.getKey(), param.getValue());
                        paramList.add(pair);
                    }
                    method.setEntity(new UrlEncodedFormEntity(paramList, "UTF-8"));
                }
                response = client.execute(method, HttpClientContext.create());
                HttpEntity entity = response.getEntity();
                if (entity != null) {
                    responseText = EntityUtils.toString(entity);
                }
            } catch (Exception e) {
                throw e;
            } finally {
                try {
                    if (null != response) {
                        response.close();
                    }
                } catch (Exception e) {
                    throw e;
                }
            }
            return responseText;
        }
    
        /**
         * http post 请求
         *
         * @param url     请求地址
         * @param headers 请求头部
         * @param params  请求参数
         * @return String 返回结果
         * @throws Exception 异常
         */
        public static String post(String url, Map<String, String> headers, Map<String, String> params) throws Exception {
            CloseableHttpClient client = getHttpClient(url);
            String responseText = "";
            CloseableHttpResponse response = null;
            try {
                HttpPost method = new HttpPost(url);
                RequestConfig requestConfig = RequestConfig.custom().setConnectionRequestTimeout(CONNECT_TIMEOUT)
                        .setConnectTimeout(CONNECT_TIMEOUT).setSocketTimeout(SOCKET_TIMEOUT).build();
                method.setConfig(requestConfig);
                if (null != headers && !headers.isEmpty()) {
                    for (Entry<String, String> entry : headers.entrySet()) {
                        method.setHeader(entry.getKey(), entry.getValue());
                    }
                }
                if (params != null) {
                    List<NameValuePair> paramList = new ArrayList<NameValuePair>();
                    for (Entry<String, String> param : params.entrySet()) {
                        NameValuePair pair = new BasicNameValuePair(param.getKey(), param.getValue());
                        paramList.add(pair);
                    }
                    method.setEntity(new UrlEncodedFormEntity(paramList, "UTF-8"));
                }
                response = client.execute(method, HttpClientContext.create());
                HttpEntity entity = response.getEntity();
                if (entity != null) {
                    responseText = EntityUtils.toString(entity);
                }
            } catch (Exception e) {
                throw e;
            } finally {
                try {
                    if (null != response) {
                        response.close();
                    }
                } catch (Exception e) {
                    throw e;
                }
            }
            return responseText;
        }
    
        /**
         * http的post请求：通过流方式传数据
         *
         * @param uri  请求地址
         * @param data 请求数据
         * @return 返回结果
         */
        public static String post(String uri, String data) {
            log.info("请求数据：" + data);
            CloseableHttpClient httpClient = getHttpClient(uri);
            HttpPost method = new HttpPost(uri);
            RequestConfig requestConfig = RequestConfig.custom().setConnectionRequestTimeout(CONNECT_TIMEOUT)
                    .setConnectTimeout(CONNECT_TIMEOUT).setSocketTimeout(SOCKET_TIMEOUT).build();
            method.setConfig(requestConfig);
    
            String readContent = null;
            try {
                method.addHeader("Content-type", "application/xml; charset=ISO-8859-1");
                method.setHeader("Accept", "application/xml");
                method.setEntity(new StringEntity(data, Charset.forName("utf-8")));
                HttpResponse response = httpClient.execute(method, HttpClientContext.create());
                int statusCode = response.getStatusLine().getStatusCode();
                if (statusCode != 200) {
                    return "failed";
                }
                HttpEntity entity = response.getEntity();
                InputStream in = entity.getContent();
                int count = 0;
                while (count == 0) {
                    count = Integer.parseInt("" + entity.getContentLength());// in.available();
                }
                if (count <= 0) {
                    return EntityUtils.toString(entity);
                }
                byte[] bytes = new byte[count];
                int readCount = 0; // 已经成功读取的字节的个数
                while (readCount <= count) {
                    if (readCount == count) {
                        break;
                    }
                    readCount += in.read(bytes, readCount, count - readCount);
                }
                readContent = new String(bytes, 0, readCount, "UTF-8");
                log.info("Get Response Content():\n " + readContent);
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                try {
                    httpClient.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return readContent;
        }
    
