使用入门-数据源配置

  • 数据源配置，tddl的入口，从datasource切入
  1. <bean id="tddlDataSource" class="com.taobao.tddl.client.jdbc.TDataSource" init-method="init">
  2.     <property name="appName" value="tddl_sample" />
  3.     <property name="dynamicRule" value="true"/>
  4. </bean>
  • Sequence生成器
  1. <bean id="seqStudent" class="com.taobao.tddl.client.sequence.impl.GroupSequence" init-method="init">
  2. 	<property name="sequenceDao" ref="idSequenceDao" />
  3. 	<property name="name" value="seq_Student" />
  4. </bean>
  • 指定静态文件，3.0以后支持动态推送
  1. <bean id="myDataSource" class="com.taobao.tddl.client.jdbc.TDataSource" init-method="init">
  2.     <property name="appName" value="tddl_sample"/>
  3.     <property name="appRuleFile" value="classpath:tddl-rule.xml"/>
  4.     <property name="useLocalConfig" value="true"/>
  5. </bean>

myDataSource--分库分表数据源

appName--数据库代号从dba获得

appRuleFile--分库分表配置文件

useLocalConfig--使用本地配置

  • Sequence配置:  tddl-sequence.xml
  1. <bean id="sequenceDao" class="com.taobao.tddl.client.sequence.impl.GroupSequenceDao" init-method="init">
  2.     <!-- appName，必填 -->
  3.     <property name="appName" value="CUNTAO_SUPPLIER_APP" />
  4.     <!-- 数据源的个数 -->
  5.     <property name="dscount" value="1" />
  6.     <!-- dbGroupKeys 必填 -->
  7.     <!-- 如果在末尾插入"-OFF",该源将被关掉，该源占据的SQL段会被保留" -->
  8.     <!-- 当dbGroupKeys中配置的个数小于dbcount的值的时候，默认配置了"-OFF"的源 -->
  9.     <property name="dbGroupKeys">
  10.         <list>
  11.             <value>CUNTAO_SUPPLIER_BODY00_GROUP</value>
  12.         </list>
  13.     </property>
  14.     <!-- 内步长 ,默认为1000，取值在1-100000之间 -->
  15.     <property name="innerStep" value="500" />
  16.     <!-- 重试次数，在多个groupDataSource的场景下，建议设置成1-2次。默认为2次 -->
  17.     <property name="retryTimes" value="2" />
  18.     <!-- sequence表的表名 -->
  19.     <property name="tableName" value="cuntao_supplier_sequence" />
  20.     <!-- 自适应开关 ,默认为false -->
  21.     <property name="adjust" value="true" />
  22. </bean>

TDDL分库分表配置bean

tddl-rule.xml

  1. <?xml version="1.0" encoding="UTF-8" ?>
  2. <beans
  3.     xmlns="http://www.springframework.org/schema/beans"
  4.     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  5.     xmlns:aop="http://www.springframework.org/schema/aop"
  6.     xmlns:tx="http://www.springframework.org/schema/tx"
  7. xsi:schemaLocation="
  8. http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
  9. http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
  10. http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">
  11.     <bean id="vtabroot" class="com.taobao.tddl.interact.rule.VirtualTableRoot" init-method="init">
  12.         <property name="defaultDbIndex" value="CUNTAO_SUPPLIER_GROUP"/>
  13.         <property name="dbType" value="MYSQL"/>
  14.         <property name="tableRules">
  15.             <map>
  16.                 <entry key="cuntao_purchase_order" value-ref="cuntao_purchase_order_bean"/>
  17.                 <entry key="cuntao_sub_purchase_order" value-ref="cuntao_sub_purchase_order_bean"/>
  18.                 <entry key="cuntao_logistics_order" value-ref="cuntao_logistics_order_bean"/>
  19.                 <entry key="cuntao_sub_logistics_order" value-ref="cuntao_sub_logistics_order_bean"/>
  20.             </map>
  21.         </property>
  22.     </bean>
  23.     <bean id="cuntao_purchase_order_bean" class="com.taobao.tddl.interact.rule.TableRule">
  24.         <property name="dbNamePattern" value="CUNTAO_SUPPLIER_BODY{00}_GROUP"/>
  25.         <property name="dbRuleArray">
  26.             <value>(#supplier_id,1,256#.longValue() % 10000 % 256).intdiv(32)</value>
  27.         </property>
  28.         <property name="tbNamePattern" value="cuntao_purchase_order_{0000}" />
  29.         <property name="tbRuleArray">
  30.             <value>#supplier_id,1,256#.longValue() % 10000 % 256</value>
  31.         </property>
  32.     </bean>
  33. </beans>

