一，httpclient的理解
httpcliet就是模仿浏览器在服务器内部从一个项目调用另一个项目的技术。比如说调用接口等。
HttpClient 是 Apache Jakarta Common 下的子项目，用来提供高效的、最新的、功能丰富的支持 HTTP 协议的客户端编程工具包，并且它支持 HTTP 协议最新的版本和建议。
二，httpclient的使用方法
1.1，jar包
需要把httpclient的jar包添加到工程中。只需要在工程中添加httpclient的依赖。
1.2，使用方法
1.2.1，get无参请求
@Test
public void doGet() throws Exception {
//创建一个httpclient对象
CloseableHttpClient httpClient = HttpClients.createDefault();
//创建一个GET对象
HttpGet get = new HttpGet("http://www.sogou.com");
//执行请求
CloseableHttpResponse response = httpClient.execute(get);
//取响应的结果
int statusCode = response.getStatusLine().getStatusCode();
System.out.println(statusCode);
HttpEntity entity = response.getEntity();
String string = EntityUtils.toString(entity, "utf-8");
System.out.println(string);
//关闭httpclient
response.close();
httpClient.close();
}1.2.2，get带参请求
@Test
public void doGetWithParam() throws Exception{
//创建一个httpclient对象
CloseableHttpClient httpClient = HttpClients.createDefault();
//创建一个uri对象
URIBuilder uriBuilder = new URIBuilder("http://www.sogou.com/web");
uriBuilder.addParameter("query", "花千骨");
HttpGet get = new HttpGet(uriBuilder.build());
//执行请求
CloseableHttpResponse response = httpClient.execute(get);
//取响应的结果
int statusCode = response.getStatusLine().getStatusCode();
System.out.println(statusCode);
HttpEntity entity = response.getEntity();
String string = EntityUtils.toString(entity, "utf-8");
System.out.println(string);
//关闭httpclient
response.close();
httpClient.close();
}1.2.3，post无参请求
@Test
public void doPost() throws Exception {
CloseableHttpClient httpClient = HttpClients.createDefault();
//创建一个post对象
HttpPost post = new HttpPost("http://localhost:8082/httpclient/post.action");
//执行post请求
CloseableHttpResponse response = httpClient.execute(post);
String string = EntityUtils.toString(response.getEntity());
System.out.println(string);
response.close();
httpClient.close();
}1.2.4，post带参请求
@Test
public void doPostWithParam() throws Exception{
CloseableHttpClient httpClient = HttpClients.createDefault();
//创建一个post对象
HttpPost post = new HttpPost("http://localhost:8082/httpclient/post.action");
//创建一个Entity。模拟一个表单
List<NameValuePair> kvList = new ArrayList<>();
kvList.add(new BasicNameValuePair("username", "张三"));
kvList.add(new BasicNameValuePair("password", "123"));
//包装成一个Entity对象
StringEntity entity = new UrlEncodedFormEntity(kvList, "utf-8");
//设置请求的内容
post.setEntity(entity);
//执行post请求
CloseableHttpResponse response = httpClient.execute(post);
String string = EntityUtils.toString(response.getEntity());
System.out.println(string);
response.close();
httpClient.close();
}三，httpclient的案例讲解
3.1，httpclient的工具类httpclientutil
package com.http;
import java.io.ByteArrayOutputStream;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InterruptedIOException;
import java.io.UnsupportedEncodingException;
import java.net.SocketException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.UnknownHostException;
import java.security.KeyManagementException;
import java.security.NoSuchAlgorithmException;
import java.security.cert.X509Certificate;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.zip.GZIPInputStream;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLException;
import javax.net.ssl.SSLHandshakeException;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.http.Header;
import org.apache.http.HttpEntity;
import org.apache.http.HttpEntityEnclosingRequest;
import org.apache.http.HttpHost;
import org.apache.http.HttpRequest;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.NoHttpResponseException;
import org.apache.http.ParseException;
import org.apache.http.ProtocolException;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.CookieStore;
import org.apache.http.client.HttpRequestRetryHandler;
import org.apache.http.client.config.CookieSpecs;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.config.RequestConfig.Builder;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.protocol.HttpClientContext;
