我正在运行 Tomcat 7.0.22,我编写了一个简单的 servlet,它连接到 SQL Anywhere 12.0 数据库。当我运行 servlet 时,我得到 java.lang.ClassCastException: org.apache.tomcat.dbcp.dbcp.BasicDataSource cannot be cast to org.apache.tomcat.jdbc.pool.DataSource。我的 ./META-INF/content.xml 文件如下所示:
<Context> <Resource name="jdbc/FUDB" auth="Container" type="javax.sql.DataSource" username="dba" password="sql" driverClassName="sybase.jdbc.sqlanywhere.IDriver" factory="org.apache.tomcat.jdbc.pool.DataSourceFactory"
url="jdbc:sqlanywhere:uid=dba;pwd=sql;eng=BTH476331A_FedUtilization;" accessToUnderlyingConnectionAllowed="true" maxActive="8" maxIdle="4" />
我的 webapp web.xml 看起来像这样:
<?xml version="1.0" encoding="ISO-8859-1"?> <web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0" metadata-complete="true"> <display-name>FedUtilization</display-name> <servlet> <servlet-name>Report1</servlet-name> <display-name>Report1</display-name> <servlet-class>com.sapgss.ps.servlet.Report1</servlet-class>
Report1 /Report1
SQL Anywhere 12.0.1 server jdbc3 jdbc/FUDB javax.sql.DataSource Container
servlet代码如下:
import java.io.*; import java.sql.*; import javax.servlet.*; import javax.servlet.http.*; import javax.naming.*; import org.apache.catalina.core.StandardContext.*; import org.apache.tomcat.jdbc.pool.*; import com.sapgss.ps.dbutil.*; import org.apache.tomcat.dbcp.dbcp.BasicDataSource; public class Report1 extends HttpServlet { public void doGet(HttpServletRequest request,
HttpServletResponse response) throws IOException, ServletException { try { response.setContentType("text/html"); PrintWriter out = response.getWriter(); out.println(""); out.println(""); out.println("Hello Elaine!"); out.println(""); out.println(""); out.println("
Hello Elaine!
");
// This is how to code access to the database in Java Context initCtx = new InitialContext(); Context envCtx = (Context) initCtx.lookup("java:comp/env"); DataSource ds = (DataSource) envCtx.lookup("jdbc/FUDB"); Connection conn = ds.getConnection(); . . .
} }
当我尝试在此行获取 DataSource 时发生错误:
DataSource ds = (DataSource) envCtx.lookup("jdbc/FUDB");
提前谢谢我正在拔头发。
最佳答案
就我而言,我只是忘记输入:
factory="org.apache.tomcat.jdbc.pool.DataSourceFactory"
在我的
/tomcat7/conf/context.xml
中。刚刚添加,一切正常。我的context.xml:
<Context>
<Resource name="jdbc/gestrel" auth="Container"
type="javax.sql.DataSource"
driverClassName="org.postgresql.Driver"
url="jdbc:postgresql://127.0.0.1:5432/g...."
username="postgres"
password="....." maxActive="20" maxIdle="10"
factory="org.apache.tomcat.jdbc.pool.DataSourceFactory"
maxWait="-1"/>
</Context>
关于tomcat7 - java.lang.ClassCastException : org. apache.tomcat.dbcp.dbcp.BasicDataSource 无法转换为 org.apache.tomcat.jdbc.pool.DataSource,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/7667008/