You can change the password for a given private/secret key in a keystore
by using keytool with the following options
keypasswd {-alias alias} [-keypass old_keypass] [-new new_keypass]
{-storetype storetype} {-keystore keystore} [-storepass storepass]
{-providerName provider_name} {-providerClass provider_class_name
{-providerArg provider_arg}} {-v} {-Jjavaoption}