　　

配置项说明
分表总配置VirtualTableRoot:
其中，defaultDbIndex是appgroup，从DBA获取;dbType，数据库类型;tableRules引入各个表的配置

分库分表配置TableRule;其中，dbNamePattern分库规则，大括号会替换成dbRuleArray中的值.
dbRuleArray，分库计算方法，(#supplier_id,1,256#.longValue() % 10000 % 256).intdiv(32)表示以supplier_id为分表键，256张表，8个库所以除以32，我们计算规则取后四位计算所以先模10000.

tbNamePattern分表规则，大括号会替换成tbRuleArray中的值。
dbRuleArray，分表计算方法，#supplier_id,1,256#.longValue() % 10000 % 256 就是分库计算方法不除以32.

sequence生成bean
我们用的sequence是一个单库单表的数据库，即每次使用GroupSequence获取新的seq值来计算id，保证全局各个表不会发生id冲突。

appName，从DBA获得。

dbGroupKeys，所在库名称

tableName，sequence表名，可以使用一个sequence表来计算多个表的id，因为每个表实际只占用一行数据。

name，目标表在sequence表中的key，一般取表名，其实是任意的。

  • DefaultSequenceDao源码
  1. public class DefaultSequenceDao implements SequenceDao
  2. {
  3.   private static final Log log = LogFactory.getLog(DefaultSequenceDao.class);
  4.   private static final int MIN_STEP = 1;
  5.   private static final int MAX_STEP = 100000;
  6.   private static final int DEFAULT_STEP = 1000;
  7.   private static final int DEFAULT_RETRY_TIMES = 150;
  8.   private static final String DEFAULT_TABLE_NAME = "sequence";
  9.   private static final String DEFAULT_NAME_COLUMN_NAME = "name";
  10.   private static final String DEFAULT_VALUE_COLUMN_NAME = "value";
  11.   private static final String DEFAULT_GMT_MODIFIED_COLUMN_NAME = "gmt_modified";
  12.   private static final long DELTA = 100000000L;
  13.   private DataSource dataSource;
  14.   private int retryTimes = 150;
  15.   private int step = 1000;
  16.   private String tableName = "sequence";
  17.   private String nameColumnName = "name";
  18.   private String valueColumnName = "value";
  19.   private String gmtModifiedColumnName = "gmt_modified";
  20.   private volatile String selectSql;
  21.   private volatile String updateSql;
  22.  
  23.   public SequenceRange nextRange(String name)
  24.     throws SequenceException
  25.   {
  26.     if (name == null) {
  27.       throw new IllegalArgumentException("序列名称不能为空");
  28.     }
  29.  
  30.     Connection conn = null;
  31.     PreparedStatement stmt = null;
  32.     ResultSet rs = null;
  33.  
  34.     for (int i = 0; i < this.retryTimes + 1; i++) { long oldValue;
  35.       long newValue;
  36.       try { conn = this.dataSource.getConnection();
  37.         stmt = conn.prepareStatement(getSelectSql());
  38.         stmt.setString(1, name);
  39.         rs = stmt.executeQuery();
  40.         rs.next();
  41.         oldValue = rs.getLong(1);
  42.  
  43.         if (oldValue < 0L) {
  44.           StringBuilder message = new StringBuilder();
  45.           message.append("Sequence value cannot be less than zero, value = ").append(oldValue);
  46.           message.append(", please check table ").append(getTableName());
  47.  
  48.           throw new SequenceException(message.toString());
  49.         }
  50.  
  51.         if (oldValue > 9223372036754775807L) {
  52.           StringBuilder message = new StringBuilder();
  53.           message.append("Sequence value overflow, value = ").append(oldValue);
  54.           message.append(", please check table ").append(getTableName());
  55.  
  56.           throw new SequenceException(message.toString());
  57.         }
  58.  
  59.         newValue = oldValue + getStep();
  60.       } catch (SQLException e) {
  61.         throw new SequenceException(e);
  62.       } finally {
  63.         closeResultSet(rs);
  64.         rs = null;
  65.         closeStatement(stmt);
  66.         stmt = null;
  67.         closeConnection(conn);
  68.         conn = null;
  69.       }
  70.       try
  71.       {
  72.         conn = this.dataSource.getConnection();
  73.         stmt = conn.prepareStatement(getUpdateSql());
  74.         stmt.setLong(1, newValue);
  75.         stmt.setTimestamp(2, new Timestamp(System.currentTimeMillis()));
  76.         stmt.setString(3, name);
  77.         stmt.setLong(4, oldValue);
  78.         int affectedRows = stmt.executeUpdate();
  79.         if (affectedRows == 0)
  80.         {
  81.           closeStatement(stmt);
  82.           stmt = null;
  83.           closeConnection(conn);
  84.           conn = null;
  85.         }
  86.         else
  87.         {
  88.           return new SequenceRange(oldValue + 1L, newValue);
  89.         }
  90.       } catch (SQLException e) { throw new SequenceException(e);
  91.       } finally {
