上連接創建

Question

我在這段代碼中得到一個NullPointerException異常的SQLite NullPointerException異常錯誤更新21.我使用在GlassFish 4上運行的java2s.com的SQLite JDBC 3.7.2的編譯和源JAR（sqlite-jdbc-3.7.2.jar和sqlite-jdbc-3.7.2-sources.jar）。 1.1 build 1.你可以在GitHub上訪問我的代碼github.com/dhDZsG9QfQK3VTiF5KOs/California_Water_Data_Visualization。我在github.com/dhDZsG9QfQK3VTiF5KOs/California_Water_Data_Visualization/issues/1上爲此創建了一個GitHub問題。

堆棧跟蹤：

org.sqlite.NestedDB$CausedSQLException.fillInStackTrace(NestedDB.java:649) 
java.lang.Throwable.(Throwable.java:250) 
java.lang.Exception.(Exception.java:54) 
java.sql.SQLException.(SQLException.java:140) 
org.sqlite.NestedDB$CausedSQLException.(NestedDB.java:626) 
org.sqlite.NestedDB._open(NestedDB.java:63) 
org.sqlite.DB.open(DB.java:86) 
org.sqlite.Conn.open(Conn.java:140) 
org.sqlite.Conn.(Conn.java:57) 
org.sqlite.JDBC.createConnection(JDBC.java:77) 
org.sqlite.JDBC.connect(JDBC.java:64) 
java.sql.DriverManager.getConnection(DriverManager.java:579) 
java.sql.DriverManager.getConnection(DriverManager.java:243) 
com.solly.CaliforniaWaterDataVisualizationJSPCode.update(CaliforniaWaterDataVisualizationJSPCode.java:18) 
org.apache.jsp.update_jsp._jspService(update_jsp.java:53) 
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:790) 
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:411) 
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:473) 
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:377) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:790) 
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) 
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
java.lang.reflect.Method.invoke(Method.java:601) 
org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:323) 
org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:321) 
java.security.AccessController.doPrivileged(Native Method) 
javax.security.auth.Subject.doAsPrivileged(Subject.java:536) 
org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:356) 
org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:214) 
org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1676) 
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318) 
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160) 
org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734) 
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673) 
com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99) 
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174) 
org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:416) 
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:283) 
com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:459) 
com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:167) 
org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:206) 
org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:180) 
org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:235) 
org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119) 
org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:283) 
org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:200) 
org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:132) 
org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:111) 
org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77) 
org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:536) 
org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:112) 
org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117) 
org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:56) 
org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137) 
org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:591) 
org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:571) 
java.lang.Thread.run(Thread.java:722) 

Answer 1

我由try塊之前加入DriverManager.registerDriver(new JDBC());解決它。啓發我的是新錯誤信息（重新啓動服務器後）：「java.sql.SQLException：找不到適用於jdbc：sqlite：California_Water_Data.db的驅動程序」。