httpClient4.5（一）
阿新 • • 發佈：2018-12-14
我們經常會遇到與第三方系統之間進行網路互動，此時通常會使用httpClient來訪問第三方系統提供的介面進行相應的互動。
一、httpClient簡介： HttpClient 是 Apache Jakarta Common 下的子專案，可以用來提供高效的、最新的、功能豐富的支援 HTTP 協議的客戶端程式設計工具包，並且它支援 HTTP 協議最新的版本和建議。
使用HttpClient傳送請求、接收響應很簡單，一般需要如下幾步即可： 1.建立CloseableHttpClient物件。 2.建立請求方法的例項，並指定請求URL。如果需要傳送GET請求，建立HttpGet物件；如果需要傳送POST請求，建立HttpPost物件。 3.如果需要傳送請求引數，可呼叫setEntity(HttpEntity entity)方法來設定請求引數。 4.呼叫HttpGet、HttpPost物件的setHeader(String name, String value)方法設定header資訊，或者呼叫setHeaders(Header[] headers)設定一組header資訊。 5.呼叫CloseableHttpClient物件的execute(HttpUriRequest request)傳送請求，該方法返回一個CloseableHttpResponse。 6.呼叫HttpResponse的getEntity()方法可獲取HttpEntity物件，該物件包裝了伺服器的響應內容。程式可通過該物件獲取伺服器的響應內容；呼叫CloseableHttpResponse的getAllHeaders()、getHeaders(String name)等方法可獲取伺服器的響應頭。 7.釋放連線。無論執行方法是否成功，都必須釋放連線
二、httpClient程式設計：
1、pom.xml：
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.http.demo</groupId> <artifactId>http</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>http</name> <url>http://maven.apache.org</url> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <httpcore.version>4.4.6</httpcore.version> <httpclient.version>4.5.5</httpclient.version> <slf4j.version>1.7.25</slf4j.version> <fastjson.version>1.2.47</fastjson.version> </properties> <dependencies> <!-- http client --> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> <version>${httpclient.version}</version> </dependency> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpcore</artifactId> <version>${httpcore.version}</version> </dependency> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpmime</artifactId> <version>${httpclient.version}</version> </dependency> <!-- slf4j --> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> <version>${slf4j.version}</version> </dependency> <!-- fastjson --> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>${fastjson.version}</version> </dependency> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-lang3</artifactId> <version>3.1</version> </dependency> </dependencies> <!-- jdk1.7 --> <build> <finalName>${project.artifactId}-${project.version}</finalName> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.1</version> <configuration> <source>1.7</source> <target>1.7</target> </configuration> </plugin> </plugins> </build> </project>
- 簡單的httpClient例項
/** - 簡單httpclient例項 - @version 1.0 */ public class SimpleHttpClientDemo { /** * 模擬請求 * * @param url 資源地址 * @param map 引數列表 * @param encoding 編碼 * @return * @throws ParseException * @throws IOException */ public static String send(String url, Map<String,String> map,String encoding) throws ParseException, IOException{ String body = ""; //建立httpclient物件 CloseableHttpClient client = HttpClients.createDefault(); //建立post方式請求物件 HttpPost httpPost = new HttpPost(url); //裝填引數 List<NameValuePair> nvps = new ArrayList<NameValuePair>(); if(map!=null){ for (Entry<String, String> entry : map.entrySet()) { nvps.add(new BasicNameValuePair(entry.getKey(), entry.getValue())); } } //設定引數到請求物件中 httpPost.setEntity(new UrlEncodedFormEntity(nvps, encoding)); System.out.println("請求地址："+url); System.out.println("請求引數："+nvps.toString()); //設定header資訊 //指定報文頭【Content-type】、【User-Agent】 httpPost.setHeader("Content-type", "application/x-www-form-urlencoded"); httpPost.setHeader("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)"); //執行請求操作，並拿到結果（同步阻塞） CloseableHttpResponse response = client.execute(httpPost); //獲取結果實體 HttpEntity entity = response.getEntity(); if (entity != null) { //按指定編碼轉換結果實體為String型別 body = EntityUtils.toString(entity, encoding); } EntityUtils.consume(entity); //釋放連結 response.close(); return body; } }
- 對於HTTPS的訪問，採取繞過證書的策略：
/**
* 繞過驗證
*
* @return
* @throws NoSuchAlgorithmException
* @throws KeyManagementException
*/
public static SSLContext createIgnoreVerifySSL() throws NoSuchAlgorithmException, KeyManagementException {
SSLContext sc = SSLContext.getInstance("SSLv3");
// 實現一個X509TrustManager介面，用於繞過驗證，不用修改裡面的方法
X509TrustManager trustManager = new X509TrustManager() {
@Override
public void checkClientTrusted(
java.security.cert.X509Certificate[] paramArrayOfX509Certificate,
String paramString) throws CertificateException {
}
@Override
public void checkServerTrusted(
java.security.cert.X509Certificate[] paramArrayOfX509Certificate,
String paramString) throws CertificateException {
}
@Override
public java.security.cert.X509Certificate[] getAcceptedIssuers() {
return null;
}
};
sc.init(null, new TrustManager[] { trustManager }, null);
return sc;
}
然後修改原來的send方法：
/**
* 模擬請求
*
* @param url 資源地址
* @param map 引數列表
* @param encoding 編碼
* @return
* @throws NoSuchAlgorithmException