import org.apache.http.conn.ConnectTimeoutException;
import org.apache.http.conn.HttpHostConnectException;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.cookie.Cookie;
import org.apache.http.entity.ByteArrayEntity;
import org.apache.http.impl.client.BasicCookieStore;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.DefaultRedirectStrategy;
import org.apache.http.impl.client.HttpClientBuilder;
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.ByteArrayBuffer;
import org.apache.http.util.EntityUtils;
/**
* HttpClient工具封装类，Post，Get请求，代理请求
* 作者：<br>
* 版本：1.0<br>
* 创建日期：下午9:21:00<br>
*/
public class HttpClientUtil {
/***连接超时时间*/
private Integer connectTimeout =60*1000;
private Integer socketTimeout =180*1000;
private CloseableHttpClient httpClient = null;
private CookieStore cookieStore = new BasicCookieStore();
/** 代理请求 */
public HttpClientUtil(String proxyHost, int proxyPort) {
this(proxyHost, proxyPort, -1, -1, 0, 0, true);
}
/** 默认*/
public HttpClientUtil() {
this(null, 0, -1, -1, 0, 0, true);
}
/** 进行请求无代理设置连接时间 */
public HttpClientUtil(int socketTimeout, int connectTimeout) {
this(null, 0, socketTimeout, connectTimeout, 0, 0, true);
}
/**
*
* @param proxyHost 代理主机地址
* @param proxyPort 代理端口
* @param socketTimeout
* @param connectTimeout
* @param route
* @param maxTotal
* @param followRedirect
*/
public HttpClientUtil(String proxyHost, int proxyPort, int socketTimeout, int connectTimeout, int route, int maxTotal, boolean followRedirect){
Builder builder = RequestConfig.custom();
builder.setCookieSpec(CookieSpecs.BROWSER_COMPATIBILITY);
if (followRedirect) {
builder.setCircularRedirectsAllowed(true);
builder.setMaxRedirects(100);
}
if (StringUtils.isNotBlank(proxyHost) && proxyPort > 0) {
builder.setProxy(new HttpHost(proxyHost, proxyPort));
}
//设置连接时间
if (socketTimeout != -1) {
this.socketTimeout = socketTimeout;
}
builder.setSocketTimeout(this.socketTimeout);
if (connectTimeout != -1) {
this.connectTimeout = connectTimeout;
}
builder.setConnectTimeout(this.connectTimeout);
builder.setConnectionRequestTimeout(this.connectTimeout);
RequestConfig requestConfig = builder.build();
init(requestConfig, route, maxTotal);
}
private void init(RequestConfig requestConfig, int route, int maxTotal) {
X509TrustManager x509mgr = new X509TrustManager() {
@Override
public void checkClientTrusted(X509Certificate[] xcs, String string) {
}
@Override
public void checkServerTrusted(X509Certificate[] xcs, String string) {
}
@Override
public X509Certificate[] getAcceptedIssuers() {
return null;
}
};
SSLContext sslContext = null;
try {
sslContext = SSLContext.getInstance("TLS");
} catch (NoSuchAlgorithmException e1) {
e1.printStackTrace();
}
try {
sslContext.init(null, new TrustManager[] { x509mgr }, null);
} catch (KeyManagementException e) {
e.printStackTrace();
}
SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslContext, SSLConnectionSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);
HttpRequestRetryHandler httpRequestRetryHandler = new HttpRequestRetryHandler() {
@Override
public boolean retryRequest(IOException exception, int executionCount, HttpContext context) {
if (executionCount >= 5) {// 如果已经重试了5次，就放弃
return false;
}
if (exception instanceof NoHttpResponseException) {// 如果服务器丢掉了连接，那么就重试
return true;
}
if (exception instanceof SSLHandshakeException) {// 不要重试SSL握手异常
return false;
}
if (exception instanceof InterruptedIOException) {// 超时
return false;
}
if (exception instanceof UnknownHostException) {// 目标服务器不可达
return false;
}
if (exception instanceof ConnectTimeoutException) {// 连接被拒绝
return false;
}
if (exception instanceof SSLException) {// ssl握手异常
return false;
}
// 2016-03-09针对broken pipe的问题做处理
if (exception instanceof SocketException) {
return true;
}
