Есть в idea.sh такие строки:
if [ $OPEN_JDK -eq 0 ]; then
echo "WARNING: You are launching the IDE using OpenJDK Java runtime."
echo
echo " ITS KNOWN TO HAVE PERFORMANCE AND GRAPHICS ISSUES!"
echo " SWITCH TO THE ORACLE(SUN) JDK BEFORE REPORTING PROBLEMS!"
echo
echo "NOTE: If you have both Oracle (Sun) JDK and OpenJDK installed"
echo " please validate either IDEA_JDK, JDK_HOME, or JAVA_HOME environment variable points to valid Oracle (Sun) JDK installation."
echo " See http://ow.ly/6TuKQ for more info on switching default JDK."
echo
echo "Press Enter to continue."
# ---------------------------------------------------------------------
# COMMENT LINE BELOW TO REMOVE PAUSE AFTER OPEN JDK WARNING
# ---------------------------------------------------------------------
read IGNORE
fi