  92.         closeStatement(stmt);
  93.         stmt = null;
  94.         closeConnection(conn);
  95.         conn = null;
  96.       }
  97.     }
  98.  
  99.     throw new SequenceException("Retried too many times, retryTimes = " + this.retryTimes);
  100.   }
  101.  
  102.   private String getSelectSql() {
  103.     if (this.selectSql == null) {
  104.       synchronized (this) {
  105.         if (this.selectSql == null) {
  106.           StringBuilder buffer = new StringBuilder();
  107.           buffer.append("select ").append(getValueColumnName());
  108.           buffer.append(" from ").append(getTableName());
  109.           buffer.append(" where ").append(getNameColumnName()).append(" = ?");
  110.  
  111.           this.selectSql = buffer.toString();
  112.         }
  113.       }
  114.     }
  115.  
  116.     return this.selectSql;
  117.   }
  118.  
  119.   private String getUpdateSql() {
  120.     if (this.updateSql == null) {
  121.       synchronized (this) {
  122.         if (this.updateSql == null) {
  123.           StringBuilder buffer = new StringBuilder();
  124.           buffer.append("update ").append(getTableName());
  125.           buffer.append(" set ").append(getValueColumnName()).append(" = ?, ");
  126.           buffer.append(getGmtModifiedColumnName()).append(" = ? where ");
  127.           buffer.append(getNameColumnName()).append(" = ? and ");
  128.           buffer.append(getValueColumnName()).append(" = ?");
  129.  
  130.           this.updateSql = buffer.toString();
  131.         }
  132.       }
  133.     }
  134.  
  135.     return this.updateSql;
  136.   }
  137.  
  138.   private static void closeResultSet(ResultSet rs) {
  139.     if (rs != null)
  140.       try {
  141.         rs.close();
  142.       } catch (SQLException e) {
  143.         log.debug("Could not close JDBC ResultSet", e);
  144.       } catch (Throwable e) {
  145.         log.debug("Unexpected exception on closing JDBC ResultSet", e);
  146.       }
  147.   }
  148.  
  149.   private static void closeStatement(Statement stmt)
  150.   {
  151.     if (stmt != null)
  152.       try {
  153.         stmt.close();
  154.       } catch (SQLException e) {
  155.         log.debug("Could not close JDBC Statement", e);
  156.       } catch (Throwable e) {
  157.         log.debug("Unexpected exception on closing JDBC Statement", e);
  158.       }
  159.   }
  160.  
  161.   private static void closeConnection(Connection conn)
  162.   {
  163.     if (conn != null)
  164.       try {
  165.         conn.close();
  166.       } catch (SQLException e) {
  167.         log.debug("Could not close JDBC Connection", e);
  168.       } catch (Throwable e) {
  169.         log.debug("Unexpected exception on closing JDBC Connection", e);
  170.       }
  171.   }
  172.  
  173.  ...
  • GroupSequenceDao源码
  1. public class GroupSequenceDao implements SequenceDao
  2. {
  3.   private static final Log log = LogFactory.getLog(GroupSequenceDao.class);
  4.   private static final int MIN_STEP = 1;
  5.   private static final int MAX_STEP = 100000;
  6.   private static final int DEFAULT_INNER_STEP = 1000;
  7.   private static final int DEFAULT_RETRY_TIMES = 2;
  8.   private static final String DEFAULT_TABLE_NAME = "sequence";
  9.   private static final String DEFAULT_NAME_COLUMN_NAME = "name";
  10.   private static final String DEFAULT_VALUE_COLUMN_NAME = "value";
  11.   private static final String DEFAULT_GMT_MODIFIED_COLUMN_NAME = "gmt_modified";
  12.   private static final int DEFAULT_DSCOUNT = 2;
  13.   private static final Boolean DEFAULT_ADJUST = Boolean.valueOf(false);
  14.   private static final long DELTA = 100000000L;
  15.   private String appName;
  16.   private List<String> dbGroupKeys;
  17.   private Map<String, DataSource> dataSourceMap;
  18.   private boolean adjust = DEFAULT_ADJUST.booleanValue();
  19.  
  20.   private int retryTimes = 2;
  21.   private int dscount = 2;
  22.   private int innerStep = 1000;
  23.   private int outStep = 1000;
  24.   private String tableName = "sequence";
  25.   private String nameColumnName = "name";
  26.   private String valueColumnName = "value";
  27.   private String gmtModifiedColumnName = "gmt_modified";
  28.   private volatile String selectSql;
  29.   private volatile String updateSql;
  30.   private volatile String insertSql;