HttpClientContext clientContext = HttpClientContext.adapt(context);
HttpRequest request = clientContext.getRequest();
// 如果请求是幂等的，就再次尝试
if (!(request instanceof HttpEntityEnclosingRequest)) {
return true;
}
return false;
}
};
DefaultRedirectStrategy redirectStrategy = new DefaultRedirectStrategy() {
public boolean isRedirected(HttpRequest request, HttpResponse response, HttpContext context) {
boolean isRedirect = false;
try {
isRedirect = super.isRedirected(request, response, context);
} catch (ProtocolException e) {
e.printStackTrace();
}
if (!isRedirect) {
int responseCode = response.getStatusLine().getStatusCode();
if (responseCode == 301 || responseCode == 302) {
return true;
}
}
return isRedirect;
}
@Override
protected URI createLocationURI(String location) throws ProtocolException {
location = location.replace("|", "%7C");
return super.createLocationURI(location);
}
};
HttpClientBuilder httpClientBuilder = HttpClients.custom();
httpClientBuilder.setDefaultRequestConfig(requestConfig);
if (route > 0 && maxTotal > 0) {
PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
connManager.setDefaultMaxPerRoute(route);
connManager.setMaxTotal(maxTotal);
httpClientBuilder.setConnectionManager(connManager);
}
httpClientBuilder.setSSLSocketFactory(sslsf);
httpClientBuilder.setDefaultCookieStore(cookieStore);
httpClientBuilder.setRedirectStrategy(redirectStrategy);
httpClientBuilder.setRetryHandler(httpRequestRetryHandler);
httpClient = httpClientBuilder.build();
}
public Response sendRequest(Request request) throws Exception {
// request.setHeader("Accept",
// "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
// request.setHeader("Accept-Encoding", "gzip, deflate");
if (request.getHeader("User-Agent") == null) {
request.setHeader("User-Agent", "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:24.0) Gecko/20100101 Firefox/24.0");
}
request.setHeader("Accept-Language", "zh-cn,zh;q=0.8,en-us;q=0.5,en;q=0.3");
request.setHeader("Connection", "keep-alive");
// logger.debug("发送请求:" + request);
String method = request.getProperty("method").toLowerCase();
String url = request.getProperty("url");
Map<String, String> headers = request.getHeaders();
Map<String, String> params = request.getParams();
List<NameValuePair> formParams = new ArrayList<NameValuePair>();
if (params != null && params.size() != 0) {
formParams = new ArrayList<NameValuePair>();
for (Entry<String, String> entry : params.entrySet()) {
formParams.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
}
}
Response response = null;
if ("post".equals(method)) {
byte[] postData = request.getPostData();
if (postData != null) {
response = post(url, postData, headers);
} else {
response = post(url, formParams, headers);
}
} else if ("get".equals(method)) {
response = get(url, formParams, headers);
}
return response;
}
/**
* Get请求
*
* @param url
* @param params
* @return
*/
public Response get(String url, List<NameValuePair> params, Map<String, String> headers) {
Response response = new Response();
try {
// Get请求
HttpGet httpGet = new HttpGet(url);
String encoding = "utf-8";
// 设置头
if (headers != null && headers.size() != 0) {
for (Entry<String, String> entry : headers.entrySet()) {
httpGet.setHeader(entry.getKey(), entry.getValue());
}
String contentType = headers.get("Content-Type");
if (StringUtils.isNotBlank(contentType)) {
if (matcher(contentType, "(charset)\\s?=\\s?(gbk)")) {
encoding = "gbk";
} else if (matcher(contentType, "(charset)\\s?=\\s?(gb2312)")) {
encoding = "gb2312";
}
}
}
// 设置参数,如果url上已经有了问号，就不附加参数
if (params != null && params.size() > 0) {
if (httpGet.getURI().toString().indexOf("?") == -1) {
String str = EntityUtils.toString(new UrlEncodedFormEntity(params, encoding));
httpGet.setURI(new URI(httpGet.getURI().toString() + "?" + str));
} else {
String str = EntityUtils.toString(new UrlEncodedFormEntity(params, encoding));
