关于Tomcat连接池建立连接异常问题!

2005-02-17 02:23:20 228 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

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1.通过http://localhost:8080/admin建立了一个名为aaa的JNDI的连接池;
2.在项目的web.xml上增加:
<resource-ref>
<res-ref-name>aaa</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
3.写了一个测试的JSP;
<%@ page import="java.sql.*"%>
<%@ page import="javax.sql.*"%>
<%@ page import="javax.naming.*"%>
<%
DataSource ds = null;
try{
InitialContext ctx=new InitialContext();
ds=(DataSource)ctx.lookup("java:comp/env/aaa");
System.out.println(ds);
Connection conn = ds.getConnection();
System.out.println(conn);
Statement stmt = conn.createStatement();
String strSql = " select * from tbTest";
ResultSet rs = stmt.executeQuery(strSql);
while(rs.next())
{
System.out.println(rs.getString(1));
}
}
catch(Exception ex){
ex.printStackTrace();
}
%>

出现异常:
org.apache.commons.dbcp.SQLNestedException: Cannot create JDBC driver of class '' for connect URL 'null'

看了别人的帖子:
换了一个Tomcat的版本 5.0.28,
还是会出先这个问题!

期待高手帮我看看!
不胜感激!!!

...全文

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epson1980

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切换为时间正序

epson1980 2005-02-18

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自己顶

epson1980 2005-02-17

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帮帮忙了，上面的文件都全的！
可是调试看看！

epson1980 2005-02-17

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我调了一天了，有高人会吗？

以梦为马 2005-02-17

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新春愉快！

java_augur 2005-02-17

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不同版本的tomcat配置文件形式是不同的。
强烈建议看相应版本文档。

Czh_cz 2005-02-17

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epson1980 2005-02-17

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我的配置文件： (已将aaa改成了jdbc/test,test为数据库名称)
server.xml:
<?xml version='1.0' encoding='utf-8'?>
<Server>
<Listener className="org.apache.catalina.mbeans.ServerLifecycleListener"/>
<Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener"/>
<GlobalNamingResources>
<Environment name="simpleValue" type="java.lang.Integer" value="30"/>
<Resource auth="Container" description="User database that can be updated and saved" name="UserDatabase" type="org.apache.catalina.UserDatabase"/>
<Resource name="jdbc/test" type="javax.sql.DataSource"/>
<ResourceParams name="UserDatabase">
<parameter>
<name>factory</name>
<value>org.apache.catalina.users.MemoryUserDatabaseFactory</value>
</parameter>
<parameter>
<name>pathname</name>
<value>conf/tomcat-users.xml</value>
</parameter>
</ResourceParams>
<ResourceParams name="jdbc/test">
<parameter>
<name>url</name>
<value>jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=test</value>
</parameter>
<parameter>
<name>password</name>
<value>sa</value>
</parameter>
<parameter>
<name>maxActive</name>
<value>4</value>
</parameter>
<parameter>
<name>maxWait</name>
<value>5000</value>
</parameter>
<parameter>
<name>driverClassName</name>
<value>com.microsoft.jdbc.sqlserver.SQLServerDriver</value>
</parameter>
<parameter>
<name>username</name>
<value>sa</value>
</parameter>
<parameter>
<name>maxIdle</name>
<value>2</value>
</parameter>
</ResourceParams>
</GlobalNamingResources>
<Service name="Catalina">
<Connector acceptCount="100" connectionTimeout="20000" disableUploadTimeout="true" port="8080" redirectPort="8443" maxSpareThreads="75" maxThreads="150" minSpareThreads="25">
</Connector>
<Connector port="8009" protocol="AJP/1.3" protocolHandlerClassName="org.apache.jk.server.JkCoyoteHandler" redirectPort="8443">
</Connector>
<Engine defaultHost="localhost" name="Catalina">
<Host appBase="webapps" name="localhost">
<Logger className="org.apache.catalina.logger.FileLogger" prefix="localhost_log." suffix=".txt" timestamp="true"/>
</Host>
<Logger className="org.apache.catalina.logger.FileLogger" prefix="catalina_log." suffix=".txt" timestamp="true"/>
<Realm className="org.apache.catalina.realm.UserDatabaseRealm"/>
</Engine>
</Service>
</Server>
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
web.xml:
<web-app>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>