  31.   private ConcurrentHashMap<Integer, AtomicInteger> excludedKeyCount = new ConcurrentHashMap(this.dscount);
  32.   private int maxSkipCount = 10000;
  33.   private boolean useSlowProtect = false;
  34.   private int protectMilliseconds = 50;
  35.   private ExecutorService exec = Executors.newFixedThreadPool(1);
  36.  
  37.   public void init()
  38.     throws SequenceException
  39.   {
  40.     if (StringUtils.isEmpty(this.appName)) {
  41.       SequenceException sequenceException = new SequenceException("appName is Null ");
  42.  
  43.       log.error("没有配置appName", sequenceException);
  44.       throw sequenceException;
  45.     }
  46.     if ((this.dbGroupKeys == null) || (this.dbGroupKeys.size() == 0)) {
  47.       log.error("没有配置dbgroupKeys");
  48.       throw new SequenceException("dbgroupKeys为空！");
  49.     }
  50.  
  51.     this.dataSourceMap = new HashMap();
  52.     for (String dbGroupKey : this.dbGroupKeys)
  53.       if (!dbGroupKey.toUpperCase().endsWith("-OFF"))
  54.       {
  55.         TGroupDataSource tGroupDataSource = new TGroupDataSource(dbGroupKey, this.appName);
  56.  
  57.         tGroupDataSource.init();
  58.         this.dataSourceMap.put(dbGroupKey, tGroupDataSource);
  59.       }
  60.     if (this.dbGroupKeys.size() >= this.dscount)
  61.       this.dscount = this.dbGroupKeys.size();
  62.     else {
  63.       for (int ii = this.dbGroupKeys.size(); ii < this.dscount; ii++) {
  64.         this.dbGroupKeys.add(new StringBuilder().append(this.dscount).append("-OFF").toString());
  65.       }
  66.     }
  67.     this.outStep = (this.innerStep * this.dscount);
  68.  
  69.     StringBuilder sb = new StringBuilder();
  70.     sb.append("GroupSequenceDao初始化完成：\r\n ");
  71.     sb.append("appName:").append(this.appName).append("\r\n");
  72.     sb.append("innerStep:").append(this.innerStep).append("\r\n");
  73.     sb.append("dataSource:").append(this.dscount).append("个:");
  74.     for (String str : this.dbGroupKeys) {
  75.       sb.append("[").append(str).append("]、");
  76.     }
  77.     sb.append("\r\n");
  78.     sb.append("adjust：").append(this.adjust).append("\r\n");
  79.     sb.append("retryTimes:").append(this.retryTimes).append("\r\n");
  80.     sb.append("tableName:").append(this.tableName).append("\r\n");
  81.     sb.append("nameColumnName:").append(this.nameColumnName).append("\r\n");
  82.     sb.append("valueColumnName:").append(this.valueColumnName).append("\r\n");
  83.     sb.append("gmtModifiedColumnName:").append(this.gmtModifiedColumnName).append("\r\n");
  84.  
  85.     log.info(sb.toString());
  86.   }
  87.  
  88.   private boolean check(int index, long value)
  89.   {
  90.     return value % this.outStep == index * this.innerStep;
  91.   }
  92.  
  93.   public void adjust(String name)
  94.     throws SequenceException, SQLException
  95.   {
  96.     Connection conn = null;
  97.     PreparedStatement stmt = null;
  98.     ResultSet rs = null;
  99.  
  100.     for (int i = 0; i < this.dbGroupKeys.size(); i++)
  101.       if (!((String)this.dbGroupKeys.get(i)).toUpperCase().endsWith("-OFF"))
  102.       {
  103.         TGroupDataSource tGroupDataSource = (TGroupDataSource)this.dataSourceMap.get(this.dbGroupKeys.get(i));
  104.         try
  105.         {
  106.           conn = tGroupDataSource.getConnection();
  107.           stmt = conn.prepareStatement(getSelectSql());
  108.           stmt.setString(1, name);
  109.           GroupDataSourceRouteHelper.executeByGroupDataSourceIndex(0);
  110.           rs = stmt.executeQuery();
  111.           int item = 0;
  112.           while (rs.next()) {
  113.             item++;
  114.             long val = rs.getLong(getValueColumnName());
  115.             if (!check(i, val))
  116.             {
  117.               if (isAdjust()) {
  118.                 adjustUpdate(i, val, name);
  119.               } else {
  120.                 log.error("数据库中配置的初值出错！请调整你的数据库，或者启动adjust开关");
  121.                 throw new SequenceException("数据库中配置的初值出错！请调整你的数据库，或者启动adjust开关");
  122.               }
  123.             }
  124.           }
  125.  
  126.           if (item == 0)
  127.           {
  128.             if (isAdjust()) {
  129.               adjustInsert(i, name);
  130.             } else {
  131.               log.error("数据库中未配置该sequence！请往数据库中插入sequence记录，或者启动adjust开关");
