Main trigger

trigger AccountBeforeUpdate on Account (after insert, after Update)
{
//Get the RecordType Id
List<RecordType> rTypeList = new List<RecordType>();
map<Id,String> curUsMap = new Map<Id,String>();
map<Id,String> curUsNAMap = new Map<Id,String>();
set<Id> currentIds = new set<Id>();
set<Id> currentSoldTos = new Set<Id>();
SET<Id> oldOwnerIds = new set<Id>();
rTypeList = [SELECT ID FROM RECORDTYPE WHERE NAME='Sold-to' And SOBJECTTYPE = 'Account' limit 1];
List<AccountShare> oldShareList = new List<AccountShare>();

//CASE 1 Sold To Account associated with any National Account
List<Account> mainList = new List<Account>();

//If any Sold to created with National Account then
//create sharing rule
if(trigger.IsInsert) // When A new Sold to account is created with National Account
{
for(Account acNew:trigger.new)
{
if(rTypeList[0].Id == acNew.RecordTypeId && acNew.NationalAccount__C !=null )
{
mainList.add(acNew);

}
}
}

if(trigger.IsUpdate)
{

//If there is already any sharing rule then get the Combination of account record and sharing userId
oldShareList = [SELECT ACCOUNTID,USERORGROUPID FROM ACCOUNTSHARE WHERE ACCOUNTID IN:(TRIGGER.OLDMAP.KEYSET())];
if(!oldShareList.isEmpty())
{
for(ACCOUNTSHARE A:oldShareList)
{
curUsMap.put(A.ACCOUNTID,A.USERORGROUPID);
}
}



for(Account acOld:trigger.Old)
{
for(Account ac:trigger.new)
{
//DO FILTERATION
if(!rTypeList.isEmpty())
{
// If Account is Sold To and is associated with National Account then do Operation
System.Debug('Old Account:' + ' ' + acOld.NationalAccount__C);
if(rTypeList[0].Id == ac.RecordTypeId && ac.NationalAccount__C !=null )
{
if(acOld.NationalAccount__C !=ac.NationalAccount__C && acOld.NationalAccount__C !=null )
{
// FINALLY ADD FILTERED RECORD To Main Account List to create sharing rule for them
//to provide National Account Owner R/W Permission
mainList.add(ac);
}
else if(acOld.NationalAccount__C == null)
{
// FINALLY ADD FILTERED RECORD To Main Account List to create sharing rule for them
//to provide National Account Owner R/W Permission
mainList.add(ac);
}
}
}

}
}

//CASE 2 - OWNERSHIP FOR ONE NATIONAL ACCOUNT CHANGES TO ANOTHER OWNER

rTypeList.clear();
//Get the recorTypeId for "National Account" type of Account
//we would track the ownership change events for these accounts only
rTypeList = [SELECT ID FROM RECORDTYPE WHERE NAME='National Account' And SOBJECTTYPE = 'Account' limit 1];

//iterating Old National Account Ownership records
for(Account acNOld:trigger.Old)
{
System.Debug('New List:' + ' ' + trigger.new);
//iterating new National Account Ownership records
for(Account acNNew:trigger.New)
{

//If account is National Account
if(acNOld.RecordTypeId == rTypeList[0].Id && acNNew.RecordTypeId == rTypeList[0].Id)
{
//If current National Account Owner is different to Old National Account Owner
if(acNOld.OwnerId != acNNew.OwnerId)
{
//then prepare list of those accounts
currentIds.add(acNNew.Id);
oldOwnerIds.add(acNOld.OwnerId);
}
}
}
}

//Now get the List of all Sold To Accounts associated to the
List<Account> updateSoldToOwnerAcList = new List<Account>();

updateSoldToOwnerAcList = [SELECT ID,NATIONALACCOUNT__c FROM ACCOUNT WHERE NATIONALACCOUNT__c IN:(currentIds)];
if(!updateSoldToOwnerAcList.IsEmpty())
{
for(Account acOwnerChangedSoldTo:updateSoldToOwnerAcList)
{
mainList.add(acOwnerChangedSoldTo);
currentSoldTos.add(acOwnerChangedSoldTo.Id);
}
}

