接口调用异常：javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find vali

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.Alert.createSSLException(Alert.java:131)
	at sun.security.ssl.TransportContext.fatal(TransportContext.java:353)
	at sun.security.ssl.TransportContext.fatal(TransportContext.java:296)
	at sun.security.ssl.TransportContext.fatal(TransportContext.java:291)
	at sun.security.ssl.CertificateMessage$T12CertificateConsumer.checkServerCerts(CertificateMessage.java:652)
	at sun.security.ssl.CertificateMessage$T12CertificateConsumer.onCertificate(CertificateMessage.java:471)
	at sun.security.ssl.CertificateMessage$T12CertificateConsumer.consume(CertificateMessage.java:367)
	at sun.security.ssl.SSLHandshake.consume(SSLHandshake.java:376)
	at sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:444)
	at sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:422)
	at sun.security.ssl.TransportContext.dispatch(TransportContext.java:183)
	at sun.security.ssl.SSLTransport.decode(SSLTransport.java:154)
	at sun.security.ssl.SSLSocketImpl.decode(SSLSocketImpl.java:1279)
	at sun.security.ssl.SSLSocketImpl.readHandshakeRecord(SSLSocketImpl.java:1188)
	at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:401)
	at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:373)

异常原因：由于JVM默认信任证书不包含该目标网站的SSL证书，导致无法建立有效的信任链接。

解决方法改为不校验，直接全部信任（安全性不高情况下）。代码如下

URL console = new URL(url);
HttpURLConnection conn = (HttpURLConnection) console.openConnection();
if (conn instanceof HttpsURLConnection)  {
    SSLContext sc = SSLContext.getInstance("SSL");
    sc.init(null, new TrustManager[]{new TrustAnyTrustManager()}, new java.security.SecureRandom());
    ((HttpsURLConnection) conn).setSSLSocketFactory(sc.getSocketFactory());
    ((HttpsURLConnection) conn).setHostnameVerifier(new TrustAnyHostnameVerifier());
}
conn.connect();
InputStream inputStream = conn.getInputStream();
PdfReader pdfReader = new PdfReader(inputStream);
inputStream.close();
conn.disconnect();