  132.               throw new SequenceException("数据库中未配置该sequence！请往数据库中插入sequence记录，或者启动adjust开关");
  133.             }
  134.           }
  135.         }
  136.         catch (SQLException e) {
  137.           log.error("初值校验和自适应过程中出错.", e);
  138.           throw e;
  139.         } finally {
  140.           closeResultSet(rs);
  141.           rs = null;
  142.           closeStatement(stmt);
  143.           stmt = null;
  144.           closeConnection(conn);
  145.           conn = null;
  146.         }
  147.       }
  148.   }
  149.  
  150.   private void adjustUpdate(int index, long value, String name)
  151.     throws SequenceException, SQLException
  152.   {
  153.     long newValue = value - value % this.outStep + this.outStep + index * this.innerStep;
  154.     TGroupDataSource tGroupDataSource = (TGroupDataSource)this.dataSourceMap.get(this.dbGroupKeys.get(index));
  155.  
  156.     Connection conn = null;
  157.     PreparedStatement stmt = null;
  158.     ResultSet rs = null;
  159.     try {
  160.       conn = tGroupDataSource.getConnection();
  161.       stmt = conn.prepareStatement(getUpdateSql());
  162.       stmt.setLong(1, newValue);
  163.       stmt.setTimestamp(2, new Timestamp(System.currentTimeMillis()));
  164.       stmt.setString(3, name);
  165.       stmt.setLong(4, value);
  166.       GroupDataSourceRouteHelper.executeByGroupDataSourceIndex(0);
  167.       int affectedRows = stmt.executeUpdate();
  168.       if (affectedRows == 0) {
  169.         throw new SequenceException(new StringBuilder().append("faild to auto adjust init value at  ").append(name).append(" update affectedRow =0").toString());
  170.       }
  171.  
  172.       log.info(new StringBuilder().append((String)this.dbGroupKeys.get(index)).append("更新初值成功!").append("sequence Name：").append(name).append("更新过程：").append(value).append("-->").append(newValue).toString());
  173.     }
  174.     catch (SQLException e) {
  175.       log.error(new StringBuilder().append("由于SQLException,更新初值自适应失败！dbGroupIndex:").append((String)this.dbGroupKeys.get(index)).append("，sequence Name：").append(name).append("更新过程：").append(value).append("-->").append(newValue).toString(), e);
  176.  
  177.       throw new SequenceException(new StringBuilder().append("由于SQLException,更新初值自适应失败！dbGroupIndex:").append((String)this.dbGroupKeys.get(index)).append("，sequence Name：").append(name).append("更新过程：").append(value).append("-->").append(newValue).toString(), e);
  178.     }
  179.     finally
  180.     {
  181.       closeStatement(stmt);
  182.       stmt = null;
  183.       closeConnection(conn);
  184.       conn = null;
  185.     }
  186.   }
  187.  
  188.   private void adjustInsert(int index, String name)
  189.     throws SequenceException, SQLException
  190.   {
  191.     TGroupDataSource tGroupDataSource = (TGroupDataSource)this.dataSourceMap.get(this.dbGroupKeys.get(index));
  192.  
  193.     long newValue = index * this.innerStep;
  194.     Connection conn = null;
  195.     PreparedStatement stmt = null;
  196.     ResultSet rs = null;
  197.     try {
  198.       conn = tGroupDataSource.getConnection();
  199.       stmt = conn.prepareStatement(getInsertSql());
  200.       stmt.setString(1, name);
  201.       stmt.setLong(2, newValue);
  202.       stmt.setTimestamp(3, new Timestamp(System.currentTimeMillis()));
  203.       GroupDataSourceRouteHelper.executeByGroupDataSourceIndex(0);
  204.       int affectedRows = stmt.executeUpdate();
  205.       if (affectedRows == 0) {
  206.         throw new SequenceException(new StringBuilder().append("faild to auto adjust init value at  ").append(name).append(" update affectedRow =0").toString());
  207.       }
  208.  
  209.       log.info(new StringBuilder().append((String)this.dbGroupKeys.get(index)).append("   name:").append(name).append("插入初值:").append(name).append("value:").append(newValue).toString());
  210.     }
  211.     catch (SQLException e)
  212.     {
  213.       log.error(new StringBuilder().append("由于SQLException,插入初值自适应失败！dbGroupIndex:").append((String)this.dbGroupKeys.get(index)).append("，sequence Name：").append(name).append("   value:").append(newValue).toString(), e);
  214.  
  215.       throw new SequenceException(new StringBuilder().append("由于SQLException,插入初值自适应失败！dbGroupIndex:").append((String)this.dbGroupKeys.get(index)).append("，sequence Name：").append(name).append("   value:").append(newValue).toString(), e);
