==================================SAMPLE CODE ==========================================
import java.net.*;
import java.io.*;

public class HttpSample {
    public static void main(String[] args) throws Exception {
        URL test = new URL("https://google.com");
        URLConnection yc = test.openConnection();
        BufferedReader in = new BufferedReader(
                                new InputStreamReader(
                                yc.getInputStream()));
        String inputLine;

        while ((inputLine = in.readLine()) != null)
            System.out.println(inputLine);
        in.close();
    }
}

==================================SAMPLE CODE ==========================================

Exception in thread "main" javax.net.ssl.SSLHandshakeException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:128)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:325)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:268)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:263)
at java.base/sun.security.ssl.CertificateMessage$T12CertificateConsumer.checkServerCerts(CertificateMessage.java:642)
at java.base/sun.security.ssl.CertificateMessage$T12CertificateConsumer.onCertificate(CertificateMessage.java:461)
at java.base/sun.security.ssl.CertificateMessage$T12CertificateConsumer.consume(CertificateMessage.java:361)
at java.base/sun.security.ssl.SSLHandshake.consume(SSLHandshake.java:390)
at java.base/sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:445)
at java.base/sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:422)
at java.base/sun.security.ssl.TransportContext.dispatch(TransportContext.java:178)
at java.base/sun.security.ssl.SSLTransport.decode(SSLTransport.java:164)
at java.base/sun.security.ssl.SSLSocketImpl.decode(SSLSocketImpl.java:877)
at java.base/sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:810)
at java.base/sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:383)
at java.base/sun.net.www.protocol.https.HttpsClient.afterConnect(HttpsClient.java:567)
at java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:185)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1581)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1509)
at java.base/sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:245)
at HttpSample.main(HttpSample.java:10)
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 java.base/sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:385)
at java.base/sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:290)
at java.base/sun.security.validator.Validator.validate(Validator.java:264)
at java.base/sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:321)
at java.base/sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:221)
at java.base/sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:129)
at java.base/sun.security.ssl.CertificateMessage$T12CertificateConsumer.checkServerCerts(CertificateMessage.java:626)
... 16 more
Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at java.base/sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:141)
at java.base/sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:126)
at java.base/java.security.cert.CertPathBuilder.build(CertPathBuilder.java:297)
at java.base/sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:380)
... 22 more