當Tomcat遭遇JBDC Driver，出現 'Cannot create resource instance' ！

2019-11-18 19:08:03

字體：大中小

來源：轉載

供稿：網友

用Tomcat，最擔心的就是配置JNDI的DataSource的時候出現問題，隨著各大廠商發布自己的JDBC的實現，兼容性的問題也就越來也突出了...

一般我們都是用Tomcat自帶的DBCP來處理，配置如下：
<Resource name="jdbc/MyDS" auth="Container" type="javax.sql.DataSource" />
<ResourceParams name="jdbc/MyDS">
<parameter>
<name>driverClassName</name>
<value>Oracle.jdbc.driver.OracleDriver</value>
</parameter>
<parameter>
<name>driverName</name>
<value>jdbc:oracle:thin:@server:port:sid</value>
</parameter>
<parameter>
<name>user</name>
<value>########</value>
</parameter>
<parameter>
<name>passWord</name>
<value>########</value>
</parameter>
</ResourceParams>

Oracle JDBC Driver for JDK 1.4 or JDK 1.5
http://www.oracle.com/technology/software/tech/java/sqlj_jdbc/htdocs/jdbc_10201.html

不過這個寫法，如果在JBuilderX中，跑Tomcat 4.1，加上最新版的 Oracle JDBC Driver會存在問題，系統拋出的錯誤為：
javax.naming.NamingException: Cannot create resource instance
at org.apache.naming.factory.ResourceFactory.getObjectInstance(ResourceFactory.java:189)
at javax.naming.spi.NamingManager.getObjectInstance(NamingManager.java:301)
at org.apache.naming.NamingContext.lookup(NamingContext.java:834)
at org.apache.naming.NamingContext.lookup(NamingContext.java:181)
at org.apache.naming.NamingContext.lookup(NamingContext.java:822)
at org.apache.naming.NamingContext.lookup(NamingContext.java:181)
at org.apache.naming.NamingContext.lookup(NamingContext.java:822)
at org.apache.naming.NamingContext.lookup(NamingContext.java:181)
at org.apache.naming.NamingContext.lookup(NamingContext.java:822)
at org.apache.naming.NamingContext.lookup(NamingContext.java:194)
at org.apache.naming.SelectorContext.lookup(SelectorContext.java:183)
at javax.naming.InitialContext.lookup(InitialContext.java:347)

看來DBCP針對java.sql.DataSource相關的實現與ojdbc14.jar存在兼容性的問題，需要按照下面的寫法才能OK：
<Resource name="jdbc/MyDS" type="oracle.jdbc.pool.OracleConnectionCacheImpl"/>
<ResourceParams name="jdbc/MyDS">
<parameter>
<name>factory</name>
<value>oracle.jdbc.pool.OracleDataSourceFactory</value>
</parameter>
<parameter>
<name>driverClassName</name>
<value>oracle.jdbc.driver.OracleDriver</value>
</parameter>
<parameter>
<name>url</name>
<value>jdbc:oracle:thin:@server:port:sid</value>
</parameter>
<parameter>
<name>user</name>
<value>########</value>
</parameter>
<parameter>
<name>password</name>
<value>########</value>
</parameter>
</ResourceParams>

原來Oracle自己實現了DataSource的工廠類來管理DataSource的建立！
同樣發現微軟的SQL Server 2000 Driver for JDBC Service Pack 3也存在這個問題！
http://www.microsoft.com/downloads/details.aspx?familyid=07287b11-0502-461a-b138-2aa54bfdc03a&displaylang=en

需要如下配置：
<Resource name="jdbc/MyDS" auth="Container" type="com.microsoft.jdbcx.sqlserver.SQLServerDataSource"/>
<ResourceParams name="jdbc/MyDS">
<parameter>
    <name>factory</name>
    <value>com.microsoft.jdbcx.sqlserver.SQLServerDataSourceFactory</value>
</parameter>
<parameter>
    <name>driverClassName</name>
    <value>com.microsoft.jdbcx.sqlserver.SQLServerDataSource</value>
</parameter>
<parameter>
    <name>driverName</name>
    <value>SQLServer</value>
</parameter>
<parameter>
    <name>description</name>
    <value>My DataSource</value>
</parameter>
<parameter>
    <name>serverName</name>
    <value>########</value>
</parameter>
<parameter>
    <name>portNumber</name>
    <value>1433</value>
</parameter>
<parameter>
    <name>selectMethod</name>
    <value>cursor</value>
</parameter>
<parameter>
    <name>databaseName</name>
    <value>########</value>
</parameter>
<parameter>
    <name>user</name>
    <value>########</value>
</parameter>
<parameter>
    <name>password</name>
    <value>########</value>
</parameter>
<parameter>
    <name>loginTimeout</name>
    <value>3000</value>
</parameter>
</ResourceParams>