So here's my problem in short : I am trying to create a JSF page and a Java class to connect to a DB (postgres). The goal is to extract a result from the DB and then show it on the JSF, pretty simple right ?
My code is the following :
The JSF is :
<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:c="http://java.sun.com/jsp/jstl/core">
<h:head>
<title>Facelet Title</title>
</h:head>
<h:body>
Hello from Facelets
<p>${calendar.form}</p>
</h:body>
</html>
As for Java :
import java.sql.*;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.RequestScoped;
import javax.faces.bean.ViewScoped;
@ManagedBean(name="calendar")
@ViewScoped
@RequestScoped
public class Calendar {
private String form = null;
public String getForm() {
return form;
}
public void setForm(String form) {
this.form = form;
}
public Calendar(){
/* Connexion à la base de données */
String url = "jdbc:postgres://localhost:5432/postgres";
String utilisateur = "postgres";
String motDePasse = "123456789";
Connection connexion = null;
try {
connexion = DriverManager.getConnection( url, utilisateur, motDePasse );
/* Ici, nous placerons nos requêtes vers la BDD */
/* ... */
/* Création de l'objet gérant les requêtes */
Statement statement = connexion.createStatement();
/* Exécution d'une requête de lecture */
ResultSet resultat = statement.executeQuery( "SELECT * FROM detaillant WHERE date= \"2013-04-25\" ;" );
resultat.next();
setForm(resultat.getString( "form" ));
/* Traiter ici les valeurs récupérées. */
} catch ( SQLException e ) {
/* Gérer les éventuelles erreurs ici */
} finally {
if ( connexion != null )
try {
/* Fermeture de la connexion */
connexion.close();
} catch ( SQLException ignore ) {
/* Si une erreur survient lors de la fermeture, il suffit de l'ignorer. */
}
}
}//END of constructor
}
In my web.xml I have made sure to launch my app from the JSF page (which in my case was named index) as follows :
<welcome-file-list>
<welcome-file>faces/index.xhtml</welcome-file>
</welcome-file-list>
So, I thought I had it until I run the whole thing just to be bumped into one little problem : the page appears, still I don't get any value !
So, any idea about what I might change to have it working ? Thanks in advance !
Edit :
The stacktrace contained as a result the following :
com.sun.faces.mgbean.ManagedBeanCreationException: Impossible dinstancier la classe Calendar.
at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:193)
at com.sun.faces.mgbean.BeanBuilder.build(BeanBuilder.java:102)
at com.sun.faces.mgbean.BeanManager.createAndPush(BeanManager.java:409)
at com.sun.faces.mgbean.BeanManager.create(BeanManager.java:269)
at com.sun.faces.el.ManagedBeanELResolver.resolveBean(ManagedBeanELResolver.java:244)
at com.sun.faces.el.ManagedBeanELResolver.getValue(ManagedBeanELResolver.java:116)
at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176)
at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203)
at org.apache.el.parser.AstIdentifier.getValue(AstIdentifier.java:71)
at org.apache.el.parser.AstValue.getValue(AstValue.java:147)
at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:189)
at com.sun.faces.facelets.el.ELText$ELTextVariable.writeText(ELText.java:224)
at com.sun.faces.facelets.compiler.TextInstruction.write(TextInstruction.java:85)
at com.sun.faces.facelets.compiler.UIInstructions.encodeBegin(UIInstructions.java:82)
at com.sun.faces.facelets.compiler.UILeaf.encodeAll(UILeaf.java:183)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759)
at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:401)
at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:131)
at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:410)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:393)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:224)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:964)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:304)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:722)
Caused by: javax.faces.FacesException: java.sql.SQLException: No suitable driver found for jdbc:postgres://localhost:5432/postgres
at Calendar.<init>(Calendar.java:48)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
at java.lang.Class.newInstance0(Class.java:374)
at java.lang.Class.newInstance(Class.java:327)
at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:188)
... 41 more
Caused by: java.sql.SQLException: No suitable driver found for jdbc:postgres://localhost:5432/postgres
at java.sql.DriverManager.getConnection(DriverManager.java:604)
at java.sql.DriverManager.getConnection(DriverManager.java:221)
at Calendar.<init>(Calendar.java:27)
... 48 more
For a beginer, this is one hot served plate haha...
This is the main problem: SQLException: No suitable driver found. Looks like you forgot to load the driver. Since you're in learning phase, you can do this using Class.forName(<driver class name>);. Based on PostreSQL documentation about loading the driver:
String url = "jdbc:postgres://localhost:5432/postgres";
String utilisateur = "postgres";
String motDePasse = "123456789";
Connection connexion = null;
try {
Class.forName("org.postgresql.Driver");
connexion = DriverManager.getConnection( url, utilisateur, motDePasse );
//rest of code...
} catch (SQLException e) {
//this is a basic way to handle errors...
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
//...
In real world apps, you will use a database connection pool that is managed by the application server (Tomcat, Jboss, etc).