<error-page>
<error-code>404</error-code>
<location>/error.jsp</location>
</error-page>
<resource-ref>
<res-ref-name>jdbc/test</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
</web-app>
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
test.jsp:
<%@ page import="java.sql.*"%>
<%@ page import="javax.sql.*"%>
<%@ page import="javax.naming.*"%>
<%
DataSource ds = null;
try{
InitialContext ctx=new InitialContext();
ds=(DataSource)ctx.lookup("java:comp/env/jdbc/test");
System.out.println(ds);
Connection conn = ds.getConnection();
System.out.println(conn);
Statement stmt = conn.createStatement();
String strSql = " select * from tbTest";
ResultSet rs = stmt.executeQuery(strSql);
while(rs.next()){
System.out.println(rs.getString(1));
}
}
catch(Exception ex){
ex.printStackTrace();
}
%>

以梦为马 2005-02-17

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新春愉快！

kingliangzf 2005-02-17

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根据名字去查找的时候没有找到，应该是ds=(DataSource)ctx.lookup("java:comp/env/aaa");这条语句出的问题，你看看你的配置文件的写法和语句中的一样不

java_augur 2005-02-17

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I did the following to get up and running with Tomcat 5.5.4:
(Note that javatest was the name of my webapp, and javatestDB was the name of my database)

1) Copied "mysql-connector-java-3.0.16-ga-bin.jar" to "%CATALINA_HOME%\common\lib" (though I could have instead copied it to the "WEB-INF\lib" directory for my webapp if I didn't plan to use the driver across multiple applications.)

2) Added the following to my Java class:

InitialContext ic = new InitialContext();
ds = (DataSource)ic.lookup("java:comp/env/jdbc/javatestDB");
con = ds.getConnection();

3) Added the following within the "web-app" node of "WEB-INF/web.xml" (placing it at an appropriate location based on the DTD for web.xml files):

<resource-ref>
<description>DB Connection</description>
<res-ref-name>jdbc/javatestDB</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>

4) Added a "Resource" node within the "Context" node in %CATALINA_HOME%\conf\Catalina\localhost\javatest.xml:

<?xml version='1.0' encoding='utf-8'?>
<Context docBase="C:/eclipse/workspace/javatest" path="/javatest" reloadable="true" workDir="C:\eclipse\workspace\javatest\work">
<Resource auth="Container" name="jdbc/javatestDB" type="javax.sql.DataSource" driverClassName="com.mysql.jdbc.Driver" password="dbPassword" maxIdle="2" maxWait="5000" username="dbUsername" url="jdbc:mysql://localhost:3306/javatestDB?autoReconnect=true" maxActive="4"/>
</Context>

5) Restarted Tomcat

java_augur 2005-02-17

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java_augur 2005-02-17

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Here's what I did:
1. added resource-ref entry to web.xml

<resource-ref>
<description>DataSource for HR app</description>
<res-ref-name>jdbc/hrDS</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>

2. deployed WAR file to Tomcat

3. inside <tomcat_install_dir>\conf\Catalina\localhost\<my_app_context>.xml, I made sure that I had the
resource

entry in the file, which should have been populated upon deployment of the WAR file to Tomcat:

<Resource auth="Container" description="DataSource for HR app" name="jdbc/hrDS" type="javax.sql.DataSource" />

4. inside <tomcat_install_dir>\conf\Catalina\localhost\<context>.xml, I populated the
ResourceParams

like so:

<ResourceParams name="jdbc/hrDS">
<parameter>
<name>factory</name>
<value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
</parameter>
<parameter>
<name>maxWait</name>
<value>5000</value>
</parameter>
<parameter>
<name>maxActive</name>
<value>4</value>
</parameter>
<parameter>
<name>password</name>
<value />
</parameter>
<parameter>
<name>url</name>
<value>jdbc:odbc:HRFORECAST</value>
</parameter>
<parameter>
<name>driverClassName</name>
<value>sun.jdbc.odbc.JdbcOdbcDriver</value>
</parameter>
<parameter>
<name>maxIdle</name>
<value>2</value>
</parameter>
<parameter>
<name>username</name>
<value />
</parameter>
</ResourceParams>

epson1980 2005-02-17

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有人知道吗？

epson1980 2005-02-17

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三个驱动程序在Tomcat的Common/lib下有了，在工程的web-inf/lib下也有了！

llshnshd 2005-02-17

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是不是没有驱动程序啊？

关于Tomcat连接池建立连接异常问题!

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