任何人都可以解释如何运行 activiti-rest.war 的过程，我正在使用 postgres 数据库。我在运行时将war文件复制到tomcat webapps中显示此错误，还有一件事我没有使用spring框架，我使用postgres配置更改db.properties文件，仍然配置设置的内容和位置。在tomcat中清楚地解释和老板
org.activiti.engine.ProcessEngines initProcessEnginFromResource
SEVERE: Exception while initializing process engine :couldn't check if tables are already present using metadata:
### Error getting a new connection. Cause: java.sql.SQLException: No suitable driver found for jdbc:postgresql://localhost:5432/activiti
### Cause: java.sql.SQLException: No suitable driver found for jdbc:postgresql://localhost:5432/activiti
org.activiti.engine.ActivitiException: couldn't check if tables are already present using metadata:
### Error getting a new connection. Cause: java.sql.SQLException: No suitable driver found for jdbc:postgresql://localhost:5432/activiti
### Cause: java.sql.SQLException: No suitable driver found for jdbc:postgresql://localhost:5432/activiti
at org.activiti.engine.impl.db.DbSqlSession.isTablePresent(DbSqlSession.java:890)
at org.activiti.engine.impl.db.DbSqlSession.isEngineTablePresent(DbSqlSession.java:854)
at org.activiti.engine.impl.db.DbSqlSession.dbSchemaUpdate(DbSqlSession.java:806)
at org.activiti.engine.impl.db.DbSqlSession.performSchemaOperationsProcessEngineBuild(DbSqlSession.java:1100)
at org.activiti.engine.impl.SchemaOperationsProcessEngineBuild.execute(SchemaOperationsProcessEngineBuild.java:25)
at org.activiti.engine.impl.interceptor.CommandExecutorImpl.execute(CommandExecutorImpl.java:24)
at org.activiti.engine.impl.interceptor.CommandContextInterceptor.execute(CommandContextInterceptor.java:60)
at org.activiti.engine.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:32)
at org.activiti.engine.impl.ProcessEngineImpl.<init>(ProcessEngineImpl.java:75)
at org.activiti.engine.impl.cfg.ProcessEngineConfigurationImpl.buildProcessEngine(ProcessEngineConfigurationImpl.java:311)
at org.activiti.engine.ProcessEngines.buildProcessEngine(ProcessEngines.java:194)
at org.activiti.engine.ProcessEngines.initProcessEnginFromResource(ProcessEngines.java:167)
at org.activiti.engine.ProcessEngines.init(ProcessEngines.java:98)
at org.activiti.engine.ProcessEngines.getProcessEngine(ProcessEngines.java:224)
at org.activiti.engine.ProcessEngines.getDefaultProcessEngine(ProcessEngines.java:217)
at org.activiti.rest.servlet.ActivitiServletContextListener.contextInitialized(ActivitiServletContextListener.java:39)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4791)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5285)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633)
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:977)
at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1655)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
Caused by: org.apache.ibatis.exceptions.PersistenceException:
### Error getting a new connection. Cause: java.sql.SQLException: No suitable driver found for jdbc:postgresql://localhost:5432/activiti
### Cause: java.sql.SQLException: No suitable driver found for jdbc:postgresql://localhost:5432/activiti
at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:23)
at org.apache.ibatis.session.defaults.DefaultSqlSession.getConnection(DefaultSqlSession.java:222)
at org.activiti.engine.impl.db.DbSqlSession.isTablePresent(DbSqlSession.java:867)
... 29 more
Caused by: java.sql.SQLException: No suitable driver found for jdbc:postgresql://localhost:5432/activiti
at java.sql.DriverManager.getConnection(DriverManager.java:602)
at java.sql.DriverManager.getConnection(DriverManager.java:154)
at org.apache.ibatis.datasource.unpooled.UnpooledDataSource.doGetConnection(UnpooledDataSource.java:181)
at org.apache.ibatis.datasource.unpooled.UnpooledDataSource.doGetConnection(UnpooledDataSource.java:176)
at org.apache.ibatis.datasource.unpooled.UnpooledDataSource.getConnection(UnpooledDataSource.java:80)
at org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:371)
at org.apache.ibatis.datasource.pooled.PooledDataSource.getConnection(PooledDataSource.java:80)
at org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:131)
at org.apache.ibatis.transaction.jdbc.JdbcTransaction.getConnection(JdbcTransaction.java:58)
at org.apache.ibatis.session.defaults.DefaultSqlSession.getConnection(DefaultSqlSession.java:220)
... 30 more