一、上文我們已經(jīng)完成了創(chuàng)建common子模塊
接下來我們在里面創(chuàng)建返回實體類
新建 entry包

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public Result() {
}

public Result(boolean flag, Integer code, String message) {
    this.flag = flag;
    this.code = code;
    this.message = message;
}

public Result(boolean flag, Integer code, String message, Object data) {
    this.flag = flag;
    this.code = code;
    this.message = message;
    this.data = data;
}

public boolean isFlag() {
    return flag;
}

public void setFlag(boolean flag) {
    this.flag = flag;
}

public Integer getCode() {
    return code;
}

public void setCode(Integer code) {
    this.code = code;
}

public String getMessage() {
    return message;
}

public void setMessage(String message) {
    this.message = message;
}

public Object getData() {
    return data;
}

public void setData(Object data) {
    this.data = data;
}

這里面我們使用很原始的set get 也可以使用lombook 通過注釋來完成 實體的一些操作微驶。

接下來創(chuàng)建分頁結(jié)果類：

public class PageResult <T>{
private Long total;
private List<T> rows;

public PageResult() {
}

public PageResult(Long total, List<T> rows) {
    this.total = total;
    this.rows = rows;
}

public Long getTotal() {
    return total;
}

public void setTotal(Long total) {
    this.total = total;
}

public List<T> getRows() {
    return rows;
}

public void setRows(List<T> rows) {
    this.rows = rows;
}

}
接下來 創(chuàng)建狀態(tài)碼實體類 ：
public class StatusCode {
/**
* 成功
/
public static final int OK=20000;
/*
* 失敗
/
public static final int ERROR =20001;
/*
* 用戶名或密碼錯誤
/
public static final int LOGINERROR =20002;
/*
* 權(quán)限不足
/
public static final int ACCESSERROR =20003;
/*
* 遠(yuǎn)程調(diào)用失敗
/
public static final int REMOTEERROR =20004;
/*
* 重復(fù)操作
/
public static final int REPERROR =20005;
/*
* 驗證碼過期
*/
public static final int VERIFICATION =20006;
}

接下來我們需要解除一個新的分布式的ID生成器：

image.png

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在 comnon包下創(chuàng)建 util包

image.png

IdWorker 代碼如下: 我們直接引用這個代碼 直接來使用：
package util;

import java.lang.management.ManagementFactory;
import java.net.InetAddress;
import java.net.NetworkInterface;

/**

• <p>名稱：IdWorker.java</p>

• <p>描述：分布式自增長ID</p>

• <pre>

• Twitter的 Snowflake　JAVA實現(xiàn)方案
  

• </pre>

• 核心代碼為其IdWorker這個類實現(xiàn)浪谴，其原理結(jié)構(gòu)如下，我分別用一個0表示一位因苹，用—分割開部分的作用：

• 1||0---0000000000 0000000000 0000000000 0000000000 0 --- 00000 ---00000 ---000000000000

• 在上面的字符串中苟耻，第一位為未使用（實際上也可作為long的符號位），接下來的41位為毫秒級時間扶檐，

• 然后5位datacenter標(biāo)識位凶杖，5位機器ID（并不算標(biāo)識符，實際是為線程標(biāo)識）款筑，

• 然后12位該毫秒內(nèi)的當(dāng)前毫秒內(nèi)的計數(shù)智蝠，加起來剛好64位，為一個Long型奈梳。

• 這樣的好處是杈湾，整體上按照時間自增排序，并且整個分布式系統(tǒng)內(nèi)不會產(chǎn)生ID碰撞（由datacenter和機器ID作區(qū)分）攘须，

• 并且效率較高漆撞，經(jīng)測試，snowflake每秒能夠產(chǎn)生26萬ID左右于宙，完全滿足需要浮驳。

• <p>

• 64位ID (42(毫秒)+5(機器ID)+5(業(yè)務(wù)編碼)+12(重復(fù)累加))

