Everthing on Java.
Environment: RedHat Linux 12.3
NOTE: 1. Old model: There was NO A.java
"script.sh" starts/stops B.java as process
2. New model: There IS A.java
"script.sh" never uses A
"script.sh" starts B.java as process.
"myGraceful.sh" stops process Gracefully
"script.sh" is NEVER used for stopping
Server(B.java in server.jar):
Java Process triggered as: ./script.sh {start|stop}
Its a legacy class existing for 10 yrs or more
has RemoteB Interface
has
graceFul(){ ..handles all DB ,user states,connection...etc ..works perfectly from Admin ..invoked as RMI from JSP ..never invoked by script till now } initServer(){...} getUsers(){...}
Requirement & My Effort:
Everyone knows how the code RMI Looks or .sh to invoke java. Hence I dont think pasting a proprietary code should be expected here.
Graceful needs to be done from shell script on same Server node. On Server everything runniing by Spring. I will die if I try to Inject a Bean as there is going to be 100x1000 dependencies coming in queue. Hence I created
RMI Client(com/common/task/A.java in same server.jar):
- A can be triggered by: ./myGraceful.sh stop (eg. java -cp... com.A 2>&1)
- in same server.jar - hence inevitaby loaded (note not running) on same Server node.
- having p s v main(String args[])
- Forks Thread ..thread calls RMI shutdown on B ...and thread expected to die on own.
Problem:
Server shutting down perfectly. Then If I isssue following command AGAIN and AGAIN:
./script.sh start
Server starts up. But within a minute it stops automatically. I dont have any clue what and which is stopping the Server. I Observed
Prior to any of my new modifications:
"./script.sh stop" [used to work flawlessly calling kill -9 $pid ]
"ps - aefwww | grep java" used to show:
pid ppid.. /usr/java/jdk/bin/java ........java -D.... -Djava.timeout=.. -D....
pid ppid.. .../abc/ ....java...
pid ppid.. .../xyz/ .................java...
But now
"./myGraceful.sh stop" triggers modified server.jar(which now has A.java):
"ps - aefwww | grep java" shows:
pid ppid.. .../abc/ ....java...
pid ppid.. .../xyz/ .................java...
Here goes some code:
myGraceful.sh:
----------------
#!/bin/bash
CLASSPATH=$COMMON_CLASS_PATH:$LIB_INHOUSE/server.jar
rmiIp=x.y.zz.www [hidden]
rmiPort=xxxx [hidden]
peerId=1
period=5
function kill_server(){
echo -n "Shutting down Server ($pid): "
echo "executing Arnab"
echo "arg0 : $0 pid : $pid"
java -Djava.rmi.server.hostname=localhost \
com.common.task.GracefulRunner $rmiIp $rmiPort $peerId $period 2>&1
echo Done
}
case "$1" in
start)
get_pids "CustomBootstrap" $2
if [ "$pid" != "" ] ; then
get_processname "CustomBootstrap" $2
if [ "$server" != "" ] ; then
echo "Server already running. pid = $pid"
exit 1
fi
if [ "$ctserver" != "" ] ; then
echo "Shutting down CT Server($pid): "
kill -SIGQUIT $pid
kill -9 $pid
echo Done
fi
fi
$0 run $2 1>&2 &
sleep 2
$0 status $2
# $0 err
;;
stop)
$0 kill $2
;;
kill)
get_pids "CustomBootstrap" $2
if [ "$pid" != "" ] ; then
kill_server
echo "Server ended at `date`"
else
get_pids "Launcher" $2
if [ "$pid" != "" ] ; then
kill_server
else
echo "Server is not running !"
fi
fi
;;
esac
A.java
public class A {
class GracefulStopperThread implements Runnable{
private String serverRMIIp = null;
private int serverRmiPort =0;
private String serverPeerId =null;
private int shutDownPeriod =0;
public GracefulStopperThread(String rmiIp,String rmiPort,String peerId,String period){
serverRMIIp = rmiIp;
serverRmiPort = Integer.parseInt(rmiPort);
serverPeerId = peerId;
shutDownPeriod =Integer.parseInt(period);
}
public void run() {
System.out.println("***************************************** GracefulStopper is running *******************************************");
System.out.println("serverPeerId :="+serverPeerId+" , shutDownPeriod :="+shutDownPeriod);
try {
IRemoteServer serverRef = null;
String rmiUrl = getURL(serverRMIIp,serverRmiPort,serverPeerId);
System.out.println("THE RMI URL : "+rmiUrl);
serverRef = (IRemoteServer) Naming.lookup(rmiUrl );
com.server.ds.IRemoteServer pcServerRef = (com.server.ds.IRemoteServer) serverRef;
pcServerRef.graceful(SHUTDOWN_TYPE_SERVER_NOTSYSTEM,"Gracefully Shutting down withing 10 mins", shutDownPeriod);
System.out.println("GracefulStopperThread completed ");
} catch (Exception e) {
e.printStackTrace();
}
}
private String getURL(String rmiIp,int rmiPort,String peerId) {
return new StringBuffer(32).append("rmi://").append(serverRMIIp).append(':').append(serverRmiPort)
.append('/').append(serverPeerId).toString();
}
}
public static void main(String args[]) throws InterruptedException {
A agent = new A();
Runnable stopper = agent.new GracefulStopperThread(args[0],args[1],args[2],args[3]);
Thread t = new Thread(stopper);
t.start();
t.join();
System.out.println("MainThread completed ");
}
}
