Camunda如何支持国产数据库达梦

前言

camunda流程引擎官方支持的数据库有&＃xff1a;MySQL 、MariaDB 、Oracle 、DB2 、PostgreSQL 、SQL Server、H2。对于其他类型的数据库如何支持&＃xff0c;尤其是国产数据库的支持&＃xff0c;下面以达梦数据库为例进行介绍。对于其他国产数据库如人大金仓、神州通用等也是同样的修改方法&＃xff0c;只是需要注意一下对应数据库的方言即可。

一、引入达梦数据库驱动包

在maven工程的Resources目录下建lib目录&＃xff0c;放入达梦数据库驱动包Dm7JdbcDriver17.jar&＃xff0c;并配置maven为本地引用

dm.jdbc.driver.DmDriver
jdbc
system
${project.basedir}/src/main/resources/lib/Dm7JdbcDriver17.jar

二、配置达梦数据源

url: jdbc:dm://127.0.0.1:5236
username: oa
password: 12345678aA
driver-class-name: dm.jdbc.driver.DmDriver

三、修改camunda代码&＃xff0c;支持达梦数据库

1. 修改ProcessEngineConfigurationImpl类的代码

在org.camunda.bpm.engine.impl.cfg.ProcessEngineConfigurationImpl类的getDefaultDatabaseTypeMappings方法里增加
databaseTypeMappings.setProperty(“DM DBMS”, “dm”);

protected static Properties getDefaultDatabaseTypeMappings() {
Properties databaseTypeMappings &＃61; new Properties();
databaseTypeMappings.setProperty("H2", "h2");
databaseTypeMappings.setProperty(MY_SQL_PRODUCT_NAME, "mysql");
databaseTypeMappings.setProperty(MARIA_DB_PRODUCT_NAME, "mariadb");
databaseTypeMappings.setProperty("Oracle", "oracle");
databaseTypeMappings.setProperty("PostgreSQL", "postgres");
databaseTypeMappings.setProperty("Microsoft SQL Server", "mssql");
databaseTypeMappings.setProperty("DB2", "db2");
databaseTypeMappings.setProperty("DB2", "db2");
databaseTypeMappings.setProperty("DB2/NT", "db2");
databaseTypeMappings.setProperty("DB2/NT64", "db2");
databaseTypeMappings.setProperty("DB2 UDP", "db2");
databaseTypeMappings.setProperty("DB2/LINUX", "db2");
databaseTypeMappings.setProperty("DB2/LINUX390", "db2");
databaseTypeMappings.setProperty("DB2/LINUXX8664", "db2");
databaseTypeMappings.setProperty("DB2/LINUXZ64", "db2");
databaseTypeMappings.setProperty("DB2/400 SQL", "db2");
databaseTypeMappings.setProperty("DB2/6000", "db2");
databaseTypeMappings.setProperty("DB2 UDB iSeries", "db2");
databaseTypeMappings.setProperty("DB2/AIX64", "db2");
databaseTypeMappings.setProperty("DB2/HPUX", "db2");
databaseTypeMappings.setProperty("DB2/HP64", "db2");
databaseTypeMappings.setProperty("DB2/SUN", "db2");
databaseTypeMappings.setProperty("DB2/SUN64", "db2");
databaseTypeMappings.setProperty("DB2/PTX", "db2");
databaseTypeMappings.setProperty("DB2/2", "db2");
databaseTypeMappings.setProperty("DM DBMS", "dm"); //达梦
return databaseTypeMappings;
}


2. 修改DbSqlSessionFactory类代码

org.camunda.bpm.engine.impl.db.sql.DbSqlSessionFactory类里增加对达梦数据库的语法解析。
public static final String DMDBMS &＃61; “dm”;//达梦数据库
public static final String[] SUPPORTED_DATABASES &＃61; {MSSQL, DB2, ORACLE, H2, MYSQL, POSTGRES, MARIADB, DMDBMS};

public class DbSqlSessionFactory implements SessionFactory {
public static final String MSSQL &＃61; "mssql";
public static final String DB2 &＃61; "db2";
public static final String ORACLE &＃61; "oracle";
public static final String H2 &＃61; "h2";
public static final String MYSQL &＃61; "mysql";
public static final String POSTGRES &＃61; "postgres";
public static final String MARIADB &＃61; "mariadb";
public static final String DMDBMS &＃61; "dm";//达梦数据库
public static final String[] SUPPORTED_DATABASES &＃61; {
MSSQL, DB2, ORACLE, H2, MYSQL, POSTGRES, MARIADB, DMDBMS};


并在static方法里增加&＃xff1a;