  216.     }
  217.     finally
  218.     {
  219.       closeResultSet(rs);
  220.       rs = null;
  221.       closeStatement(stmt);
  222.       stmt = null;
  223.       closeConnection(conn);
  224.       conn = null;
  225.     }
  226.   }
  227.  
  228.   public SequenceRange nextRange(final String name)
  229.     throws SequenceException
  230.   {
  231.     if (name == null) {
  232.       log.error("序列名为空！");
  233.       throw new IllegalArgumentException("序列名称不能为空");
  234.     }
  235.  
  236.     Connection conn = null;
  237.     PreparedStatement stmt = null;
  238.     ResultSet rs = null;
  239.  
  240.     int[] randomIntSequence = RandomSequence.randomIntSequence(this.dscount);
  241.     for (int i = 0; i < this.retryTimes; i++) {
  242.       for (int j = 0; j < this.dscount; j++) {
  243.         boolean readSuccess = false;
  244.         boolean writeSuccess = false;
  245.         int index = randomIntSequence[j];
  246.         if (!((String)this.dbGroupKeys.get(index)).toUpperCase().endsWith("-OFF"))
  247.         {
  248.           if (this.excludedKeyCount.get(Integer.valueOf(index)) != null) {
  249.             if (((AtomicInteger)this.excludedKeyCount.get(Integer.valueOf(index))).incrementAndGet() > this.maxSkipCount) {
  250.               this.excludedKeyCount.remove(Integer.valueOf(index));
  251.               log.error(new StringBuilder().append(this.maxSkipCount).append("次数已过，index为").append(index).append("的数据源后续重新尝试取序列").toString());
  252.             }
  253.  
  254.           }
  255.           else
  256.           {
  257.             final TGroupDataSource tGroupDataSource = (TGroupDataSource)this.dataSourceMap.get(this.dbGroupKeys.get(index));
  258.             long oldValue;
  259.             long newValue;
  260.             try
  261.             {
  262.               long oldValue;
  263.               if ((!this.useSlowProtect) || (this.excludedKeyCount.size() >= this.dscount - 1)) {
  264.                 conn = tGroupDataSource.getConnection();
  265.                 stmt = conn.prepareStatement(getSelectSql());
  266.                 stmt.setString(1, name);
  267.                 GroupDataSourceRouteHelper.executeByGroupDataSourceIndex(0);
  268.                 rs = stmt.executeQuery();
  269.                 rs.next();
  270.                 oldValue = rs.getLong(1);
  271.               } else {
  272.                 FutureTask future = new FutureTask(new Callable()
  273.                 {
  274.                   public Long call() throws Exception
  275.                   {
  276.                     Connection fconn = null;
  277.                     PreparedStatement fstmt = null;
  278.                     ResultSet frs = null;
  279.                     try {
  280.                       fconn = tGroupDataSource.getConnection();
  281.                       fstmt = fconn.prepareStatement(GroupSequenceDao.this.getSelectSql());
  282.                       fstmt.setString(1, name);
  283.                       GroupDataSourceRouteHelper.executeByGroupDataSourceIndex(0);
  284.                       frs = fstmt.executeQuery();
  285.                       frs.next();
  286.                       return Long.valueOf(frs.getLong(1));
  287.                     } finally {
  288.                       GroupSequenceDao.closeResultSet(frs);
  289.                       frs = null;
  290.                       GroupSequenceDao.closeStatement(fstmt);
  291.                       fstmt = null;
  292.                       GroupSequenceDao.closeConnection(fconn);
  293.                       fconn = null;
  294.                     }
  295.                   }
  296.                 });
  297.                 try
  298.                 {
  299.                   this.exec.submit(future);
  300.                   oldValue = ((Long)future.get(this.protectMilliseconds, TimeUnit.MILLISECONDS)).longValue();
  301.                 } catch (InterruptedException e) {
  302.                   throw new SQLException("[SEQUENCE SLOW-PROTECTED MODE]:InterruptedException", e);
  303.                 } catch (ExecutionException e) {
  304.                   throw new SQLException("[SEQUENCE SLOW-PROTECTED MODE]:ExecutionException", e);
  305.                 } catch (TimeoutException e) {