//Now get the List of Sold To Id shared with Old National Account Owner
oldShareList.clear();
curUsNaMap.clear();
//If there is already any sharing rule then get the Combination of account record and sharing userId
oldShareList = [SELECT ACCOUNTID,USERORGROUPID FROM ACCOUNTSHARE WHERE ACCOUNTID IN:(currentSoldTos)
AND USERORGROUPID IN:(oldOwnerIds) AND ISDELETED =FALSE];
if(!oldShareList.isEmpty())
{
for(ACCOUNTSHARE A:oldShareList)
{
curUsNaMap.put(A.ACCOUNTID,A.USERORGROUPID);
}
}
}
//Finally invoke method for sharing rule creaton / revokation
if(!mainList.IsEmpty() && !curUsMap.isEmpty())
{
AccountTriggerCls.doRemoveSharingRule(curUsMap,mainList); // Remove current sharing rule and create new sharing rule
}
else if(!mainList.IsEmpty() && !curUsNaMap.isEmpty())
{
AccountTriggerCls.doRemoveSharingRule(curUsNaMap,mainList); // Remove current sharing rule and create new sharing rule
}
else
{
AccountTriggerCls.doCreateSharingRule(mainList); // Create first time new sharing rule once any Sold To is associated to any National Account
}
}

Apex class based on trigger

public class AccountTriggerCls
{
//Region global variable

public static List<AccountShare> acShareList= new List<AccountShare>();
static Map<Id,String> nationalIds = new Map<Id,String>();
static Map<Id,String> mapOwnerIds = new Map<Id,String>();

//end
//Creating sharing rule for the National Account Owner
public static void doCreateSharingRule(List<Account> acMainList)
{
//We would get the Id for the record
//mention it for dynamic sharing rule
for(Account acMa:acMainList)
{
nationalIds.put(acMa.NATIONALACCOUNT__c,acMa.Id);

}

//Get the NationalAccountOwner Ids map
List<Account> acNat = new List<Account>();
acNat = [SELECT ID,OWNERID FROM ACCOUNT WHERE ID IN:(nationalIds.KeySet())];
if(!acNat.isEmpty())
{
for(Account acNational:acNat)
{
mapOwnerIds.put(acNational.Id,acNational.OwnerId);
}
}


for(Account ac:acMainList)
{
AccountShare aShare = new AccountShare();
aShare.AccountId=ac.id;
aShare.AccountAccessLevel= 'Edit';
// System.Debug('Owner Id:' + ' ' + ac.nationalAccount__r.OwnerId);
aShare.UserOrGroupId=mapOwnerIds.get(ac.NationalAccount__C);
aShare.OpportunityAccessLevel = 'Edit';

acShareList.add(aShare);

}
upsert acShareList;
}

//Creating sharing rule for the National Account Owner
public static void doCreateReverseSharingRule(List<Account> acMainList,Map<Id,String> OldIds)
{

for(String n:OldIds.values())
{
for(Account ac:acMainList)
{
AccountShare aShare = new AccountShare();
aShare.AccountId=ac.id;
aShare.AccountAccessLevel= 'Read';
// System.Debug('Owner Id:' + ' ' + ac.nationalAccount__r.OwnerId);
aShare.UserOrGroupId=n;
aShare.OpportunityAccessLevel = 'Read';

acShareList.add(aShare);

}
}
upsert acShareList;
}


//Removing sharing rule for Old Owner
public static void doRemoveSharingRule(Map<Id,String> oldIdMap,List<Account> acMainList)
{

List<AccountShare> oldShareList = new List<AccountShare>();
oldShareList = [SELECT ID,USERORGROUPID,AccountAccessLevel FROM ACCOUNTSHARE WHERE ACCOUNTID IN:(oldIdMap.keySet())
];
if(!oldShareList.isEmpty())
{
for(AccountShare acOls:oldShareList)
{
mapOwnerIds.put(acOls.USERORGROUPID,acOls.USERORGROUPID);
}
doCreateReverseSharingRule(acMainList,mapOwnerIds);
}
// finally create the sharing rule
doCreateSharingRule(acMainList);
}

