Question

求助！严重: Servlet.service() for servlet jsp threw exception

小白一个~~望各位大神帮助！

严重: Servlet.service() for servlet jsp threw exception
org.apache.jasper.JasperException: Unable to compile class for JSP:

An error occurred at line: 11 in the generated java file
Only a type can be imported. com.mysql.jdbc.Connection resolves to a package

Stacktrace:
at org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:92)
at org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:330)
at org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:423)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:317)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:295)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:282)
at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:586)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:317)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
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)

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Answer 1

你引入com.mysql.jdbc.Connection 这个类, 但是程序没有找到对应的jar包.
这个应该是MySQL的驱动包, 你在tomcat/lib目下要放一个, 最好在工程的lib目录下也放一个.

然后再说一句, 也许你应该引入的类应该是这个接口 java.sql.Connection, 而不是对应的MySQL提供的实现类

Answer 2

别把什么东西都放在jsp里面写
像这个链接数据库的代码，应该写在Java类中（一般写在dao中）。

你的这个异常的原因，是因为在运行时，Tomcat jsp编译错误，是因为jar包的问题。
尝试把与数据库有关的操作，放在Java代码里面，然后让jsp去调用。这样，你在java编译的时候，就能发现问题。