Newbie here (sorry folks!); and I'm trying to get a date passed to my controller.  I created a dummy object (dummyTable) containing a date field so that I could use the InputText on my visual force page for the date field.  I did this so that the date picker would work.

The date I think is now passing to the controller, but I keep getting this error:

System.NullPointerException: Attempt to de-reference a null object
Error is in expression '{!fetch}' in component <apex:commandButton> in page testtereport: Class.selectAllSOQLExampleController.fetch: line 31, column 1
Class.selectAllSOQLExampleController.fetch: line 31, column 1

If I change my query to hard-code a date, I don't get the error.

Can anyone help? 

Below is the Visual Force Page; and Controller:
 

<apex:page controller="selectAllSOQLExampleController" tabStyle="Account" docType="HTML-5.0">
    <apex:form >
        <apex:pageBlock >
            <apex:pageBlockButtons >
               
               <b>Start Date: </b><apex:inputfield value="{!dum.dateOne__c}"/>
               
                <apex:commandButton value="Fetch Time Entries" action="{!fetch}"/>
            </apex:pageBlockButtons>
            <apex:pageBlockSection columns="1" title="Dynamic SOQL Query" collapsible="True">
                <apex:outputText value="{!query}">
                </apex:outputText>
            </apex:pageBlockSection>
 
            <apex:pageBlockSection title="Billable Docket Report" columns="1" collapsible="False">Test
                <apex:pageBlockTable value="{!TEList}" var="tec">
                    <apex:column width="30" value="{!tec.Functional_Area__c}"/>
                    <apex:column width="20" value="{!tec.Standard_Activities__c}"/>
                    <apex:column value="{!tec.Activity_Other__c}"/>
                    <apex:column width="10" value="{!tec.Project__c}"/>
                    <apex:column width="10" value="{!tec.Contract__c}"/>
                    <apex:column width="10" value="{!tec.Monday__c}"/>
                    <apex:column width="10" value="{!tec.Tuesday__c}"/>
                    <apex:column width="10" value="{!tec.Wednesday__c}"/>
                    <apex:column width="10" value="{!tec.Thursday__c}"/>
                    <apex:column width="10" value="{!tec.Friday__c}"/>
                    <apex:column width="10" value="{!tec.subtotal__c}"/>
                </apex:pageBlockTable>
 
            </apex:pageBlockSection>
        </apex:pageBlock>
    </apex:form>
</apex:page>

and the controller:

You can see on in the Query String, that the commented out query is working (with the hard-coded date); but the one with the dum.dateOne__c is not working.

public class selectAllSOQLExampleController {

   
    public dummyTable__c dum{get;set;} 
    public String startdt{get;set;}
    public List<Time_Card_Entry__c> TEList{get;set;}
    public String query{get;set;}
    public String startDate{get;set;}

 
 
 //   public dummyTable__c dum() {
 //    if(dum == null) dum = new dummyTable__c();
 //   return dum;
 //   }
    
    public PageReference fetch(){
        String SobjectApiName = 'Time_Card_Entry__c';
        Map<String, Schema.SObjectType> schemaMap = Schema.getGlobalDescribe();
        Map<String, Schema.SObjectField> fieldMap = schemaMap.get(SobjectApiName).getDescribe().fields.getMap();
 
        String commaSepratedFields = '';
        for(String fieldName : fieldMap.keyset()){
            if(commaSepratedFields == null || commaSepratedFields == ''){
                commaSepratedFields = fieldName;
            }else{
                commaSepratedFields = commaSepratedFields + ', ' + fieldName;
            }
        }
 //       query = 'select ' + commaSepratedFields + ' from ' + SobjectApiName + ' Where Monday_Date__c >=' + '2015-01-14' + ' Limit 500';
        query = 'select ' + commaSepratedFields + ' from ' + SobjectApiName + ' Where Monday_Date__c >=' + dum.dateOne__c + ' Limit 500';
         
  
 
        TEList = Database.query(query);
 
        return null;
    }
}