HTTP-java訪問https資源時,忽略證書信任問題，代碼栗子

java程序在訪問https資源時，出現報錯

sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

這本質上，是java在訪問https資源時的證書信任問題。如何解決這個問題呢？

關於這個問題有一篇博客做了很詳細的解釋，需要理解的可以查看： http://blog.csdn.net/lizeyang/article/details/18983843

 

以下是結合我具體情況的一個小栗子：

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.SSLSession;

import org.apache.log4j.Logger;
import org.htmlparser.util.ParserException;

import com.xwtech.parser.GetRequestHtmlParser;
import com.xwtech.pojo.ExtendCandidate;
/*
 * GET請求類
 */
public class GetRequest {
    private String url = "https://b2b.10086.cn/b2b/main/viewNoticeContent.html?noticeBean.id=";
    private Logger logger;
    public GetRequest() {
        logger = Logger.getLogger(GetRequest.class);
    }
    private static void trustAllHttpsCertificates() throws Exception {
        javax.net.ssl.TrustManager[] trustAllCerts = new javax.net.ssl.TrustManager[1];
        javax.net.ssl.TrustManager tm = new miTM();
        trustAllCerts[0] = tm;
        javax.net.ssl.SSLContext sc = javax.net.ssl.SSLContext.getInstance("SSL");
        sc.init(null, trustAllCerts, null);
        javax.net.ssl.HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
    }
    //為更好的演示，去掉了不相關的代碼
    public void getData(String id) {
        this.url = url + id;
        BufferedReader in = null;
        HttpURLConnection conn = null;
        String result = "";
        try {
　　　　　　　　//該部分必須在獲取connection前調用
            trustAllHttpsCertificates(); HostnameVerifier hv = new HostnameVerifier() {
                public boolean verify(String urlHostName, SSLSession session) {
                    logger.info("Warning: URL Host: " + urlHostName + " vs. " + session.getPeerHost());
                    return true; } };
            HttpsURLConnection.setDefaultHostnameVerifier(hv);
            conn = (HttpURLConnection)new URL(url).openConnection();
            // 發送GET請求必須設置如下兩行
            conn.setDoInput(true);
            conn.setRequestMethod("GET");
            // flush輸出流的緩沖
            in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            logger.error("發送 GET 請求出現異常！\t請求ID:"+id+"\n"+e.getMessage()+"\n");
        } finally {// 使用finally塊來關閉輸出流、輸入流
            try {
                if (in != null) {
                    in.close();
                }
            } catch (IOException ex) {
                logger.error("關閉數據流出錯了！\n"+ex.getMessage()+"\n");
            }
        }
        // 獲得相應結果result,可以直接處理......
        
    }
    static class miTM implements javax.net.ssl.TrustManager, javax.net.ssl.X509TrustManager {
        public java.security.cert.X509Certificate[] getAcceptedIssuers() {
            return null;
        }

        public boolean isServerTrusted(java.security.cert.X509Certificate[] certs) {
            return true;
        }

        public boolean isClientTrusted(java.security.cert.X509Certificate[] certs) {
            return true;
        }

        public void checkServerTrusted(java.security.cert.X509Certificate[] certs, String authType)
                throws java.security.cert.CertificateException {
            return;
        }

        public void checkClientTrusted(java.security.cert.X509Certificate[] certs, String authType)
                throws java.security.cert.CertificateException {
            return; } }
}

與正常get請求相比，多了紅色的部分，不忽略證書信任的代碼可以參考我另外一篇博客：

　　http://www.cnblogs.com/husky/p/6377577.html

就是在進行連接前需要顯示調用以下進行忽略證書信任：

trustAllHttpsCertificates();　　　　// 這是一個方法，具體見上面
HttpsURLConnection.setDefaultHostnameVerifier(hv);　　　　　　　　//這里HttpsURLConnection是類名,hv參數需要自己創建，具體可以參考上面。

Post請求需要忽略證書信任與這個一樣，在獲取連接前，加上以上代碼。

相關文章：

　　java實現Get請求： http://www.cnblogs.com/husky/p/6377577.html

　　java實現Post請求： http://www.cnblogs.com/husky/p/6377553.html