自定义流水号的autocode

时间:2022-08-26 14:19:44
package cn.com.do1.component.yopin.util;

import cn.com.do1.common.dac.QuickDAC;
import cn.com.do1.common.exception.BaseException;
import cn.com.do1.common.util.AssertUtil;
import cn.com.do1.dqdp.core.DqdpAppContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Map;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
*
* 自动编码工具类 <br/>调用 AutoCodeUtil.getAutoCode("传入编码前缀字符串")
* @author ao.ouyang
* 2015-4-23 10:00:17
*/
public final class AutoCodeUtil {
private final static Logger log = LoggerFactory.getLogger(AutoCodeUtil.class);
private final static ThreadLocal<Integer> executeCount = new ThreadLocal<Integer>(){
@Override
protected Integer initialValue() {
return 1;
}
};
private static DataSource ds;
private static AutoCodeUtil util;
private final static Lock lock = new ReentrantLock(true);

private AutoCodeUtil() {
ds = DqdpAppContext.getSpringContext().getBean(DataSource.class);
}

public static AutoCodeUtil getInstance() {
if (null == util) {
lock.lock();
try {
util = new AutoCodeUtil();
} finally {
lock.unlock();
}
}
return util;
}

/**
* 这个方法不能直接调用,因为没有加锁来控制并发
* @param type
* @return
* @throws BaseException
*/
private long getCurrentVal(String type) throws BaseException {
try {
Connection conn = ds.getConnection();
QuickDAC dac = null;
try {
dac = new QuickDAC(conn);
dac.preparedSql("select BEGINNING_VAL,INCREASE_STEP,CURRENT_VAL from tb_sequence t where t.val_type = UCASE(:type)");
dac.setPreValue("type", type);
Map<String, Long> query = dac.executeQuery();
if (!AssertUtil.isEmpty(query)) {
dac.preparedSql("update tb_sequence set current_val = case when current_val + increase_step > beginning_val then current_val + increase_step else beginning_val end where val_type = UCASE(:type)");
dac.setPreValue("type", type);
dac.executeUpdate();
return Math.max(query.get("CURRENT_VAL") + query.get("INCREASE_STEP"), query.get("BEGINNING_VAL"));
} else {
dac.preparedSql("insert into tb_sequence(val_type,current_val) values(UCASE(:type), :val)");
dac.setPreValue("type", type).setPreValue("val", 1);
dac.executeUpdate();
log.info("创建新的类别流水号:{}", type);
return 1L;
}
} finally {
if (null != dac)
dac.destoryWithoutConnection();
if (null != conn)
conn.close();
}
} catch (SQLException e) {
throw new BaseException(String.format("获取%s系统流水号失败", type), e);
}
}

private long getCurrentValAndLock(String type) throws BaseException {
try {
if (lock.tryLock(30, TimeUnit.MILLISECONDS)) {
try {
executeCount.set(0);
return this.getCurrentVal(type);
} finally {
lock.unlock();
}
} else {
log.warn("在指定的时间内未能获取指定类别的流水号:{}", type);
if (5 <= executeCount.get()) {
log.error("系统连续5次获取指定类别的流水号失败:{}", type);
return -1L;
}
executeCount.set(executeCount.get() + 1);
return getCurrentValAndLock(type);
}
} catch (InterruptedException e) {
throw new BaseException(e);
}
}

/**
* 流水号开头,不包括type这个类别标识,生成的流水号:00000002321
* @param type
* @param length
* @return
* @throws BaseException
*/
private String currentSequence(String type, int length) throws BaseException {
long value = getInstance().getCurrentValAndLock(type);
StringBuilder sb = new StringBuilder("0000000000000000000");
sb.append(value); //sb=00000000000000000001234567
sb.reverse(); //sb=76543210000000000000000000
sb.setLength(length); //sb=7654321000
return sb.reverse().toString(); //sb=0001234567
}

/**
* 按照指定类别名称,获取当前流水号,返回的流水号开头显示类别名称
* @param type 流水类别名称
* @return
* @throws BaseException
*/
public String currentSequence(String type) throws BaseException {
SimpleDateFormat sdf = new SimpleDateFormat("yyMMddHH");
return type + sdf.format(new Date()) + this.currentSequence(type, 5);
}

/**
* 按默认类别获取当前的流水号,返回的流水号开头不显示类别名称
* @return
* @throws BaseException
*/
public String currentSequence() throws BaseException {
SimpleDateFormat sdf = new SimpleDateFormat("yyMMddHH");
return sdf.format(new Date()) + this.currentSequence("default", 8);
}
}