        /**
         * 关闭连接池
         */
        public static void closeConnectionPool() {
            try {
                httpClient.close();
                manager.close();
                monitorExecutor.shutdown();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    
        /**
         * 把map转为xml
         *
         * @param parameters map参数
         * @return String XML字符串
         */
        public static String parseXML(Map<String, String> parameters) {
            StringBuffer sb = new StringBuffer();
            sb.append("<xml>");
            Iterator<Entry<String, String>> itor = parameters.entrySet().iterator();
            while (itor.hasNext()) {
                Entry<String, String> entry = itor.next();
                String k = entry.getKey();
                String v = entry.getValue();
                if (null != v && !"".equals(v) && !"appkey".equals(k)) {
                    sb.append("<" + k + ">" + parameters.get(k) + "</" + k + ">\n");
                }
            }
            sb.append("</xml>");
            return sb.toString();
        }
    
        /**
         * 从URL中提取所有的参数，存到map中
         *
         * @param url 请求地址
         * @return 提取后的Map参数
         */
        public static Map<String, String> splitUrlQuery(String url) {
            Map<String, String> result = new HashMap<String, String>();
            String[] pairs = url.split("&");
            if (pairs != null && pairs.length > 0) {
                for (String pair : pairs) {
                    String[] param = pair.split("=", 2);
                    if (param != null && param.length == 2) {
                        result.put(param[0], param[1]);
                    }
                }
            }
            return result;
        }
    
        /**
         * 功能描述：获得请求的客户端
         *
         * @author cakin
         * @date 2020/8/21
         * @param url 请求地址
         * @return CloseableHttpClient 请求客户端
         */
        public static CloseableHttpClient getHttpClient(String url) {
            int port = 80;
            String hostName = url.split("/")[2];
            if (hostName.contains(":")) {
                String[] args = hostName.split(":");
                hostName = args[0];
                port = Integer.parseInt(args[1]);
            }
    
            if (httpClient == null) {
                // 多线程下多个线程同时调用getHttpClient容易导致重复创建httpClient对象的问题,所以加上了同步锁
                synchronized (syncLock) {
                    if (httpClient == null) {
                        httpClient = createHttpClient(hostName, port);
                        // 开启监控线程,对异常和空闲线程进行关闭
                        monitorExecutor = Executors.newScheduledThreadPool(1);
                        monitorExecutor.scheduleAtFixedRate(new TimerTask() {
                            @Override
                            public void run() {
                                // 关闭异常连接
                                manager.closeExpiredConnections();
                                // 关闭5s空闲的连接
                                manager.closeIdleConnections(Config.getHttpIdelTimeout(), TimeUnit.MILLISECONDS);
                            }
                        }, Config.getHttpMonitorInterval(), Config.getHttpMonitorInterval(), TimeUnit.MILLISECONDS);
                    }
                }
            }
            return httpClient;
        }
    
        /**
         * 根据host和port构建httpclient实例
         *
         * @param host 要访问的域名
         * @param port 要访问的端口
         * @return CloseableHttpClient http客户端
         */
        public static CloseableHttpClient createHttpClient(String host, int port) {
            ConnectionSocketFactory plainSocketFactory = PlainConnectionSocketFactory.getSocketFactory();
            LayeredConnectionSocketFactory sslSocketFactory = SSLConnectionSocketFactory.getSocketFactory();
            Registry<ConnectionSocketFactory> registry = RegistryBuilder.<ConnectionSocketFactory>create()
                    .register("http", plainSocketFactory).register("https", sslSocketFactory).build();
    
            manager = new PoolingHttpClientConnectionManager(registry);
            // 设置连接参数
            manager.setMaxTotal(MAX_CONN); // 最大连接数
            manager.setDefaultMaxPerRoute(MAX_PRE_ROUTE); // 路由最大连接数
    
