org.jgroups.util.ResponseCollector Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of infinispan-embedded
Infinispan Embedded All-in-One module
There is a newer version: 9.1.7.Final
package org.jgroups.util;

import org.jgroups.Address;
import org.jgroups.annotations.GuardedBy;

import java.util.*;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/** Similar to AckCollector, but collects responses from cluster members, not just acks. Null is not a valid key.
 * @author Bela Ban
 */
public class ResponseCollector implements org.jgroups.util.Condition {
    @GuardedBy("lock")
    private final Map responses;
    private final Lock           lock=new ReentrantLock(false);
    private final CondVar        cond=new CondVar(lock);


    /**
     *
     * @param members List of members from which we expect responses
     */
    public ResponseCollector(Collection members) {
        responses=members != null? new HashMap(members.size()) : new HashMap();
        reset(members);
    }

    public ResponseCollector(Address ... members) {
        responses=members != null? new HashMap(members.length) : new HashMap();
        reset(members);
    }

    public ResponseCollector() {
        responses=new HashMap();
    }

    public void add(Address member, T data) {
        if(member == null)
            return;
        lock.lock();
        try {
            if(responses.containsKey(member)) {
                responses.put(member, data);
                cond.signal(true);
            }
        }
        finally {
            lock.unlock();
        }
    }

    public void remove(Address member) {
        if(member == null)
            return;
        lock.lock();
        try {
            if(responses.remove(member) != null)
                cond.signal(true);
        }
        finally {
            lock.unlock();
        }
    }

    public void remove(List members) {
        if(members == null || members.isEmpty())
            return;
        lock.lock();
        try {
            for(Address member: members)
                responses.remove(member);
            cond.signal(true);
        }
        finally {
            lock.unlock();
        }
    }

    public void retainAll(List members) {
        if(members == null || members.isEmpty())
            return;
        lock.lock();
        try {
            if(responses.keySet().retainAll(members))
                cond.signal(true);
        }
        finally {
            lock.unlock();
        }
    }

    public void suspect(Address member) {
        remove(member);
    }

    public boolean isMet() {
        return hasAllResponses();
    }

    public boolean hasAllResponses() {
        lock.lock();
        try {
            if(responses.isEmpty())
                return true;
            for(Map.Entry entry: responses.entrySet()) {
                if(entry.getValue() == null)
                    return false;
            }
            return true;
        }
        finally {
            lock.unlock();
        }
    }

    public int numberOfValidResponses() {
        int retval=0;
        lock.lock();
        try {
            for(Map.Entry entry: responses.entrySet()) {
                if(entry.getValue() != null)
                    retval++;
            }
            return retval;
        }
        finally {
            lock.unlock();
        }
    }

    /** Returns a list of members which didn't send a valid response */
    public List getMissing() {
        List retval=new ArrayList();
        for(Map.Entry entry: responses.entrySet()) {
            if(entry.getValue() == null)
                retval.add(entry.getKey());
        }
        return retval;
    }

    public List getValidResults() {
        List retval=new ArrayList();
        for(Map.Entry entry: responses.entrySet()) {
            if(entry.getValue() != null)
                retval.add(entry.getKey());
        }
        return retval;
    }


    public Map getResults() {
        return responses;
    }

    public int size() {
        lock.lock();
        try {
            return responses.size();
        }
        finally {
            lock.unlock();
        }
    }


    /**
     * Waits until all responses have been received, or until a timeout has elapsed.
     * @param timeout Number of milliseconds to wait max. This value needs to be greater than 0, or else
     * it will be adjusted to 2000
     * @return boolean True if all responses have been received within timeout ms, else false (e.g. if interrupted)
     */
    public boolean waitForAllResponses(long timeout) {
        if(timeout <= 0)
            timeout=2000L;

        return cond.waitFor(this, timeout, TimeUnit.MILLISECONDS);
    }

    public void reset() {
        reset((Collection)null);
    }

    public void reset(Collection members) {
        lock.lock();
        try {
            responses.clear();
            if(members != null) {
                for(Address mbr: members)
                    responses.put(mbr, null);
            }
            cond.signal(true);
        }
        finally {
            lock.unlock();
        }
    }

    public void reset(Address ... members) {
        lock.lock();
        try {
            responses.clear();
            if(members != null) {
                for(Address mbr: members)
                    responses.put(mbr, null);
            }
            cond.signal(true);
        }
        finally {
            lock.unlock();
        }
    }



    public String toString() {
        StringBuilder sb=new StringBuilder();
        sb.append(responses).append(", complete=").append(hasAllResponses());
        return sb.toString();
    }


}