databaseSpecificLimitBeforeStatements.put(DMDBMS, "select * from ( select a.*, ROWNUM rnum from (");
optimizeDatabaseSpecificLimitBeforeWithoutOffsetStatements.put(DMDBMS, "select * from ( select a.*, ROWNUM rnum from (");
databaseSpecificLimitAfterStatements.put(DMDBMS, " ) a where ROWNUM <#{lastRow}) where rnum >&＃61; #{firstRow}");
optimizeDatabaseSpecificLimitAfterWithoutOffsetStatements.put(DMDBMS, " ) a where ROWNUM <&＃61; #{maxResults})");
databaseSpecificLimitBeforeWithoutOffsetStatements.put(DMDBMS, "");
databaseSpecificLimitAfterWithoutOffsetStatements.put(DMDBMS, "AND ROWNUM <&＃61; #{maxResults}");
databaseSpecificInnerLimitAfterStatements.put(DMDBMS, databaseSpecificLimitAfterStatements.get(DMDBMS));
databaseSpecificLimitBetweenStatements.put(DMDBMS, "");
databaseSpecificLimitBetweenFilterStatements.put(DMDBMS, "");
databaseSpecificOrderByStatements.put(DMDBMS, defaultOrderBy);
databaseSpecificLimitBeforeNativeQueryStatements.put(DMDBMS, "");
databaseSpecificDistinct.put(DMDBMS, "distinct");
databaseSpecificEscapeChar.put(DMDBMS, defaultEscapeChar);
databaseSpecificDummyTable.put(DMDBMS, "FROM DUAL");
databaseSpecificBitAnd1.put(DMDBMS, "BITAND(");
databaseSpecificBitAnd2.put(DMDBMS, ",");
databaseSpecificBitAnd3.put(DMDBMS, ")");
databaseSpecificDatepart1.put(DMDBMS, "to_number(to_char(");
databaseSpecificDatepart2.put(DMDBMS, ",");
databaseSpecificDatepart3.put(DMDBMS, "))");
databaseSpecificTrueConstant.put(DMDBMS, "1");
databaseSpecificFalseConstant.put(DMDBMS, "0");
databaseSpecificIfNull.put(DMDBMS, "NVL");
databaseSpecificDaysComparator.put(DMDBMS, "${date} <&＃61; #{currentTimestamp} - ${days}");
databaseSpecificCollationForCaseSensitivity.put(DMDBMS, "");
addDatabaseSpecificStatement(DMDBMS, "selectHistoricProcessInstanceDurationReport", "selectHistoricProcessInstanceDurationReport_oracle");
addDatabaseSpecificStatement(DMDBMS, "selectHistoricTaskInstanceDurationReport", "selectHistoricTaskInstanceDurationReport_oracle");
addDatabaseSpecificStatement(DMDBMS, "selectHistoricTaskInstanceCountByTaskNameReport", "selectHistoricTaskInstanceCountByTaskNameReport_oracle");
addDatabaseSpecificStatement(DMDBMS, "selectFilterByQueryCriteria", "selectFilterByQueryCriteria_oracleDb2");
addDatabaseSpecificStatement(DMDBMS, "selectHistoricProcessInstanceIdsForCleanup", "selectHistoricProcessInstanceIdsForCleanup_oracle");
addDatabaseSpecificStatement(DMDBMS, "selectHistoricDecisionInstanceIdsForCleanup", "selectHistoricDecisionInstanceIdsForCleanup_oracle");
addDatabaseSpecificStatement(DMDBMS, "selectHistoricCaseInstanceIdsForCleanup", "selectHistoricCaseInstanceIdsForCleanup_oracle");
addDatabaseSpecificStatement(DMDBMS, "selectHistoricBatchIdsForCleanup", "selectHistoricBatchIdsForCleanup_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteAttachmentsByRemovalTime", "deleteAttachmentsByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteCommentsByRemovalTime", "deleteCommentsByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteHistoricActivityInstancesByRemovalTime", "deleteHistoricActivityInstancesByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteHistoricDecisionInputInstancesByRemovalTime", "deleteHistoricDecisionInputInstancesByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteHistoricDecisionInstancesByRemovalTime", "deleteHistoricDecisionInstancesByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteHistoricDecisionOutputInstancesByRemovalTime", "deleteHistoricDecisionOutputInstancesByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteHistoricDetailsByRemovalTime", "deleteHistoricDetailsByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteExternalTaskLogByRemovalTime", "deleteExternalTaskLogByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteHistoricIdentityLinkLogByRemovalTime", "deleteHistoricIdentityLinkLogByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteHistoricIncidentsByRemovalTime", "deleteHistoricIncidentsByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteJobLogByRemovalTime", "deleteJobLogByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteHistoricProcessInstancesByRemovalTime", "deleteHistoricProcessInstancesByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteHistoricTaskInstancesByRemovalTime", "deleteHistoricTaskInstancesByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteHistoricVariableInstancesByRemovalTime", "deleteHistoricVariableInstancesByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteUserOperationLogByRemovalTime", "deleteUserOperationLogByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteByteArraysByRemovalTime", "deleteByteArraysByRemovalTime_oracle");
addDatabaseSpecificStatement(DMDBMS, "deleteHistoricBatchesByRemovalTime", "deleteHistoricBatchesByRemovalTime_oracle");
constants &＃61; new HashMap();
constants.put("constant.event", "cast(&＃39;event&＃39; as nvarchar2(255))");
constants.put("constant.op_message", "NEW_VALUE_ || &＃39;_|_&＃39; || PROPERTY_");
constants.put("constant_for_update", "for update");
constants.put("constant.datepart.quarter", "&＃39;Q&＃39;");
constants.put("constant.datepart.month", "&＃39;MM&＃39;");
constants.put("constant.datepart.minute", "&＃39;MI&＃39;");
constants.put("constant.null.startTime", "null START_TIME_");
constants.put("constant.varchar.cast", "&＃39;${key}&＃39;");
constants.put("constant.integer.cast", "NULL");
constants.put("constant.null.reporter", "NULL AS REPORTER_");
dbSpecificConstants.put(DMDBMS, constants);


四、修改数据库连接池

如果工程中使用的是阿里巴巴的druid连接池&＃xff0c;可能会报如下错误&＃xff1a;
Cause: java.lang.IllegalStateException: dbType not support : dm
需要把sql防火墙等功能关闭掉即解决该问题&＃xff1a;
spring.datasource.filters&＃61;stat,wall,log4j
把这个配置里的wall去掉。
技术支持&＃xff1a;http://www.yunchengxc.com。