            HttpHost httpHost = new HttpHost(host, port);
            manager.setMaxPerRoute(new HttpRoute(httpHost), MAX_ROUTE);
    
            // 请求失败时,进行请求重试
            HttpRequestRetryHandler handler = new HttpRequestRetryHandler() {
                @Override
                public boolean retryRequest(IOException e, int i, HttpContext httpContext) {
                    if (i > 3) {
                        // 重试超过3次,放弃请求
                        log.error("retry has more than 3 time, give up request");
                        return false;
                    }
                    if (e instanceof NoHttpResponseException) {
                        // 服务器没有响应,可能是服务器断开了连接,应该重试
                        log.error("receive no response from server, retry");
                        return true;
                    }
                    if (e instanceof SSLHandshakeException) {
                        // SSL握手异常
                        log.error("SSL hand shake exception");
                        return false;
                    }
                    if (e instanceof InterruptedIOException) {
                        // 超时
                        log.error("InterruptedIOException");
                        return false;
                    }
                    if (e instanceof UnknownHostException) {
                        // 服务器不可达
                        log.error("server host unknown");
                        return false;
                    }
                    if (e instanceof ConnectTimeoutException) {
                        // 连接超时
                        log.error("Connection Time out");
                        return false;
                    }
                    if (e instanceof SSLException) {
                        log.error("SSLException");
                        return false;
                    }
    
                    HttpClientContext context = HttpClientContext.adapt(httpContext);
                    HttpRequest request = context.getRequest();
                    if (!(request instanceof HttpEntityEnclosingRequest)) {
                        // 如果请求不是关闭连接的请求
                        return true;
                    }
                    return false;
                }
            };
            return HttpClients.custom().setConnectionManager(manager).setRetryHandler(handler).build();
        }
    
        /**
         * 功能描述：测试post请求
         *
         * @author cakin
         * @date 2020/8/21
         * @param args 参数
         */
        public static void main(String[] args) throws Exception {
            String url = "http://120.76.132.142:8088/gateway";
            Map<String, String> data = new HashMap<>();
            data.put("charset","UTF-8");
            data.put("method" , "invoice.getInvoice");
            data.put("params" , "{\"beginDate\":\"2020-01-01 00:00:00\",\"endDate\":\"2040-01-01 00:00:00\",\"invoiceNo\":\"2020082026693\",\"pageNo\":1}");
            data.put("app_id","200714008366");
            data.put("sign_type", "MD5");
            data.put("version" , "1.0.0");
            data.put("timestamp" , String.valueOf(System.currentTimeMillis()));
            // 数字签名
            String dataStr = SignatureUtils.createLinkString(SignatureUtils.filter(data));
            String salt = "xxxxxxxxxx";
            String sign = Md5.encrypt(dataStr, salt, "UTF-8");
            data.put("sign", sign);
            String rsp = WebUtils.post(url, data);
            log.info(rsp);
        }
    }
    
    /**
     * @className: WebUtils
     * @description: 配置类
     * @date: 2020/8/21
     * @author: cakin
     */
    class Config {
        static int httpConnectTimeout = 3000; // 设置连接建立的超时时间为3s
        static int httpSocketTimeout = 60000;
        static int httpMaxPoolSize = 2000; // 最大连接数
        static int httpMonitorInterval = 3000;
        static int httpIdelTimeout = 2000;
    
        public static int getHttpIdelTimeout() {
            return httpIdelTimeout;
        }
    
        public static int getHttpSocketTimeout() {
            return httpSocketTimeout;
        }
    
        public static int getHttpMaxPoolSize() {
            return httpMaxPoolSize;
        }
    
        public static int getHttpMonitorInterval() {
            return httpMonitorInterval;
        }
    
        public static int getHttpConnectTimeout() {
            return httpConnectTimeout;
        }
    }

# 三 测试 #

2020-08-21 11:55:17 INFO  WebUtils:398 - \{"msg":"处理成功","code":"SUCCESS","data":\{.............\}