这个问题是由于我认为因为我正在使用 getClob(1) 而我的数据库是 mysql,所以 CachedRowSet 可能在用 mysql 实现时遇到问题...... :(。如果我使用 getClob,它会给出类型不匹配并且当我转换时它到 String 并使用它给出以下异常....
public CachedRowSet viewQuery(String query) throws SQLException, Exception {
//query = query;
//CachedRowSetImpl crs =
CachedRowSet crs = new CachedRowSetImpl();
try {
if (connection.isClosed()) {
setConnection();
}
System.out.println("Connection count 1 : " + connectionCount);
statement = connection.createStatement();
rs = statement.executeQuery(query);
crs.populate(rs);
crs = crs.createCopy();
closeConnection();
System.out.println("Connection count 2 : " + connectionCount);
} catch (Exception e) {
e.printStackTrace();
}
return crs;
}
例外 :
SEVERE: Servlet.service() for servlet jsp threw exception
java.sql.SQLException: Invalid cursor position
at com.sun.rowset.CachedRowSetImpl.next(Unknown Source)
at
org.apache.jsp.eTender.Buyer.TenderBidCre_jsp._jspService(TenderBidCre_jsp.java:1460)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388)
at
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
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.ApplicationDispatcher.invoke(ApplicationDispatcher.java:646)
at
org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:551)
at
org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:488)
at
org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:968)
at org.apache.jsp.EProc_jsp._jspService(EProc_jsp.java:532)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388)
at
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
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:127)
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:293)
at
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
at
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602)
at
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Unknown Source)