* @throws KeyManagementException
* @throws IOException
* @throws ClientProtocolException
*/
public static String send(String url, Map<String,String> map,String encoding) throws KeyManagementException, NoSuchAlgorithmException, ClientProtocolException, IOException {
String body = "";
//採用繞過驗證的方式處理https請求
SSLContext sslcontext = createIgnoreVerifySSL();
// 設定協議http和https對應的處理socket連結工廠的物件
Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory>create()
.register("http", PlainConnectionSocketFactory.INSTANCE)
.register("https", new SSLConnectionSocketFactory(sslcontext))
.build();
PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager(socketFactoryRegistry);
HttpClients.custom().setConnectionManager(connManager);
//建立自定義的httpclient物件
CloseableHttpClient client = HttpClients.custom().setConnectionManager(connManager).build();
// CloseableHttpClient client = HttpClients.createDefault();
//建立post方式請求物件
HttpPost httpPost = new HttpPost(url);
//裝填引數
List<NameValuePair> nvps = new ArrayList<NameValuePair>();
if(map!=null){
for (Entry<String, String> entry : map.entrySet()) {
nvps.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
}
}
//設定引數到請求物件中
httpPost.setEntity(new UrlEncodedFormEntity(nvps, encoding));
System.out.println("請求地址："+url);
System.out.println("請求引數："+nvps.toString());
//設定header資訊
//指定報文頭【Content-type】、【User-Agent】
httpPost.setHeader("Content-type", "application/x-www-form-urlencoded");
httpPost.setHeader("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)");
//執行請求操作，並拿到結果（同步阻塞）
CloseableHttpResponse response = client.execute(httpPost);
//獲取結果實體
HttpEntity entity = response.getEntity();
if (entity != null) {
//按指定編碼轉換結果實體為String型別
body = EntityUtils.toString(entity, encoding);
}
EntityUtils.consume(entity);
//釋放連結
response.close();
return body;
}
但是，如果是自己用jdk或者其他工具生成的證書，還是希望用其他方式認證自簽名的證書，這篇文章就來分享一下如何設定信任自簽名的證書。當然你也可以參考官網示例中。
- 要想信任自簽名的證書，必須得知道金鑰庫的路徑及金鑰庫的密碼。然後載入到程式來才可以。
/**
* 設定信任自簽名證書
*
* @param keyStorePath 金鑰庫路徑
* @param keyStorepass 金鑰庫密碼
* @return
*/
public static SSLContext custom(String keyStorePath, String keyStorepass){
SSLContext sc = null;
FileInputStream instream = null;
KeyStore trustStore = null;
try {
trustStore = KeyStore.getInstance(KeyStore.getDefaultType());
instream = new FileInputStream(new File(keyStorePath));
trustStore.load(instream, keyStorepass.toCharArray());
// 相信自己的CA和所有自簽名的證書
sc = SSLContexts.custom().loadTrustMaterial(trustStore, new TrustSelfSignedStrategy()).build();
} catch (KeyStoreException | NoSuchAlgorithmException| CertificateException | IOException | KeyManagementException e) {
e.printStackTrace();
} finally {
try {
instream.close();
} catch (IOException e) {
}
}
return sc;
}
然後修改原來的send方法：
/**
* 模擬請求
*
* @param url 資源地址
* @param map 引數列表
* @param encoding 編碼
* @return
* @throws ParseException
* @throws IOException
* @throws KeyManagementException
* @throws NoSuchAlgorithmException
* @throws ClientProtocolException
*/
public static String send(String url, Map<String,String> map,String encoding) throws ClientProtocolException, IOException {
String body = "";
//tomcat是我自己的金鑰庫的密碼，你可以替換成自己的
//如果密碼為空，則用"nopassword"代替
SSLContext sslcontext = custom("D:\\keys\\wsriakey", "tomcat");
// 設定協議http和https對應的處理socket連結工廠的物件
Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory>create()
.register("http", PlainConnectionSocketFactory.INSTANCE)
.register("https", new SSLConnectionSocketFactory(sslcontext))
.build();
PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager(socketFactoryRegistry);
HttpClients.custom().setConnectionManager(connManager);
//建立自定義的httpclient物件
CloseableHttpClient client = HttpClients.custom().setConnectionManager(connManager).build();
// CloseableHttpClient client = HttpClients.createDefault();
//建立post方式請求物件
HttpPost httpPost = new HttpPost(url);
//裝填引數
List<NameValuePair> nvps = new ArrayList<NameValuePair>();
if(map!=null){
for (Entry<String, String> entry : map.entrySet()) {
nvps.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
}
}
//設定引數到請求物件中
httpPost.setEntity(new UrlEncodedFormEntity(nvps, encoding));
System.out.println("請求地址："+url);
System.out.println("請求引數："+nvps.toString());
//設定header資訊
//指定報文頭【Content-type】、【User-Agent】
httpPost.setHeader("Content-type", "application/x-www-form-urlencoded");
httpPost.setHeader("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)");
//執行請求操作，並拿到結果（同步阻塞）
CloseableHttpResponse response = client.execute(httpPost);
//獲取結果實體
HttpEntity entity = response.getEntity();
if (entity != null) {
//按指定編碼轉換結果實體為String型別
body = EntityUtils.toString(entity, encoding);
}
EntityUtils.consume(entity);
//釋放連結
response.close();
return body;
}