httpGet.setURI(new URI(httpGet.getURI().toString() + "&" + str));
}
}
// 发送请求
CloseableHttpResponse httpResponse = httpClient.execute(httpGet);
try {
int statusCode = httpResponse.getStatusLine().getStatusCode();
response.setStatusCode(statusCode);
ByteArrayOutputStream byteOut = new ByteArrayOutputStream();
// 获取返回数据
HttpEntity entity = httpResponse.getEntity();
Header[] responseHeaders = httpResponse.getAllHeaders();
for (Header header : responseHeaders) {
response.setHeader(header.getName(), header.getValue());
}
Header header = entity.getContentEncoding();
if (header != null && header.getValue().toLowerCase().equals("gzip")) {
byte[] bytes = IOUtils.toByteArray(new GZIPInputStream(entity.getContent()));
response.setContent(bytes);
} else {
byte[] bytes = getData(entity);
response.setContent(bytes);
}
return response;
} finally {
httpResponse.close();
}
} catch (ConnectTimeoutException e) {
} catch (HttpHostConnectException e) {
} catch (ParseException e) {
} catch (UnsupportedEncodingException e) {
} catch (IOException e) {
} catch (URISyntaxException e) {
} catch (Exception e) {
}
return null;
}
/**
* // Post请求
*
* @param url
* @param params
* @return
*/
public Response post(String url, byte[] data, Map<String, String> headers) {
Response response = new Response();
try {
// Post请求
HttpPost httpPost = new HttpPost(url);
// 设置头
if (headers != null && headers.size() != 0) {
for (Entry<String, String> entry : headers.entrySet()) {
httpPost.setHeader(entry.getKey(), entry.getValue());
}
}
// 设置参数
httpPost.setEntity(new ByteArrayEntity(data));
// 发送请求
CloseableHttpResponse httpResponse = httpClient.execute(httpPost);
try {
int statusCode = httpResponse.getStatusLine().getStatusCode();
response.setStatusCode(statusCode);
// 获取返回数据
HttpEntity entity = httpResponse.getEntity();
Header header = entity.getContentEncoding();
if (header != null && header.getValue().toLowerCase().equals("gzip")) {
byte[] bytes = IOUtils.toByteArray(new GZIPInputStream(entity.getContent()));
response.setContent(bytes);
} else {
byte[] bytes = EntityUtils.toByteArray(entity);
response.setContent(bytes);
}
return response;
} finally {
httpResponse.close();
}
} catch (ConnectTimeoutException e) {
} catch (HttpHostConnectException e) {
} catch (UnsupportedEncodingException e) {
} catch (ClientProtocolException e) {
} catch (ParseException e) {
} catch (IOException e) {
} catch (Exception e) {
}
return null;
}
private byte[] getData(HttpEntity entity) throws IOException {
if (entity == null) {
throw new IllegalArgumentException("HTTP entity may not be null");
}
InputStream inputStream = entity.getContent();
if (inputStream == null) {
return null;
}
try {
if (entity.getContentLength() > Integer.MAX_VALUE) {
throw new IllegalArgumentException("HTTP entity too large to be buffered in memory");
}
int i = (int) entity.getContentLength();
if (i < 0) {
i = 4096;
}
ByteArrayBuffer buffer = new ByteArrayBuffer(i);
byte[] tmp = new byte[1024];
int l = -1;
try {
while ((l = inputStream.read(tmp)) != -1) {
buffer.append(tmp, 0, l);
}
} catch (EOFException e) {
buffer.clear();
// 针对于以没有结束符的做fix处理,减小缓存,并进行异常处理,忽略最后不能获取的数据
tmp = new byte[32];
try {
while ((l = inputStream.read(tmp)) != 1) {
buffer.append(tmp, 0, l);
}
} catch (EOFException e2) {
}
}
// TODO 查明具体没有返回的原因
byte[] byteArray = buffer.toByteArray();
if (byteArray == null || byteArray.length == 0) {
return buffer.buffer();
}
return byteArray;
} finally {
inputStream.close();
}
}
/**
* // Post请求
*
* @param url
* @param params
* @return
*/
public Response post(String url, List<NameValuePair> params, Map<String, String> headers) {
Response response = new Response();
try {
// Post请求
HttpPost httpPost = new HttpPost(url);
String encoding = "utf-8";
// 设置头
if (headers != null && headers.size() != 0) {
for (Entry<String, String> entry : headers.entrySet()) {
