50,532
社区成员
发帖
与我相关
我的任务
分享
// connect to MySQL
void connSQL() {
String url = "jdbc:mysql://localhost:3306/wenxujie?characterEncoding=UTF-8";
String username = "root";
String password = "root"; // 加载驱动程序以连接数据库
try {
Class.forName("org.gjt.mm.mysql.Driver" );
conn = DriverManager.getConnection(url,username,password);
}
//捕获加载驱动程序异常
catch ( ClassNotFoundException cnfex ) {
System.err.println(
"装载 JDBC/ODBC 驱动程序失败。" );
cnfex.printStackTrace();
}
//捕获连接数据库异常
catch ( SQLException sqlex ) {
System.err.println( "无法连接数据库" );
sqlex.printStackTrace();
}
装载 JDBC/ODBC 驱动程序失败。
java.lang.ClassNotFoundException: org.gjt.mm.mysql.Driver
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1387)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1233)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:169)
at com.usb.wenxujie.SqlOperate.connSQL(SqlOperate.java:20)
at com.usb.wenxujie.SqlJsp.process(SqlJsp.java:35)
at com.usb.wenxujie.SqlJsp.doPost(SqlJsp.java:23)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Thread.java:619)[/quote]
或者试试吧A类能用的那块代码拷贝到B类中,再执行B,看看能否执行。 // connect to MySQL
void connSQL() {
String url = "jdbc:mysql://localhost:3306/wenxujie?characterEncoding=UTF-8";
String username = "root";
String password = "root"; // 加载驱动程序以连接数据库
try {
Class.forName("org.gjt.mm.mysql.Driver" );
conn = DriverManager.getConnection(url,username,password);
}
//捕获加载驱动程序异常
catch ( ClassNotFoundException cnfex ) {
System.err.println(
"装载 JDBC/ODBC 驱动程序失败。" );
cnfex.printStackTrace();
}
//捕获连接数据库异常
catch ( SQLException sqlex ) {
System.err.println( "无法连接数据库" );
sqlex.printStackTrace();
}
装载 JDBC/ODBC 驱动程序失败。
java.lang.ClassNotFoundException: org.gjt.mm.mysql.Driver
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1387)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1233)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:169)
at com.usb.wenxujie.SqlOperate.connSQL(SqlOperate.java:20)
at com.usb.wenxujie.SqlJsp.process(SqlJsp.java:35)
at com.usb.wenxujie.SqlJsp.doPost(SqlJsp.java:23)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Thread.java:619)