ビルドパスにhsqldb.jarを含めました。今、私は接続を作成したいが、私はjdbcDriverが見つからなかったというエラーだけを得た。ここに私のコードです:jdbcDriveクラスが見つかりません
package jdbc;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
/**
* Dies Klasse liefert eine JDBC Connection zurück
* @author Christian
*
*/
public class JDBCConnector {
private Connection connection;
public JDBCConnector(String url, String user, String password){
try{
Class.forName("org.hsqldb.jdbcDriver");
connection = DriverManager.getConnection(url, user, password);
}catch (ClassNotFoundException e){
System.err.println("Der Datenbanktreiber konnte nicht geladen werden");
e.printStackTrace();
} catch (SQLException e) {
System.err.println("Beim Erstellen der Verbindung ist ein Feheler aufgetreten.\n"
+ "Bitte überprüfen Sie die URL, sowie Usernamen und Passwort");
}
}
public Connection getConnection() throws Exception{
if(connection != null){
return connection;
}else{
throw new Exception("Connection == null");
}
}
}
そして、彼女はあなたがlibraray参照してください。 とスタックトレースを:
Der Datenbanktreiber konnte nicht geladen werden
java.lang.ClassNotFoundException: org.hsqldb.jdbcDriver
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1333)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1167)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at jdbc.JDBCConnector.<init>(JDBCConnector.java:18)
at org.apache.jsp.server.jsp.Access_jsp._jspService(Access_jsp.java:125)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:438)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:396)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:340)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:217)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
Aug 23, 2016 4:47:22 PM org.apache.catalina.core.StandardWrapperValve invoke
SCHWERWIEGEND: Servlet.service() for servlet [jsp] in context with path [/Gefaehrdungsbeurteilung] threw exception [java.lang.IllegalStateException: Exception occurred when flushing data] with root cause
java.io.IOException: Stream closed
at org.apache.jasper.runtime.JspWriterImpl.ensureOpen(JspWriterImpl.java:200)
at org.apache.jasper.runtime.JspWriterImpl.flushBuffer(JspWriterImpl.java:105)
at org.apache.jasper.runtime.PageContextImpl.release(PageContextImpl.java:184)
at org.apache.jasper.runtime.JspFactoryImpl.internalReleasePageContext(JspFactoryImpl.java:120)
at org.apache.jasper.runtime.JspFactoryImpl.releasePageContext(JspFactoryImpl.java:75)
at org.apache.jsp.server.jsp.Access_jsp._jspService(Access_jsp.java:148)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:438)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:396)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:340)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:217)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
EDIT: たぶんそれは、私がSAPUI5のPROJEKTを作成したことを、知っているimprotantだけど私はそれが重要ではないと思う。
私はorg.hsqldb.jdbc.JDBCDriverにクラス名を変更したのだが、どちらか動作しません。..私はJavaの初心者ではありませんが、これはこのエラーが発生した初めてのことですが、Eclipseを初めて使用しています。 – Chris
Java、Eclipse、JDBCなど、あまり知られていないことが多すぎます。エラーメッセージが表示されない場合は、問題の内容を確認できません。 – duffymo
上記はスタックトレース/エラーメッセージ – Chris