Ziele Untersuchung
mit Columbo Integrität von
Datenbanken Interaktion und
Portierbarkeit Ergonomie der
Schnittstellen

Angebot Produkte Projekt Beratung

Mittel Analytik Modellierung Sprachen Algebra Logik Hardware Denken Kreativität

Zusammenhänge Gesellschaft Wirtschaft Branche Firma


products/Sources/formale Sprachen/Java/Tomcat/java/org/apache/catalina/tribes/group/ (Apache Software Stiftung Version 2.4.65^©) Datei vom 10.10.2023 mit Größe 11 kB

Quelle RpcChannel.java Sprache: JAVA

/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements.  See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License.  You may obtain a copy of the License at
*
*      http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.catalina.tribes.group;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

import org.apache.catalina.tribes.Channel;
import org.apache.catalina.tribes.ChannelException;
import org.apache.catalina.tribes.ChannelListener;
import org.apache.catalina.tribes.ErrorHandler;
import org.apache.catalina.tribes.Member;
import org.apache.catalina.tribes.UniqueId;
import org.apache.catalina.tribes.util.StringManager;
import org.apache.catalina.tribes.util.UUIDGenerator;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;

/**
* A channel to handle RPC messaging
*/
public class RpcChannel implements ChannelListener {
    private static final Log log = LogFactory.getLog(RpcChannel.class);
    protected static final StringManager sm = StringManager.getManager(RpcChannel.class);

    public static final int FIRST_REPLY = 1;
    public static final int MAJORITY_REPLY = 2;
    public static final int ALL_REPLY = 3;
    public static final int NO_REPLY = 4;

    private Channel channel;
    private RpcCallback callback;
    private byte[] rpcId;
    private int replyMessageOptions = 0;

    private final ConcurrentMap<RpcCollectorKey, RpcCollector> responseMap = new ConcurrentHashMap<>();

    /**
     * Create an RPC channel. You can have several RPC channels attached to a group
     * all separated out by the uniqueness
     * @param rpcId - the unique Id for this RPC group
     * @param channel Channel
     * @param callback RpcCallback
     */
    public RpcChannel(byte[] rpcId, Channel channel, RpcCallback callback) {
        this.channel = channel;
        this.callback = callback;
        this.rpcId = rpcId;
        channel.addChannelListener(this);
    }

    /**
     * Send a message and wait for the response.
     * @param destination Member[] - the destination for the message, and the members you request a reply from
     * @param message Serializable - the message you are sending out
     * @param rpcOptions int - FIRST_REPLY, MAJORITY_REPLY or ALL_REPLY
     * @param channelOptions channel sender options
     * @param timeout long - timeout in milliseconds, if no reply is received within this time null is returned
     * @return Response[] - an array of response objects.
     * @throws ChannelException Error sending message
     */
    public Response[] send(Member[] destination,
                           Serializable message,
                           int rpcOptions,
                           int channelOptions,
                           long timeout) throws ChannelException {

        if ( destination==null || destination.length == 0 ) {
            return new Response[0];
        }

        //avoid dead lock
        int sendOptions =
            channelOptions & ~Channel.SEND_OPTIONS_SYNCHRONIZED_ACK;

        RpcCollectorKey key = new RpcCollectorKey(UUIDGenerator.randomUUID(false));
        RpcCollector collector = new RpcCollector(key,rpcOptions,destination.length);
        try {
            synchronized (collector) {
                if ( rpcOptions != NO_REPLY ) {
                    responseMap.put(key, collector);
                }
                RpcMessage rmsg = new RpcMessage(rpcId, key.id, message);
                channel.send(destination, rmsg, sendOptions);
                if ( rpcOptions != NO_REPLY ) {
                    collector.wait(timeout);
                }
            }
        } catch ( InterruptedException ix ) {
            Thread.currentThread().interrupt();
        } finally {
            responseMap.remove(key);
        }
        return collector.getResponses();
    }

