0
我正在用REST + Mysql + Java製作一個小型項目。 休息電話工作正常。但是當我在休息函數中進行任何數據庫事務時，例如我想從數據庫中獲取一些其他值，然後給出[java.lang.ClassNotFoundException: com.mysql.jdbc.Driver]。當我通過類的obj調用相同的函數，然後它工作正常，但如果通過rest api調用調用失敗。當我對函數進行休息調用時，數據也是通過參數和參數傳入的，我可以在函數體中使用它，但無法執行數據庫事務。mysql連接在本地正常工作，但在調用rest函數調用時失敗[java]
我發現了一個相同的 question但其對ASP.net
我加入MySQL的罐子類路徑，以及在WEB-INF/lib目錄/文件夾
我的連接類：
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class conectionclass {
public static Connection getConnection(){
Connection conn = null ;
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/emps","root", "12345");
System.out.println("------------- Connection Succesful ----------------");
} catch (SQLException | ClassNotFoundException e) {
// TODO Auto-generated catch block
System.out.println("------------- Connection Fail ----------------");
e.printStackTrace();
}
return conn;
}
}
我的休息功能：
@POST
@Path("/postjson")
@Produces("application/json")
public Employee getJSONfromApp(HashMap p) {
return (new empdao()).getEmployee("test", "1234") ;
}
員工DAO類功能：
@Override
public Employee getEmployee(String employee, String pass) {
int count = 0 ;
Connection conn = Connectionclass.getConnection();
// System.out.println("Employee : "+employee+" Connection : "+conn);
if(employee!=null || employee != "")
{
String query = "select * from emps where username = '"+employee+"' && pass = '"+pass+"' ";
try {
Statement stmt = conn.createStatement() ;
System.out.println("Statement created.."+ stmt);
ResultSet a = stmt.executeQuery(query);
while(a.next()){
return (new Employee(a.getString(2) , a.getString(3)));
}
} catch (Exception e) {
// TODO Auto-generated catch block
System.out.println("Error in connection.....");
// e.printStackTrace();
} finally{
try {
conn.close();
} catch (Exception e) {
System.out.println("Error in closing connection.....");
// e.printStackTrace();
}
}
}
return null;
}
輸出時通過電話RestService：
------------- Connection Fail ----------------
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1305)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1157)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:259)
at com.app.App3.Connectionclass.getConnection(Connectionclass.java:13)
at com.app.App3.empdao.getEmployee(empdao.java:47)
at com.mkyong.rest.JSONService.getJSONfromApp(JSONService.java:90)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at org.jboss.resteasy.core.MethodInjectorImpl.invoke(MethodInjectorImpl.java:140)
at org.jboss.resteasy.core.ResourceMethod.invokeOnTarget(ResourceMethod.java:255)
at org.jboss.resteasy.core.ResourceMethod.invoke(ResourceMethod.java:220)
at org.jboss.resteasy.core.ResourceMethod.invoke(ResourceMethod.java:209)
at org.jboss.resteasy.core.SynchronousDispatcher.getResponse(SynchronousDispatcher.java:519)
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:496)
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:119)
at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:208)
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:55)
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:50)
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:219)
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:610)
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$AbstractConnectionHandler.process(AbstractProtocol.java:668)
at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:223)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1517)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1474)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:744)
Error in connection.....