After the package installation is complete, the next step is to
make sure that the system can properly find the files. If you set
up your login scripts as recommended in The
Bash Shell Startup Files, update the environment by creating
the openjdk.sh
script, as the
root
user:
cat > /etc/profile.d/openjdk.sh << "EOF"
# Begin /etc/profile.d/openjdk.sh
# Set JAVA_HOME directory
JAVA_HOME=/opt/jdk
# Adjust PATH
pathappend $JAVA_HOME/bin
# Auto Java CLASSPATH: Copy jar files to, or create symlinks in, the
# /usr/share/java directory.
AUTO_CLASSPATH_DIR=/usr/share/java
pathprepend . CLASSPATH
for dir in `find ${AUTO_CLASSPATH_DIR} -type d 2>/dev/null`; do
pathappend $dir CLASSPATH
done
for jar in `find ${AUTO_CLASSPATH_DIR} -name "*.jar" 2>/dev/null`; do
pathappend $jar CLASSPATH
done
export JAVA_HOME
# By default, Java creates several files in a directory named
# /tmp/hsperfdata_[username]. This directory contains files that are used for
# performance monitoring and profiling, but aren't normally needed on a BLFS
# system. This environment variable disables that feature.
_JAVA_OPTIONS="-XX:-UsePerfData"
export _JAVA_OPTIONS
unset AUTO_CLASSPATH_DIR dir jar _JAVA_OPTIONS
# End /etc/profile.d/openjdk.sh
EOF
If Sudo-1.9.16 is installed, the super user should
have access to the above variables. Execute the following commands
as the root
user:
cat > /etc/sudoers.d/java << "EOF"
Defaults env_keep += JAVA_HOME
Defaults env_keep += CLASSPATH
Defaults env_keep += _JAVA_OPTIONS
EOF
To use mandb to
include the OpenJDK man pages in its database, issue, as the
root
user:
cat >> /etc/man_db.conf << "EOF" &&
# Begin Java addition
MANDATORY_MANPATH /opt/jdk/man
MANPATH_MAP /opt/jdk/bin /opt/jdk/man
MANDB_MAP /opt/jdk/man /var/cache/man/jdk
# End Java addition
EOF
mkdir -p /var/cache/man &&
mandb -c /opt/jdk/man
OpenJDK uses its own format for
the CA certificates. The Java security modules use $JAVA_HOME
/lib/security/cacerts
by default. In order to
keep all the certificates in one place, we use /etc/ssl/java/cacerts
. The instructions on the
make-ca-1.14 page previously created the file
located in /etc/ssl/java
. Set up a
symlink in the default location as the root
user:
ln -sfv /etc/pki/tls/java/cacerts /opt/jdk/lib/security/cacerts
Use the following command to check if the cacerts
file has been successfully installed:
/opt/jdk/bin/keytool -list -cacerts
At the prompt Enter keystore
password:
, enter changeit
(the default) or just
press the “Enter” key. If the cacerts
file was installed correctly, you will
see a list of the certificates with related information for each
one. If not, you need to reinstall them.
If you later install a new JVM, you just have to create the symlink in the default location to be able to use the cacerts.