Shipping Invoice Example Code
The following triggers and test class make up the shipping invoice example application:
Calculate Trigger
trigger calculate on Item__c (after insert, after update, after delete) {
// Use a map because it doesn't allow duplicate values
Map<ID, Shipping_Invoice__C> updateMap = new Map<ID, Shipping_Invoice__C>();
// Set this integer to -1 if we are deleting
Integer subtract ;
// Populate the list of items based on trigger type
List<Item__c> itemList;
if(trigger.isInsert || trigger.isUpdate){
itemList = Trigger.new;
subtract = 1;
}
else if(trigger.isDelete)
{
// Note -- there is no trigger.new in delete
itemList = trigger.old;
subtract = -1;
}
// Access all the information we need in a single query
// rather than querying when we need it.
// This is a best practice for bulkifying requests
set<Id> AllItems = new set<id>();
for(item__c i :itemList){
// Assert numbers are not negative.
// None of the fields would make sense with a negative value
System.assert(i.quantity__c > 0, 'Quantity must be positive');
System.assert(i.weight__c >= 0, 'Weight must be non-negative');
System.assert(i.price__c >= 0, 'Price must be non-negative');
// If there is a duplicate Id, it won't get added to a set
AllItems.add(i.Shipping_Invoice__C);
}
// Accessing all shipping invoices associated with the items in the trigger
List<Shipping_Invoice__C> AllShippingInvoices = [SELECT Id, ShippingDiscount__c,
SubTotal__c, TotalWeight__c, Tax__c, GrandTotal__c
FROM Shipping_Invoice__C WHERE Id IN :AllItems];
// Take the list we just populated and put it into a Map.
// This will make it easier to look up a shipping invoice
// because you must iterate a list, but you can use lookup for a map,
Map<ID, Shipping_Invoice__C> SIMap = new Map<ID, Shipping_Invoice__C>();
for(Shipping_Invoice__C sc : AllShippingInvoices)
{
SIMap.put(sc.id, sc);
}
// Process the list of items
if(Trigger.isUpdate)
{
// Treat updates like a removal of the old item and addition of the
// revised item rather than figuring out the differences of each field
// and acting accordingly.
// Note updates have both trigger.new and trigger.old
for(Integer x = 0; x < Trigger.old.size(); x++)
{
Shipping_Invoice__C myOrder;
myOrder = SIMap.get(trigger.old[x].Shipping_Invoice__C);
// Decrement the previous value from the subtotal and weight.
myOrder.SubTotal__c -= (trigger.old[x].price__c *
trigger.old[x].quantity__c);
myOrder.TotalWeight__c -= (trigger.old[x].weight__c *
trigger.old[x].quantity__c);
// Increment the new subtotal and weight.
myOrder.SubTotal__c += (trigger.new[x].price__c *
trigger.new[x].quantity__c);
myOrder.TotalWeight__c += (trigger.new[x].weight__c *
trigger.new[x].quantity__c);
}
for(Shipping_Invoice__C myOrder : AllShippingInvoices)
{
// Set tax rate to 9.25% Please note, this is a simple example.
// Generally, you would never hard code values.
// Leveraging Custom Settings for tax rates is a best practice.
// See Custom Settings in the Apex Developer Guide
// for more information.
myOrder.Tax__c = myOrder.Subtotal__c * .0925;
// Reset the shipping discount
myOrder.ShippingDiscount__c = 0;
// Set shipping rate to 75 cents per pound.
// Generally, you would never hard code values.
// Leveraging Custom Settings for the shipping rate is a best practice.
// See Custom Settings in the Apex Developer Guide
// for more information.
myOrder.Shipping__c = (myOrder.totalWeight__c * .75);
myOrder.GrandTotal__c = myOrder.SubTotal__c + myOrder.tax__c +
myOrder.Shipping__c;
updateMap.put(myOrder.id, myOrder);
}
}
else
{
for(Item__c itemToProcess : itemList)
{
Shipping_Invoice__C myOrder;
// Look up the correct shipping invoice from the ones we got earlier
myOrder = SIMap.get(itemToProcess.Shipping_Invoice__C);
myOrder.SubTotal__c += (itemToProcess.price__c *
itemToProcess.quantity__c * subtract);
myOrder.TotalWeight__c += (itemToProcess.weight__c *
itemToProcess.quantity__c * subtract);
}
for(Shipping_Invoice__C myOrder : AllShippingInvoices)
{
// Set tax rate to 9.25% Please note, this is a simple example.
// Generally, you would never hard code values.
// Leveraging Custom Settings for tax rates is a best practice.
// See Custom Settings in the Apex Developer Guide
// for more information.
myOrder.Tax__c = myOrder.Subtotal__c * .0925;
// Reset shipping discount
myOrder.ShippingDiscount__c = 0;
// Set shipping rate to 75 cents per pound.
// Generally, you would never hard code values.
// Leveraging Custom Settings for the shipping rate is a best practice.
// See Custom Settings in the Apex Developer Guide
// for more information.
myOrder.Shipping__c = (myOrder.totalWeight__c * .75);
myOrder.GrandTotal__c = myOrder.SubTotal__c + myOrder.tax__c +
myOrder.Shipping__c;
updateMap.put(myOrder.id, myOrder);
}
}
// Only use one DML update at the end.
