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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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package org.jgroups.protocols;

import org.jgroups.annotations.Property;
import org.jgroups.annotations.Unsupported;
import org.jgroups.logging.Log;
import org.jgroups.stack.IpAddress;
import org.jgroups.util.Util;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.Date;

/**
 * Protocol which uses an executable (e.g. /sbin/ping, or a script) to check whether a given host is up or not,
 * taking 1 argument; the host name of the host to be pinged. Property 'cmd' determines the program to be executed
 * (use a fully qualified name if the program is not on the path).
 * @author Bela Ban
 * @deprecated Use {@link org.jgroups.protocols.FD_HOST} instead. Will be removed in 4.0.
 */
@Unsupported
@Deprecated
public class FD_PING extends FD {
    /** Command (script or executable) to ping a host: a return value of 0 means success, anything else is a failure.
     * The only argument passed to cmd is the host's address (symbolic name or dotted-decimal IP address) */
    @Property(description="Command (script or executable) to ping a host: a return value of 0 means success, anything else is a failure. Default is ping")
    String cmd="ping";
  
    @Property(description="Write the stdout of the command to the log. Default is true")
    boolean verbose=true;

    protected Monitor createMonitor() {
        return new PingMonitor();
    }


    /**
     * Executes the ping command. Each time the command fails, we increment num_tries. If num_tries > max_tries, we
     * emit a SUSPECT message. If ping_dest changes, or we do receive traffic from ping_dest, we reset num_tries to 0.
     */
    protected class PingMonitor extends Monitor {

        public void run() {
            if(ping_dest == null) {
                if(log.isWarnEnabled())
                    log.warn("ping_dest is null: members=" + members + ", pingable_mbrs=" +
                            pingable_mbrs + ", local_addr=" + local_addr);
                return;
            }


            // 1. execute ping command
            String host=ping_dest instanceof IpAddress? ((IpAddress)ping_dest).getIpAddress().getHostAddress() : ping_dest.toString();
            String command=cmd + " " + host;
            if(log.isDebugEnabled())
                log.debug("executing \"" + command + "\" (own address=" + local_addr + ')');
            try {
                Log tmp_log=verbose? log : null;
                int rc=Pinger.execute(command, tmp_log);
                num_heartbeats++;
                if(rc == 0) { // success
                    num_tries.set(0);
                }
                else { // failure
                    num_tries.incrementAndGet();
                    if(log.isDebugEnabled())
                        log.debug("could not ping " + ping_dest + " (tries=" + num_tries + ')');
                }

                int tmp_tries=num_tries.get();
                if(tmp_tries >= max_tries) {
                    if(log.isDebugEnabled())
                        log.debug("[" + local_addr + "]: could not ping " + ping_dest + " for " + (tmp_tries +1) +
                                " times (" + ((tmp_tries+1) * timeout) + " milliseconds), suspecting it");
                    // broadcast a SUSPECT message to all members - loop until
                    // unsuspect or view change is received
                    bcast_task.addSuspectedMember(ping_dest);
                    num_tries.set(0);
                    if(stats) {
                        num_suspect_events++;
                        suspect_history.add(String.format("%s: %s", new Date(), ping_dest));
                    }
                }
            }
            catch(Exception ex) {
                if(log.isErrorEnabled())
                    log.error("failed executing command " + command, ex);
            }
        }
    }



    protected static class Pinger {

        static int execute(String command, Log log) throws IOException, InterruptedException {
            Process p=Runtime.getRuntime().exec(command);
            InputStream in=p.getInputStream(), err=p.getErrorStream();
            try {
                Reader in_reader, err_reader;
                in_reader=new Reader(in, log);
                err_reader=new Reader(err, log);
                in_reader.start();
                err_reader.start();
                in_reader.join();
                err_reader.join();
                return p.exitValue();
            }
            finally {
                Util.close(in);
                Util.close(err);
            }
        }


        static class Reader extends Thread {
            InputStreamReader in;
            Log               log=null;
            boolean           trace=false;

            Reader(InputStream in, Log log) {
                this.in=new InputStreamReader(in);
                this.log=log;
                if(log != null) {
                    trace=log.isTraceEnabled();
                }
            }

            public void run() {
                int c;
                StringBuilder sb=new StringBuilder();
                while(true) {
                    try {
                        c=in.read();
                        if(c == -1)
                            break;
                        sb.append((char)c);
                    }
                    catch(IOException e) {
                        break;
                    }
                }
                if(log.isTraceEnabled())
                    log.trace(sb.toString());
            }
        }
    }

}