How to install SSL certificate in java keystore

The Problem:

After adding maven repository secured with https protocol the following error appeared:

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

But how to get the certificate and make java can find it? Step 1. Fetching the certificate

echo | openssl s_client -showcerts -connect nexus:443 2>/dev/null | \
 awk '/-----BEGIN CERTIFICATE-----/, /-----END CERTIFICATE-----/' > nexus.crt

Step 2. Find out where the java keystore is located The following command will show java home dir

$ /usr/libexec/java_home
/Library/Java/JavaVirtualMachines/jdk1.8.0_101.jdk/Contents/Home

The keystore is jre/lib/security/cacerts file. Step 3. Install the certificate with keytool command

sudo keytool -importcert -alias nexus01 -keystore /Library/Java/JavaVirtualMachines/jdk1.8.0_101.jdk/Contents/Home/jre/lib/security/cacerts -file nexus.crt 

Hint: use changeit or changeme as a default password. Step 4. Verify your certificate is on the list

$ keytool -list -keystore /Library/Java/JavaVirtualMachines/jdk1.8.0_101.jdk/Contents/Home/jre/lib/security/cacerts | grep nexus01
nexus01, Nov 15, 2018, trustedCertEntry,