[网络协议]kkfileview:预览自签https word文件 出现unable to find valid certification path to requested target

使用kkfileview预览自签https word文件时，出现ssl证书错误
javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at sun.security.ssl.Alerts.getSSLException(Alerts.java:192)
at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1884)
at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:276)
at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:270)
at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1341)
at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:153)
at sun.security.ssl.Handshaker.processLoop(Handshaker.java:868)
at sun.security.ssl.Handshaker.process_record(Handshaker.java:804)
at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1016)
at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1312)
at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1339)
at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1323)
at sun.net.www.protocol.https.HttpsClient.afterConnect(HttpsClient.java:563)
at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:185)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1300)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:254)
at SslTest.getRequest(SslTest.java:16)
at SslTest.main(SslTest.java:40)
Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:385)
at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:230)
at sun.security.validator.Validator.validate(Validator.java:260)
在源码中添加SslUtils类

package cn.keking.utils;


import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import javax.net.ssl.*;
/**
 * @author Fbin
 * @date 2022/6/23
 * @Description
 * @annotation 高山仰止, 景行行止.虽不能至, 心向往之
 */
public class SslUtils {
    /**
     * 忽略HTTPS请求的SSL证书，必须在openConnection之前调用
     * @throws Exception
     */
    public static void ignoreSsl() throws Exception{
        HostnameVerifier hv = new HostnameVerifier() {
            @Override
            public boolean verify(String urlHostName, SSLSession session) {
                System.out.println("Warning: URL Host: " + urlHostName + " vs. " + session.getPeerHost());
                return true;
            }
        };
        trustAllHttpsCertificates();
        HttpsURLConnection.setDefaultHostnameVerifier(hv);
    }

    private static void trustAllHttpsCertificates() throws Exception {
        TrustManager[] trustAllCerts = new TrustManager[1];
        TrustManager tm = new miTM();
        trustAllCerts[0] = tm;
        SSLContext sc = SSLContext.getInstance("SSL");
        sc.init(null, trustAllCerts, null);
        HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
    }

    static class miTM implements TrustManager,X509TrustManager {
        @Override
        public X509Certificate[] getAcceptedIssuers() {
            return null;
        }
        public boolean isServerTrusted(X509Certificate[] certs) {
            return true;
        }
        public boolean isClientTrusted(X509Certificate[] certs) {
            return true;
        }
        @Override
        public void checkServerTrusted(X509Certificate[] certs, String authType)
                throws CertificateException {
            return;
        }
        @Override
        public void checkClientTrusted(X509Certificate[] certs, String authType)
                throws CertificateException {
            return;
        }
    }
}

同时在下载文件DownloadUtils.download 方法里面增加

//忽略SSL认证
SslUtils.ignoreSsl();

如下

 public static ReturnResponse<String> downLoad(FileAttribute fileAttribute, String fileName) {
        String urlStr = fileAttribute.getUrl();
        ReturnResponse<String> response = new ReturnResponse<>(0, "下载成功!!!", "");
        String realPath = DownloadUtils.getRelFilePath(fileName, fileAttribute);
        try {
            URL url = WebUtils.normalizedURL(urlStr);
            if (isHttpUrl(url)) {
                //忽略SSL认证
                SslUtils.ignoreSsl();
                File realFile = new File(realPath);
                FileUtils.copyURLToFile(url, realFile);
            } else if (isFtpUrl(url)) {
                String ftpUsername = WebUtils.getUrlParameterReg(fileAttribute.getUrl(), URL_PARAM_FTP_USERNAME);
                String ftpPassword = WebUtils.getUrlParameterReg(fileAttribute.getUrl(), URL_PARAM_FTP_PASSWORD);
                String ftpControlEncoding = WebUtils.getUrlParameterReg(fileAttribute.getUrl(), URL_PARAM_FTP_CONTROL_ENCODING);
                FtpUtils.download(fileAttribute.getUrl(), realPath, ftpUsername, ftpPassword, ftpControlEncoding);
            } else {
                response.setCode(1);
                response.setMsg("url不能识别url" + urlStr);
            }
            response.setContent(realPath);
            response.setMsg(fileName);
            return response;
        } catch (Exception e) {
            logger.error("文件下载失败，url：{}", urlStr, e);
            response.setCode(1);
            response.setContent(null);
            if (e instanceof FileNotFoundException) {
                response.setMsg("文件不存在!!!");
            } else {
                response.setMsg(e.getMessage());
            }
            return response;
        }
    }