• @author Polim
  /
  public class IdWorker {
  /*

  • 時間起始標(biāo)記點，作為基準(zhǔn)捞魁，一般取系統(tǒng)的最近時間（一旦確定不能變動）
    /
    private final static long twepoch = 1288834974657L;
    /*
  • 機器標(biāo)識位數(shù)
    /
    private final static long workerIdBits = 5L;
    /*
  • 數(shù)據(jù)中心標(biāo)識位數(shù)
    /
    private final static long datacenterIdBits = 5L;
    /*
  • 機器ID最大值
    /
    private final static long maxWorkerId = -1L ^ (-1L << workerIdBits);
    /*
  • 數(shù)據(jù)中心ID最大值
    /
    private final static long maxDatacenterId = -1L ^ (-1L << datacenterIdBits);
    /*
  • 毫秒內(nèi)自增位
    /
    private final static long sequenceBits = 12L;
    /*
  • 機器ID偏左移12位
    /
    private final static long workerIdShift = sequenceBits;
    /*
  • 數(shù)據(jù)中心ID左移17位
    /
    private final static long datacenterIdShift = sequenceBits + workerIdBits;
    /*
  • 時間毫秒左移22位
    */
    private final static long timestampLeftShift = sequenceBits + workerIdBits + datacenterIdBits;

  private final static long sequenceMask = -1L ^ (-1L << sequenceBits);
  /**

  • 上次生產(chǎn)id時間戳
    /
    private static long lastTimestamp = -1L;
    /*
  • 0抹恳，并發(fā)控制
    /
    private long sequence = 0L;
    /*
  • 工作機器ID
    /
    private final long workerId;
    /*
  • 數(shù)據(jù)標(biāo)識id部分
    */
    private final long datacenterId;

  public IdWorker() {
  this.datacenterId = getDatacenterId(maxDatacenterId);
  this.workerId = getMaxWorkerId(datacenterId, maxWorkerId);
  }

  /**

  • @param workerId 工作機器ID
  • @param datacenterId 序列號
    */
    public IdWorker(long workerId, long datacenterId) {
    if (workerId > maxWorkerId || workerId < 0) {
    throw new IllegalArgumentException(String.format("worker Id can't be greater than %d or less than 0", maxWorkerId));
    }
    if (datacenterId > maxDatacenterId || datacenterId < 0) {
    throw new IllegalArgumentException(String.format("datacenter Id can't be greater than %d or less than 0", maxDatacenterId));
    }
    this.workerId = workerId;
    this.datacenterId = datacenterId;
    }

  /**

  • 獲取下一個ID

  • @return
    */
    public synchronized long nextId() {
    long timestamp = timeGen();
    if (timestamp < lastTimestamp) {
    throw new RuntimeException(String.format("Clock moved backwards. Refusing to generate id for %d milliseconds", lastTimestamp - timestamp));
    }

    if (lastTimestamp == timestamp) {
    // 當(dāng)前毫秒內(nèi)，則+1
    sequence = (sequence + 1) & sequenceMask;
    if (sequence == 0) {
    // 當(dāng)前毫秒內(nèi)計數(shù)滿了署驻，則等待下一秒
    timestamp = tilNextMillis(lastTimestamp);
    }
    } else {
    sequence = 0L;
    }
    lastTimestamp = timestamp;
    // ID偏移組合生成最終的ID奋献，并返回ID
    long nextId = ((timestamp - twepoch) << timestampLeftShift)
    | (datacenterId << datacenterIdShift)
    | (workerId << workerIdShift) | sequence;

    return nextId;
    }

  private long tilNextMillis(final long lastTimestamp) {
  long timestamp = this.timeGen();
  while (timestamp <= lastTimestamp) {
  timestamp = this.timeGen();
  }
  return timestamp;
  }

  private long timeGen() {
  return System.currentTimeMillis();
  }

  /**

  • <p>
  • 獲取 maxWorkerId
  • </p>
    /
    protected static long getMaxWorkerId(long datacenterId, long maxWorkerId) {
    StringBuffer mpid = new StringBuffer();
    mpid.append(datacenterId);
    String name = ManagementFactory.getRuntimeMXBean().getName();
    if (!name.isEmpty()) {
    /
    * GET jvmPid
    /
    mpid.append(name.split("@")[0]);
    }
    /
    • MAC + PID 的 hashcode 獲取16個低位
      */
      return (mpid.toString().hashCode() & 0xffff) % (maxWorkerId + 1);
      }

  /**

  • <p>
  • 數(shù)據(jù)標(biāo)識id部分
  • </p>
    */
    protected static long getDatacenterId(long maxDatacenterId) {
    long id = 0L;
    try {
    InetAddress ip = InetAddress.getLocalHost();
    NetworkInterface network = NetworkInterface.getByInetAddress(ip);
    if (network == null) {
    id = 1L;
    } else {
    byte[] mac = network.getHardwareAddress();
    id = ((0x000000FF & (long) mac[mac.length - 1])
    | (0x0000FF00 & (((long) mac[mac.length - 2]) << 8))) >> 6;
    id = id % (maxDatacenterId + 1);
    }
    } catch (Exception e) {
    System.out.println(" getDatacenterId: " + e.getMessage());
    }
    return id;
    }

}