  306.                   throw new SQLException(new StringBuilder().append("[SEQUENCE SLOW-PROTECTED MODE]:TimeoutException,当前设置超时时间为").append(this.protectMilliseconds).toString(), e);
  307.                 }
  308.               }
  309.  
  310.               if (oldValue < 0L) {
  311.                 StringBuilder message = new StringBuilder();
  312.                 message.append("Sequence value cannot be less than zero, value = ").append(oldValue);
  313.  
  314.                 message.append(", please check table ").append(getTableName());
  315.  
  316.                 log.info(message);
  317.  
  318.                 closeResultSet(rs);
  319.                 rs = null;
  320.                 closeStatement(stmt);
  321.                 stmt = null;
  322.                 closeConnection(conn);
  323.                 conn = null; continue;
  324.               }
  325.               if (oldValue > 9223372036754775807L) {
  326.                 StringBuilder message = new StringBuilder();
  327.                 message.append("Sequence value overflow, value = ").append(oldValue);
  328.  
  329.                 message.append(", please check table ").append(getTableName());
  330.  
  331.                 log.info(message);
  332.  
  333.                 closeResultSet(rs);
  334.                 rs = null;
  335.                 closeStatement(stmt);
  336.                 stmt = null;
  337.                 closeConnection(conn);
  338.                 conn = null; continue;
  339.               }
  340.               newValue = oldValue + this.outStep;
  341.               if (!check(index, newValue))
  342.               {
  343.                 if (isAdjust()) {
  344.                   newValue = newValue - newValue % this.outStep + this.outStep + index * this.innerStep;
  345.                 }
  346.                 else {
  347.                   SequenceException sequenceException = new SequenceException(new StringBuilder().append((String)this.dbGroupKeys.get(index)).append(":").append(name).append("的值得错误，覆盖到其他范围段了！请修改数据库，或者开启adjust开关！").toString());
  348.  
  349.                   log.error(new StringBuilder().append((String)this.dbGroupKeys.get(index)).append(":").append(name).append("的值得错误，覆盖到其他范围段了！请修改数据库，或者开启adjust开关！").toString(), sequenceException);
  350.  
  351.                   throw sequenceException;
  352.                 }
  353.  
  354.               }
  355.  
  356.               closeResultSet(rs);
  357.               rs = null;
  358.               closeStatement(stmt);
  359.               stmt = null;
  360.               closeConnection(conn);
  361.               conn = null;
  362.             }
  363.             catch (SQLException e)
  364.             {
  365.               log.error(new StringBuilder().append("取范围过程中--查询出错！").append((String)this.dbGroupKeys.get(index)).append(":").append(name).toString(), e);
  366.  
  367.               if (this.excludedKeyCount.size() < this.dscount - 1) {
  368.                 this.excludedKeyCount.put(Integer.valueOf(index), new AtomicInteger(0));
  369.                 log.error(new StringBuilder().append("暂时踢除index为").append(index).append("的数据源，").append(this.maxSkipCount).append("次后重新尝试").toString());
  370.               }
  371.             }
  372.             finally
  373.             {
  374.               closeResultSet(rs);
  375.               rs = null;
  376.               closeStatement(stmt);
  377.               stmt = null;
  378.               closeConnection(conn);
  379.               conn = null;
  380.             }
  381.  
  382.             try
  383.             {
  384.               conn = tGroupDataSource.getConnection();
  385.               stmt = conn.prepareStatement(getUpdateSql());
  386.               stmt.setLong(1, newValue);
  387.               stmt.setTimestamp(2, new Timestamp(System.currentTimeMillis()));
  388.  
  389.               stmt.setString(3, name);
  390.               stmt.setLong(4, oldValue);
  391.               GroupDataSourceRouteHelper.executeByGroupDataSourceIndex(0);
  392.               int affectedRows = stmt.executeUpdate();
  393.               if (affectedRows == 0)
  394.               {
  395.                 closeStatement(stmt);
  396.                 stmt = null;
  397.                 closeConnection(conn);
  398.                 conn = null;
  399.               }
  400.               else
  401.               {
