#!/bin/bash

#
# Script to check the number of connections in a JBoss connection pool via JMX and
# invoke flush() if the connection count is over a certain limit
#

JBOSS_HOME=/apps/jboss-eap-4.3/jboss-as
JBOSS_USER=admin
JBOSS_PASSWORD=secret1
JDBC_POOL_MBEAN="jboss.jca:service=ManagedConnectionPool,name=example_ds"
JBOSS_URL=fenris.khill.org:1099
JBOSS_INSTANCE_NAME=development

MAX_CONN_COUNT=100

CONN_COUNT=`$JBOSS_HOME/bin/twiddle.sh --server=$JBOSS_URL -u $JBOSS_USER -p $JBOSS_PASSWORD get $JDBC_POOL_MBEAN InUseConnectionCount | cut -d "=" -f 2`

if [ $CONN_COUNT -ge $MAX_CONN_COUNT ]; then
    echo "Connection pool has exceeded maximum size!"
    # invoke a thread dump
    kill -3 `ps auxw | grep java | grep $JBOSS_INSTANCE_NAME | grep -v grep | awk '{print $2}'`
    # wait a bit and take another dump
    echo "Sleeping for 10 seconds before second thread dump..."
    sleep 10
    kill -3 `ps auxw | grep java | grep $JBOSS_INSTANCE_NAME | grep -v grep | awk '{print $2}'`
    echo "Thread dumps completed.  Flushing JDBC connection pool..."
    # flush the JDBC Pool
    $JBOSS_HOME/bin/twiddle.sh --server=$JBOSS_URL -u $JBOSS_USER -p $JBOSS_PASSWORD invoke $JDBC_POOL_MBEAN flush
    echo "Recovery complete"
else
    echo "Connection count $CONN_COUNT is within acceptable limits"
fi