httpPost.setHeader(entry.getKey(), entry.getValue());
}
String contentType = headers.get("Content-Type");
if (StringUtils.isNotBlank(contentType)) {
if (matcher(contentType, "(charset)\\s?=\\s?(gbk)")) {
encoding = "gbk";
} else if (matcher(contentType, "(charset)\\s?=\\s?(gb2312)")) {
encoding = "gb2312";
}
}
}
// 设置参数
if (params != null && params.size() > 0) {
httpPost.setEntity(new UrlEncodedFormEntity(params, encoding));
}
// 发送请求
CloseableHttpResponse httpResponse = httpClient.execute(httpPost);
try {
int statusCode = httpResponse.getStatusLine().getStatusCode();
response.setStatusCode(statusCode);
// 获取返回数据
HttpEntity entity = httpResponse.getEntity();
Header header = entity.getContentEncoding();
if (header != null && header.getValue().toLowerCase().equals("gzip")) {
byte[] data = IOUtils.toByteArray(new GZIPInputStream(entity.getContent()));
response.setContent(data);
} else {
byte[] data = getData(entity);
response.setContent(data);
}
return response;
} finally {
httpResponse.close();
}
} catch (ConnectTimeoutException e) {
} catch (HttpHostConnectException e) {
} catch (UnsupportedEncodingException e) {
} catch (ClientProtocolException e) {
} catch (ParseException e) {
} catch (IOException e) {
} catch (Exception e) {
}
return null;
}
/**
* 获取Response内容字符集
*
* @param response
* @return
*/
public String getContentCharset(HttpResponse response) {
String charset = "ISO_8859-1";
Header header = response.getEntity().getContentType();
if (header != null) {
String s = header.getValue();
if (matcher(s, "(charset)\\s?=\\s?(utf-?8)")) {
charset = "utf-8";
} else if (matcher(s, "(charset)\\s?=\\s?(gbk)")) {
charset = "gbk";
} else if (matcher(s, "(charset)\\s?=\\s?(gb2312)")) {
charset = "gb2312";
}
}
Header encoding = response.getEntity().getContentEncoding();
return charset;
}
/**
* 正则匹配
*
* @param s
* @param pattern
* @return
*/
private boolean matcher(String s, String pattern) {
Pattern p = Pattern.compile(pattern, Pattern.CASE_INSENSITIVE + Pattern.UNICODE_CASE);
Matcher matcher = p.matcher(s);
if (matcher.find()) {
return true;
} else {
return false;
}
}
public Integer getConnectTimeout() {
return connectTimeout;
}
public void setConnectTimeout(Integer connectTimeout) {
this.connectTimeout = connectTimeout;
}
public Integer getSocketTimeout() {
return socketTimeout;
}
public void setSocketTimeout(Integer socketTimeout) {
this.socketTimeout = socketTimeout;
}
public CloseableHttpClient getHttpClient() {
return httpClient;
}
public void setHttpClient(CloseableHttpClient httpClient) {
this.httpClient = httpClient;
}
public CookieStore getCookieStore() {
return cookieStore;
}
public void setCookieStore(CookieStore cookieStore) {
for(Cookie cookie:cookieStore.getCookies()){
this.cookieStore.addCookie(cookie);
}
}
}3.2， resource的property的文件
REST_BASE_URL=http://192.168.25.136:8080/rest REST_INDEX_AD_URL=/content/list/89
3.3，类中的调用
public class ContentServiceImpl implements ContentService {
@Value("${REST_BASE_URL}")
private String REST_BASE_URL;
@Value("${REST_INDEX_AD_URL}")
private String REST_INDEX_AD_URL;
@Override
public String getContentList() {
//调用服务层的服务
String result = HttpClientUtil.doGet(REST_BASE_URL + REST_INDEX_AD_URL);
//把字符串转换成TaotaoResult
try {
TaotaoResult taotaoResult = TaotaoResult.formatToList(result, TbContent.class);
//取内容列表
List<TbContent> list = (List<TbContent>) taotaoResult.getData();
List<Map> resultList = new ArrayList<>();
//创建一个jsp页码要求的pojo列表
for (TbContent tbContent : list) {
Map map = new HashMap<>();
map.put("src", tbContent.getPic());
map.put("height", 240);
map.put("width", 670);
map.put("srcB", tbContent.getPic2());
map.put("widthB", 550);
map.put("heightB", 240);
map.put("href", tbContent.getUrl());
map.put("alt", tbContent.getSubTitle());
resultList.add(map);
}
return JsonUtils.objectToJson(resultList);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
}