  402.                 closeStatement(stmt);
  403.                 stmt = null;
  404.                 closeConnection(conn);
  405.                 conn = null;
  406.               }
  407.             }
  408.             catch (SQLException e)
  409.             {
  410.               log.error(new StringBuilder().append("取范围过程中--更新出错！").append((String)this.dbGroupKeys.get(index)).append(":").append(name).toString(), e);
  411.             }
  412.             finally
  413.             {
  414.               closeStatement(stmt);
  415.               stmt = null;
  416.               closeConnection(conn);
  417.               conn = null;
  418.             }
  419.           }
  420.         }
  421.  
  422.       }
  423.  
  424.       if (i == this.retryTimes - 2) {
  425.         this.excludedKeyCount.clear();
  426.       }
  427.     }
  428.     log.error(new StringBuilder().append("所有数据源都不可用！且重试").append(this.retryTimes).append("次后，仍然失败!").toString());
  429.     throw new SequenceException("All dataSource faild to get value!");
  430.   }
  431.  
  432.   private String getInsertSql() {
  433.     if (this.insertSql == null) {
  434.       synchronized (this) {
  435.         if (this.insertSql == null) {
  436.           StringBuilder buffer = new StringBuilder();
  437.           buffer.append("insert into ").append(getTableName()).append("(");
  438.  
  439.           buffer.append(getNameColumnName()).append(",");
  440.           buffer.append(getValueColumnName()).append(",");
  441.           buffer.append(getGmtModifiedColumnName()).append(") values(?,?,?);");
  442.  
  443.           this.insertSql = buffer.toString();
  444.         }
  445.       }
  446.     }
  447.     return this.insertSql;
  448.   }
  449.  
  450.   private String getSelectSql() {
  451.     if (this.selectSql == null) {
  452.       synchronized (this) {
  453.         if (this.selectSql == null) {
  454.           StringBuilder buffer = new StringBuilder();
  455.           buffer.append("select ").append(getValueColumnName());
  456.           buffer.append(" from ").append(getTableName());
  457.           buffer.append(" where ").append(getNameColumnName()).append(" = ?");
  458.  
  459.           this.selectSql = buffer.toString();
  460.         }
  461.       }
  462.     }
  463.  
  464.     return this.selectSql;
  465.   }
  466.  
  467.   private String getUpdateSql() {
  468.     if (this.updateSql == null) {
  469.       synchronized (this) {
  470.         if (this.updateSql == null) {
  471.           StringBuilder buffer = new StringBuilder();
  472.           buffer.append("update ").append(getTableName());
  473.           buffer.append(" set ").append(getValueColumnName()).append(" = ?, ");
  474.  
  475.           buffer.append(getGmtModifiedColumnName()).append(" = ? where ");
  476.  
  477.           buffer.append(getNameColumnName()).append(" = ? and ");
  478.           buffer.append(getValueColumnName()).append(" = ?");
  479.  
  480.           this.updateSql = buffer.toString();
  481.         }
  482.       }
  483.     }
  484.  
  485.     return this.updateSql;
  486.   }
  487.  
  488.   private static void closeResultSet(ResultSet rs) {
  489.     if (rs != null)
  490.       try {
  491.         rs.close();
  492.       } catch (SQLException e) {
  493.         log.debug("Could not close JDBC ResultSet", e);
  494.       } catch (Throwable e) {
  495.         log.debug("Unexpected exception on closing JDBC ResultSet", e);
  496.       }
  497.   }
  498.  
  499.   private static void closeStatement(Statement stmt)
  500.   {
  501.     if (stmt != null)
  502.       try {
  503.         stmt.close();
  504.       } catch (SQLException e) {
  505.         log.debug("Could not close JDBC Statement", e);
  506.       } catch (Throwable e) {
  507.         log.debug("Unexpected exception on closing JDBC Statement", e);
  508.       }
  509.   }
  510.  
  511.   private static void closeConnection(Connection conn)
  512.   {
  513.     if (conn != null)
  514.       try {
  515.         conn.close();
  516.       } catch (SQLException e) {
  517.         log.debug("Could not close JDBC Connection", e);
  518.       } catch (Throwable e) {
  519.         log.debug("Unexpected exception on closing JDBC Connection", e);
  520.       }
  521.   }
  522.

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