ch.usi.da.dlog.message.Command.java Source code

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Here is the source code for ch.usi.da.dlog.message.Command.java

Source

package ch.usi.da.dlog.message;
/* 
 * Copyright (c) 2014 Universit della Svizzera italiana (USI)
 * 
 * This file is part of URingPaxos.
 *
 * URingPaxos is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * URingPaxos is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with URingPaxos.  If not, see <http://www.gnu.org/licenses/>.
 */

import org.apache.thrift.TDeserializer;
import org.apache.thrift.TException;
import org.apache.thrift.TSerializer;
import org.apache.thrift.protocol.TBinaryProtocol;

import ch.usi.da.dlog.thrift.gen.Cmd;
import ch.usi.da.dlog.thrift.gen.CmdType;

/**
 * Name: Command<br>
 * Description: <br>
 * 
 * Creation date: Apr 07, 2014<br>
 * $Id$
 * 
 * @author Samuel Benz benz@geoid.ch
 */
public class Command {

    private final int id;

    private final CommandType type;

    private final long position;

    private final byte[] value;

    private final int count;

    public Command(int id, CommandType type, long position, byte[] value) {
        this.id = id;
        this.type = type;
        this.position = position;
        this.value = value;
        this.count = -1;
    }

    public Command(int id, CommandType type, long position, byte[] value, int count) {
        this.id = id;
        this.type = type;
        this.position = position;
        this.value = value;
        this.count = count;
    }

    public int getID() {
        return id;
    }

    public CommandType getType() {
        return type;
    }

    public long getPosition() {
        return position;
    }

    public byte[] getValue() {
        return value;
    }

    public int getCount() {
        return count;
    }

    public String toString() {
        return ("Command id:" + id + " type:" + type + " position:" + position);
    }

    public boolean equals(Object obj) {
        if (obj instanceof Command) {
            if (this.hashCode() == ((Command) obj).hashCode()) {
                return true;
            }
        }
        return false;
    }

    public int hashCode() {
        return (int) (id + type.ordinal() + position);
    }

    public static Cmd toCmd(Command c) {
        Cmd cmd = new Cmd();
        cmd.setId(c.getID());
        cmd.setCount(c.getCount());
        switch (c.getType()) {
        case APPEND:
            cmd.setType(CmdType.APPEND);
            break;
        case MULTIAPPEND:
            cmd.setType(CmdType.MULTIAPPEND);
            break;
        case READ:
            cmd.setType(CmdType.READ);
            break;
        case TRIM:
            cmd.setType(CmdType.TRIM);
            break;
        case RESPONSE:
            cmd.setType(CmdType.RESPONSE);
            break;
        }
        cmd.setPosition(c.getPosition());
        cmd.setValue(c.getValue());
        return cmd;
    }

    public static byte[] toByteArray(Command c) {
        TSerializer serializer = new TSerializer(new TBinaryProtocol.Factory());
        Cmd cmd = toCmd(c);
        try {
            return serializer.serialize(cmd);
        } catch (TException e) {
            return new byte[0];
        }
    }

    public static Command toCommand(Cmd c) {
        CommandType type = null;
        switch (c.getType()) {
        case APPEND:
            type = CommandType.APPEND;
            break;
        case MULTIAPPEND:
            type = CommandType.MULTIAPPEND;
            break;
        case READ:
            type = CommandType.READ;
            break;
        case TRIM:
            type = CommandType.TRIM;
            break;
        case RESPONSE:
            type = CommandType.RESPONSE;
            break;
        }
        return new Command(c.getId(), type, c.getPosition(), c.getValue(), c.getCount());
    }

    public static Command fromByteArray(byte[] b) {
        TDeserializer deserializer = new TDeserializer(new TBinaryProtocol.Factory());
        Cmd c = new Cmd();
        try {
            deserializer.deserialize(c, b);
            if (c.type == null) {
                return null;
            }
        } catch (TException e) {
            return null;
        }
        return toCommand(c);
    }
}