replace the value with ${<your variable name>:<your default>}
e.g. minPoolsize ==> <min-pool-size>${my.min.pool.size:5}</min-pool-size>
in that case you can add -Dmy.min.pool.size=10 to the JVM start (e.g. to run.conf JAVA_OPTS) or start run.sh -Dmy.min.pool.size=10