    @Override
    public void messageReceived(Serializable msg, Member sender) {
        RpcMessage rmsg = (RpcMessage)msg;
        RpcCollectorKey key = new RpcCollectorKey(rmsg.uuid);
        if ( rmsg.reply ) {
            RpcCollector collector = responseMap.get(key);
            if (collector == null) {
                if (!(rmsg instanceof RpcMessage.NoRpcChannelReply)) {
                    callback.leftOver(rmsg.message, sender);
                }
            } else {
                synchronized (collector) {
                    //make sure it hasn't been removed
                    if ( responseMap.containsKey(key) ) {
                        if ( (rmsg instanceof RpcMessage.NoRpcChannelReply) ) {
                            collector.destcnt--;
                        } else {
                            collector.addResponse(rmsg.message, sender);
                        }
                        if (collector.isComplete()) {
                            collector.notifyAll();
                        }
                    } else {
                        if (! (rmsg instanceof RpcMessage.NoRpcChannelReply) ) {
                            callback.leftOver(rmsg.message, sender);
                        }
                    }
                }//synchronized
            }//end if
        } else {
            boolean finished = false;
            final ExtendedRpcCallback excallback = (callback instanceof ExtendedRpcCallback)?((ExtendedRpcCallback)callback) : null;
            boolean asyncReply = ((replyMessageOptions & Channel.SEND_OPTIONS_ASYNCHRONOUS) == Channel.SEND_OPTIONS_ASYNCHRONOUS);
            Serializable reply = callback.replyRequest(rmsg.message,sender);
            ErrorHandler handler = null;
            final Serializable request = msg;
            final Serializable response = reply;
            final Member fsender = sender;
            if (excallback!=null && asyncReply) {
                handler = new ErrorHandler() {
                    @Override
                    public void handleError(ChannelException x, UniqueId id) {
                        excallback.replyFailed(request, response, fsender, x);
                    }
                    @Override
                    public void handleCompletion(UniqueId id) {
                        excallback.replySucceeded(request, response, fsender);
                    }
                };
            }
            rmsg.reply = true;
            rmsg.message = reply;
            try {
                if (handler!=null) {
                    channel.send(new Member[] {sender}, rmsg,replyMessageOptions & ~Channel.SEND_OPTIONS_SYNCHRONIZED_ACK, handler);
                } else {
                    channel.send(new Member[] {sender}, rmsg,replyMessageOptions & ~Channel.SEND_OPTIONS_SYNCHRONIZED_ACK);
                }
                finished = true;
            } catch ( Exception x )  {
                if (excallback != null && !asyncReply) {
                    excallback.replyFailed(rmsg.message, reply, sender, x);
                } else {
                    log.error(sm.getString("rpcChannel.replyFailed"),x);
                }
            }
            if (finished && excallback != null && !asyncReply) {
                excallback.replySucceeded(rmsg.message, reply, sender);
            }
        }//end if
    }

    public void breakdown() {
        channel.removeChannelListener(this);
    }

    @Override
    public boolean accept(Serializable msg, Member sender) {
        if ( msg instanceof RpcMessage ) {
            RpcMessage rmsg = (RpcMessage)msg;
            return Arrays.equals(rmsg.rpcId,rpcId);
        } else {
            return false;
        }
    }

    public Channel getChannel() {
        return channel;
    }

    public RpcCallback getCallback() {
        return callback;
    }

    public byte[] getRpcId() {
        return rpcId;
    }

    public void setChannel(Channel channel) {
        this.channel = channel;
    }

    public void setCallback(RpcCallback callback) {
        this.callback = callback;
    }

    public void setRpcId(byte[] rpcId) {
        this.rpcId = rpcId;
    }

    public int getReplyMessageOptions() {
        return replyMessageOptions;
    }

    public void setReplyMessageOptions(int replyMessageOptions) {
        this.replyMessageOptions = replyMessageOptions;
    }

    /**
     * Class that holds all response.
     */
    public static class RpcCollector {
        public final ArrayList<Response> responses = new ArrayList<>();
        public final RpcCollectorKey key;
        public final int options;
        public int destcnt;

        public RpcCollector(RpcCollectorKey key, int options, int destcnt) {
            this.key = key;
            this.options = options;
            this.destcnt = destcnt;
        }

        public void addResponse(Serializable message, Member sender) {
            Response resp = new Response(sender,message);
            responses.add(resp);
        }

        public boolean isComplete() {
            if ( destcnt <= 0 ) {
                return true;
            }
            switch (options) {
                case ALL_REPLY:
                    return destcnt == responses.size();
                case MAJORITY_REPLY:
                    float perc = ((float)responses.size()) / ((float)destcnt);
                    return perc >= 0.50f;
                case FIRST_REPLY:
                    return responses.size()>0;
                default:
                    return false;
            }
        }

        @Override
        public int hashCode() {
            return key.hashCode();
        }

        @Override
        public boolean equals(Object o) {
            if ( o instanceof RpcCollector ) {
                RpcCollector r = (RpcCollector)o;
                return r.key.equals(this.key);
            } else {
                return false;
            }
        }

        public Response[] getResponses() {
            return responses.toArray(new Response[0]);
        }
    }

    public static class RpcCollectorKey {
        final byte[] id;
        public RpcCollectorKey(byte[] id) {
            this.id = id;
        }

        @Override
        public int hashCode() {
            return id[0]+id[1]+id[2]+id[3];
        }

        @Override
        public boolean equals(Object o) {
            if ( o instanceof RpcCollectorKey ) {
                RpcCollectorKey r = (RpcCollectorKey)o;
                return Arrays.equals(id,r.id);
            } else {
                return false;
            }
        }

    }
}

quality97%

¤ Dauer der Verarbeitung: 0.13 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.