How to ensure server certificate is created with which private key through java

Customer has created key and certificate using openssl command below

openssl req -newkey rsa:1024 -sha1 -keyout OCkey.pem -out OCreq.pem -subj "/C=country/L=city/O=OCserver/OU=myLab/CN=OCserverName/" -config req.conf

openssl ca -in OCreq.pem -cert CAcert.pem -keyfile CAkey.pem -out OCcert.pem -days 3650 -config sign.conf -extfile sign.ext -md sha1 -notext

So they have given me the certificate(OCcert.pem) and private key (OCkey.pem).

How to ensure that OCcert.pem is created through OCkey.pem using Java?

Note :I can't ask customer开发者_Go百科 to change the ssl command.

Please help.

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they have given me the certificate(OCcert.pem) and private key (OCkey.pem)

Why? They should throw that private key away immediately, it is compromised. What was the purpose of this exercise?