// This minimizes the number of DML requests generated from this trigger.
update updateMap.values();
}
ShippingDiscount Trigger
trigger ShippingDiscount on Shipping_Invoice__C (before update) {
// Free shipping on all orders greater than $100
for(Shipping_Invoice__C myShippingInvoice : Trigger.new)
{
if((myShippingInvoice.subtotal__c >= 100.00) &&
(myShippingInvoice.ShippingDiscount__c == 0))
{
myShippingInvoice.ShippingDiscount__c =
myShippingInvoice.Shipping__c * -1;
myShippingInvoice.GrandTotal__c += myShippingInvoice.ShippingDiscount__c;
}
}
}
Shipping Invoice Test
@IsTest
private class TestShippingInvoice{
// Test for inserting three items at once
public static testmethod void testBulkItemInsert(){
// Create the shipping invoice. It's a best practice to either use defaults
// or to explicitly set all values to zero so as to avoid having
// extraneous data in your test.
Shipping_Invoice__C order1 = new Shipping_Invoice__C(subtotal__c = 0,
totalweight__c = 0, grandtotal__c = 0,
ShippingDiscount__c = 0, Shipping__c = 0, tax__c = 0);
// Insert the order and populate with items
insert Order1;
List<Item__c> list1 = new List<Item__c>();
Item__c item1 = new Item__C(Price__c = 10, weight__c = 1, quantity__c = 1,
Shipping_Invoice__C = order1.id);
Item__c item2 = new Item__C(Price__c = 25, weight__c = 2, quantity__c = 1,
Shipping_Invoice__C = order1.id);
Item__c item3 = new Item__C(Price__c = 40, weight__c = 3, quantity__c = 1,
Shipping_Invoice__C = order1.id);
list1.add(item1);
list1.add(item2);
list1.add(item3);
insert list1;
// Retrieve the order, then do assertions
order1 = [SELECT id, subtotal__c, tax__c, shipping__c, totalweight__c,
grandtotal__c, shippingdiscount__c
FROM Shipping_Invoice__C
WHERE id = :order1.id];
System.assert(order1.subtotal__c == 75,
'Order subtotal was not $75, but was '+ order1.subtotal__c);
System.assert(order1.tax__c == 6.9375,
'Order tax was not $6.9375, but was ' + order1.tax__c);
System.assert(order1.shipping__c == 4.50,
'Order shipping was not $4.50, but was ' + order1.shipping__c);
System.assert(order1.totalweight__c == 6.00,
'Order weight was not 6 but was ' + order1.totalweight__c);
System.assert(order1.grandtotal__c == 86.4375,
'Order grand total was not $86.4375 but was '
+ order1.grandtotal__c);
System.assert(order1.shippingdiscount__c == 0,
'Order shipping discount was not $0 but was '
+ order1.shippingdiscount__c);
}
// Test for updating three items at once
public static testmethod void testBulkItemUpdate(){
// Create the shipping invoice. It's a best practice to either use defaults
// or to explicitly set all values to zero so as to avoid having
// extraneous data in your test.
Shipping_Invoice__C order1 = new Shipping_Invoice__C(subtotal__c = 0,
totalweight__c = 0, grandtotal__c = 0,
ShippingDiscount__c = 0, Shipping__c = 0, tax__c = 0);
// Insert the order and populate with items.
insert Order1;
List<Item__c> list1 = new List<Item__c>();
Item__c item1 = new Item__C(Price__c = 1, weight__c = 1, quantity__c = 1,
Shipping_Invoice__C = order1.id);
Item__c item2 = new Item__C(Price__c = 2, weight__c = 2, quantity__c = 1,
Shipping_Invoice__C = order1.id);
Item__c item3 = new Item__C(Price__c = 4, weight__c = 3, quantity__c = 1,
Shipping_Invoice__C = order1.id);
list1.add(item1);
list1.add(item2);
list1.add(item3);
insert list1;
// Update the prices on the 3 items
list1[0].price__c = 10;
list1[1].price__c = 25;
list1[2].price__c = 40;
update list1;
// Access the order and assert items updated
order1 = [SELECT id, subtotal__c, tax__c, shipping__c, totalweight__c,
grandtotal__c, shippingdiscount__c
FROM Shipping_Invoice__C
WHERE Id = :order1.Id];
System.assert(order1.subtotal__c == 75,
'Order subtotal was not $75, but was '+ order1.subtotal__c);
System.assert(order1.tax__c == 6.9375,
'Order tax was not $6.9375, but was ' + order1.tax__c);
System.assert(order1.shipping__c == 4.50,
'Order shipping was not $4.50, but was '
+ order1.shipping__c);
System.assert(order1.totalweight__c == 6.00,
'Order weight was not 6 but was ' + order1.totalweight__c);
System.assert(order1.grandtotal__c == 86.4375,
'Order grand total was not $86.4375 but was '
+ order1.grandtotal__c);
System.assert(order1.shippingdiscount__c == 0,
'Order shipping discount was not $0 but was '
+ order1.shippingdiscount__c);
}
// Test for deleting items
public static testmethod void testBulkItemDelete(){
// Create the shipping invoice. It's a best practice to either use defaults
// or to explicitly set all values to zero so as to avoid having
// extraneous data in your test.
