java - JSF 无法显示表中的数据

Question

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已关闭 11 年前。

我有一个托管 bean，它从数据库表中获取两个值

import java.io.Serializable;
import javax.enterprise.context.SessionScoped;
// or import javax.faces.bean.SessionScoped;
import javax.inject.Named;
/* include SQL Packages */
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import javax.sql.DataSource;
import javax.annotation.Resource;
import javax.faces.context.FacesContext;
import javax.inject.Inject;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
// or import javax.faces.bean.ManagedBean;   

import org.glassfish.osgicdi.OSGiService;

@Named("DashboardController")
@SessionScoped
public class Dashboard implements Serializable {

    private String SessionTTL = null;
    private String MaxActiveUsers = null;
    private String stringone = null;
    private String stringtwo = null;
    private String SQL_Statement = null;
    private String Password;
    private String User;

    public Dashboard(){
    }

    /* Call the Oracle JDBC Connection driver */
    @Resource(name = "jdbc/Oracle")
    private DataSource ds;

    public String getSessionTTL() {
        return SessionTTL;
    }

    public void setSessionTTL(String SessionTTL) {
        this.SessionTTL = SessionTTL;
    }

    public String getMaxActiveUsers() {
        return MaxActiveUsers;
    }

    public void setMaxActiveUsers(String MaxActiveUsers) {
        this.MaxActiveUsers = MaxActiveUsers;
    }


    //connect to DB and get settings values
    public List<Dashboard> getDashboardList()throws SQLException{

        List<Dashboard> list = new ArrayList<Dashboard>();

        if(ds == null) {
                throw new SQLException("Can't get data source");
        }

        Connection conn = ds.getConnection(); 

        if(conn == null) {
                throw new SQLException("Can't get database connection");
        }

        PreparedStatement ps = conn.prepareStatement("SELECT * from GLOBALSETTINGS");

        try{
            //get data from database        
            ResultSet result = ps.executeQuery();
            while (result.next()){
                Dashboard cust = new Dashboard();
                cust.setSessionTTL(result.getString("SessionTTL"));
                cust.setMaxActiveUsers(result.getString("MaxActiveUsers"));
                list.add(cust);
            }
        }
        catch(Exception e1){
            // Log the exception.
        }
        finally{
            try{
                ps.close();
                conn.close();
            }
            catch(Exception e2){
                // Log the exception.
            }
        }
        return list; 
    }
}

这是必须显示值的 JSF 表的代码:

                    <h:dataTable id="books"
                             columnClasses="list-column-center,
                             list-column-right, list-column-center,
                             list-column-right" headerClass="list-header"
                             rowClasses="list-row" styleClass="list-
                             background" value="#{DashboardController.getDashboardList()}" var="store">   
                    <h:column>
                        <f:facet name="header">
                          <h:outputText  value="#{store.SessionTTL}"/>
                        </f:facet>
                         <h:outputText value="#{store.SessionTTL}"/>
                    </h:column>
                    <h:column>
                        <f:facet name="header">
                          <h:outputText  value="#{store.MaxActiveUsers}"/>
                        </f:facet>
                         <h:outputText value="#{store.MaxActiveUsers}"/>
                    </h:column>

                </h:dataTable> 

问题是当我尝试运行 JSF 页面时出现此错误:

javax.el.PropertyNotFoundException: /Settings.xhtml @82,69 value="#{store.SessionTTL}": The class 'com.DX_57.SM_57.Dashboard' does not have the property 'SessionTTL'.
    at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:111)
    at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194)
    at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:182)
    at javax.faces.component.UIOutput.getValue(UIOutput.java:169)
    at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getValue(HtmlBasicInputRenderer.java:205)
    at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.getCurrentValue(HtmlBasicRenderer.java:355)
    at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeEnd(HtmlBasicRenderer.java:164)
    at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875)
    at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeRecursive(HtmlBasicRenderer.java:312)
    at com.sun.faces.renderkit.html_basic.TableRenderer.renderRow(TableRenderer.java:384)
    at com.sun.faces.renderkit.html_basic.TableRenderer.encodeChildren(TableRenderer.java:161)
    at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845)
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1757)
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1760)
    at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:402)
    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:594)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1542)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:161)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:331)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
    at com.sun.enterprise.v3.services.impl.ContainerMapper$AdapterCallable.call(ContainerMapper.java:317)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:195)
    at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:849)
    at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:746)
    at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1045)
    at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:228)
    at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
    at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
    at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
    at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
    at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
    at java.lang.Thread.run(Thread.java:722)

我在某个地方出错了，但我找不到它。

Answer 1

尝试将 store.SessionTTL 替换为 store.sessionTTL。属性应以小写字符开头。