Vesta發(fā)號(hào)器源碼解析——AbstractIdServiceImpl

這個(gè)類是Id生成的實(shí)現(xiàn)類的抽象類，主要的入口就在AbstractIdServiceImpl的系列類里面

字段

    //日志記錄
    protected final Logger log = LoggerFactory.getLogger(this.getClass());

    protected long machineId = -1;
    protected long genMethod = 0;
    protected long version = 0;
    
    //Id類型
    protected IdType idType;
    //Id元數(shù)據(jù)
    protected IdMeta idMeta;
    //Id轉(zhuǎn)換器
    protected IdConverter idConverter;
    //MachineId存儲(chǔ)
    protected MachineIdProvider machineIdProvider;
    //timer字段
    protected Timer timer;

構(gòu)造方法

    //默認(rèn)構(gòu)造方法
   public AbstractIdServiceImpl() {
        idType = IdType.SECONDS;
    }
    //按照給定的名稱初始化
    public AbstractIdServiceImpl(String type) {
        idType = IdType.parse(type);
    }
    //按照給定的類型值初始化
    public AbstractIdServiceImpl(long type) {
        idType = IdType.parse(type);
    }
    //按照給定的枚舉類初始化
    public AbstractIdServiceImpl(IdType type) {
        idType = type;
    }

初始化方法

    public void init() {
        //如果id元數(shù)據(jù)沒有初始化，利用工廠初始化id元數(shù)據(jù)
        if (this.idMeta == null) {
            setIdMeta(IdMetaFactory.getIdMeta(idType));
        }
        //Id轉(zhuǎn)換器如果沒有初始化按照默認(rèn)的初始化
        if (this.idConverter == null) {
            setIdConverter(new IdConverterImpl());
        }
        //timer如果沒有初始化，按默認(rèn)的實(shí)例化
        if (this.timer == null) {
            setTimer(new SimpleTimer());
        }
        //初始化，元數(shù)據(jù)和類型
        this.timer.init(idMeta, idType);
        //初始化machineID
        this.machineId = machineIdProvider.getMachineId();
        //校驗(yàn)machineid
        validateMachineId(this.machineId);
    }

校驗(yàn)MachineId

方法主要用于校驗(yàn)MachineId

    public void validateMachineId(long machineId){
        //MachineId小于0，說明沒有配置，停止啟動(dòng)拋出異常記錄日志
        if (machineId < 0) {
            log.error("The machine ID is not configured properly (" + machineId + " < 0) so that Vesta Service refuses to start.");

            throw new IllegalStateException(
                    "The machine ID is not configured properly (" + machineId + " < 0) so that Vesta Service refuses to start.");
        //machineId超過了最大的MachineId的標(biāo)示范圍，停止啟動(dòng)，拋出異常
        } else if (machineId >= (1 << this.idMeta.getMachineBits())) {
            log.error("The machine ID is not configured properly ("
                    + machineId + " >= " + (1 << this.idMeta.getMachineBits()) + ") so that Vesta Service refuses to start.");

            throw new IllegalStateException("The machine ID is not configured properly ("
                    + machineId + " >= " + (1 << this.idMeta.getMachineBits()) + ") so that Vesta Service refuses to start.");

        }
    }

核心方法 生成id

    public long genId() {
        Id id = new Id();
        //對(duì)ID進(jìn)行基本信息配置
        id.setMachine(machineId);
        id.setGenMethod(genMethod);
        id.setType(idType.value());
        id.setVersion(version);
        //生成變化字段，一個(gè)是時(shí)間一個(gè)是序列
        populateId(id);
        //將Id對(duì)象轉(zhuǎn)換成long型的
        long ret = idConverter.convert(id, this.idMeta);

        // 記錄日志
        if (log.isTraceEnabled())
            log.trace(String.format("Id: %s => %d", id, ret));

        return ret;
    }

其他方法

具體作用詳見各方法注釋

    //Id主要變化生成方法，實(shí)現(xiàn)類中實(shí)現(xiàn)
    protected abstract void populateId(Id id);
    //轉(zhuǎn)換時(shí)間，將long時(shí)間轉(zhuǎn)換為date
    public Date transTime(final long time) {
        return timer.transTime(time);
    }

    //解析Id，本質(zhì)上是調(diào)用轉(zhuǎn)換方法
    //將long轉(zhuǎn)換為Id對(duì)象
    public Id expId(long id) {
        return idConverter.convert(id, this.idMeta);
    }
    
    //構(gòu)建一個(gè)指定的ID，主要參數(shù)是時(shí)間和序列號(hào)
    public long makeId(long time, long seq) {
        return makeId(time, seq, machineId);
    }

    //構(gòu)建一個(gè)指定的ID，主要參數(shù)是時(shí)間和序列號(hào)以及machineid
    public long makeId(long time, long seq, long machine) {
        return makeId(genMethod, time, seq, machine);
    }
    
    //構(gòu)建一個(gè)指定的ID，主要參數(shù)是生成方法、時(shí)間和序列號(hào)以及machineid
    public long makeId(long genMethod, long time, long seq, long machine) {
        return makeId(idType.value(), genMethod, time, seq, machine);
    }
    
    //構(gòu)建一個(gè)指定的ID，主要參數(shù)是類型、生成方法、時(shí)間和序列號(hào)以及machineid
    public long makeId(long type, long genMethod, long time,
                       long seq, long machine) {
        return makeId(version, type, genMethod, time, seq, machine);
    }

    //構(gòu)建一個(gè)指定的ID，主要參數(shù)是版本、類型、生成方法、時(shí)間和序列號(hào)以及machineid
    public long makeId(long version, long type, long genMethod,
                       long time, long seq, long machine) {
        Id id = new Id(machine, seq, time, genMethod, type, version);
        return idConverter.convert(id, this.idMeta);
    }
    
    //下面是相關(guān)字段的get和set方法
    public void setMachineId(long machineId) {
        this.machineId = machineId;
    }

    public void setGenMethod(long genMethod) {
        this.genMethod = genMethod;
    }

    public void setVersion(long version) {
        this.version = version;
    }

    public void setIdConverter(IdConverter idConverter) {
        this.idConverter = idConverter;
    }

    public void setIdMeta(IdMeta idMeta) {
        this.idMeta = idMeta;
    }

    public void setMachineIdProvider(MachineIdProvider machineIdProvider) {
        this.machineIdProvider = machineIdProvider;
    }

    public void setTimer(Timer timer) {
        this.timer = timer;
    }