//end

}

Test Class

@isTest
private class AccountTriggerCls_Test{

Static AccountTriggerCls mainClass=null;
Static Account accountObj;

Static testMethod void AccountTriggerCls_Test()
{
Test.StartTest();

PrepareTestData();

Test.StopTest();
}

static void PrepareTestData()
{
//Create User and attach National Account Manager profile

List<Profile> pList = new List<Profile>();

pList = [SELECT ID FROM PROFILE WHERE NAME='National Account Manager' Limit 1];
User u = new User(FirstName='Test',LastName='tt',username='ab@a.com',CommunityNickname='aa',
profileId=pList[0].Id,alias='ATE',email='a@a.com',TimeZoneSidKey='America/Los_Angeles',LocaleSidKey='en_US',
LanguageLocaleKey='en_US',EmailEncodingKey='UTF-8');
insert u;

//Create National Account and Assign Owner
Account acNa = (Account)DataCreator.creatObjectDataWithAllButNoRelationship('Account',1);
List<RecordType> rTypeList = new List<RecordType>();
rTypeList = [SELECT ID FROM RECORDTYPE WHERE NAME='National Account' Limit 1];
if(!rTypeList.IsEmpty())
{
acNa.RecordTypeId = rTypeList[0].Id;
acNa.OwnerId = u.Id;
acNa.National__c = true;
}
update acNa;

//Create Sold To Account
Account acSt = (Account)DataCreator.creatObjectDataWithAllButNoRelationship('Account',1);
List<RecordType> rTypeListSt = new List<RecordType>();
rTypeListSt = [SELECT ID FROM RECORDTYPE WHERE NAME='Sold-to' Limit 1 ];
if(!rTypeListSt.IsEmpty())
{

acSt.RecordTypeId = rTypeListSt[0].Id ;
acSt.NationalAccount__c= acNa.Id;
acSt.National__c = true;
}
update acSt;
}

}

I have used datacreator which is an accelarator class to cover the test class.

Please help me to solve the update problem.As   doCreateSharingRule(acMainList) in the rigger is not executing.

VF

<apex:page controller="addressfinderController" tabstyle="Location">

<apex:form >

<apex:pageBlock mode="edit">

<apex:pageMessages />

<apex:pageBlockSection >

<apex:inputField value="{!Location__c.Company__c}"/>

<apex:inputField value="{!Location__c.Location_Address__c}"/>

</apex:pageBlockSection>

<apex:pageBlockButtons location="bottom">

<apex:commandButton value="Save" action="{!save}"/>

</apex:pageBlockButtons>

</apex:pageBlock>

</apex:form>

</apex:page>

Controller

public class addressfinderController{

public Location__c location { get; private set; }

public addressfinderController() {

Id id = ApexPages.currentPage().getParameters().get('id');

location = (id == null) ? new Location__c() :

[SELECT Company__c,Location_Address__c FROM Location__c WHERE Id = :id];

}

public PageReference save() {

try {

upsert(location);

} catch(System.DMLException e) {

ApexPages.addMessages(e);

return null;

}

// After Save, navigate to the default view page:

return (new ApexPages.Controller(location)).view();

}

}

I have wrote some triggers in sandbox, but I don't know how to write test class for trigger?

This is one of my trigger, very simple,

trigger Accountchecking on Account (before insert) {
   if (Trigger.new[0].Name != NULL && Trigger.new[0].group__C != NULL && Trigger.new[0]. BillingCountry  != NULL)  {
       Account[] acc = [ select id from account WHERE name = :Trigger.new[0].Name and group__C=: trigger.new[0].group__C and  BillingCountry =:Trigger.new[0].BillingCountry];
       if (acc.size() > 0) {
           Trigger.new[0].Name.addError('Account Name ,Group and Country cannot be repeated!');
       }
   }
}

So, I should write one test class in apex, and then the trigger can be seen in org?

Great Thanks