Shipping_Invoice__C order1 = new Shipping_Invoice__C(subtotal__c = 0,
totalweight__c = 0, grandtotal__c = 0,
ShippingDiscount__c = 0, Shipping__c = 0, tax__c = 0);
// Insert the order and populate with items
insert Order1;
List<Item__c> list1 = new List<Item__c>();
Item__c item1 = new Item__C(Price__c = 10, weight__c = 1, quantity__c = 1,
Shipping_Invoice__C = order1.id);
Item__c item2 = new Item__C(Price__c = 25, weight__c = 2, quantity__c = 1,
Shipping_Invoice__C = order1.id);
Item__c item3 = new Item__C(Price__c = 40, weight__c = 3, quantity__c = 1,
Shipping_Invoice__C = order1.id);
Item__c itemA = new Item__C(Price__c = 1, weight__c = 3, quantity__c = 1,
Shipping_Invoice__C = order1.id);
Item__c itemB = new Item__C(Price__c = 1, weight__c = 3, quantity__c = 1,
Shipping_Invoice__C = order1.id);
Item__c itemC = new Item__C(Price__c = 1, weight__c = 3, quantity__c = 1,
Shipping_Invoice__C = order1.id);
Item__c itemD = new Item__C(Price__c = 1, weight__c = 3, quantity__c = 1,
Shipping_Invoice__C = order1.id);
list1.add(item1);
list1.add(item2);
list1.add(item3);
list1.add(itemA);
list1.add(itemB);
list1.add(itemC);
list1.add(itemD);
insert list1;
// Seven items are now in the shipping invoice.
// The following deletes four of them.
List<Item__c> list2 = new List<Item__c>();
list2.add(itemA);
list2.add(itemB);
list2.add(itemC);
list2.add(itemD);
delete list2;
// Retrieve the order and verify the deletion
order1 = [SELECT id, subtotal__c, tax__c, shipping__c, totalweight__c,
grandtotal__c, shippingdiscount__c
FROM Shipping_Invoice__C
WHERE Id = :order1.Id];
System.assert(order1.subtotal__c == 75,
'Order subtotal was not $75, but was '+ order1.subtotal__c);
System.assert(order1.tax__c == 6.9375,
'Order tax was not $6.9375, but was ' + order1.tax__c);
System.assert(order1.shipping__c == 4.50,
'Order shipping was not $4.50, but was ' + order1.shipping__c);
System.assert(order1.totalweight__c == 6.00,
'Order weight was not 6 but was ' + order1.totalweight__c);
System.assert(order1.grandtotal__c == 86.4375,
'Order grand total was not $86.4375 but was '
+ order1.grandtotal__c);
System.assert(order1.shippingdiscount__c == 0,
'Order shipping discount was not $0 but was '
+ order1.shippingdiscount__c);
}
// Testing free shipping
public static testmethod void testFreeShipping(){
// Create the shipping invoice. It's a best practice to either use defaults
// or to explicitly set all values to zero so as to avoid having
// extraneous data in your test.
Shipping_Invoice__C order1 = new Shipping_Invoice__C(subtotal__c = 0,
totalweight__c = 0, grandtotal__c = 0,
ShippingDiscount__c = 0, Shipping__c = 0, tax__c = 0);
// Insert the order and populate with items.
insert Order1;
List<Item__c> list1 = new List<Item__c>();
Item__c item1 = new Item__C(Price__c = 10, weight__c = 1,
quantity__c = 1, Shipping_Invoice__C = order1.id);
Item__c item2 = new Item__C(Price__c = 25, weight__c = 2,
quantity__c = 1, Shipping_Invoice__C = order1.id);
Item__c item3 = new Item__C(Price__c = 40, weight__c = 3,
quantity__c = 1, Shipping_Invoice__C = order1.id);
list1.add(item1);
list1.add(item2);
list1.add(item3);
insert list1;
// Retrieve the order and verify free shipping not applicable
order1 = [SELECT id, subtotal__c, tax__c, shipping__c, totalweight__c,
grandtotal__c, shippingdiscount__c
FROM Shipping_Invoice__C
WHERE Id = :order1.Id];
// Free shipping not available on $75 orders
System.assert(order1.subtotal__c == 75,
'Order subtotal was not $75, but was '+ order1.subtotal__c);
System.assert(order1.tax__c == 6.9375,
'Order tax was not $6.9375, but was ' + order1.tax__c);
System.assert(order1.shipping__c == 4.50,
'Order shipping was not $4.50, but was ' + order1.shipping__c);
System.assert(order1.totalweight__c == 6.00,
'Order weight was not 6 but was ' + order1.totalweight__c);
System.assert(order1.grandtotal__c == 86.4375,
'Order grand total was not $86.4375 but was '
+ order1.grandtotal__c);
System.assert(order1.shippingdiscount__c == 0,
'Order shipping discount was not $0 but was '
+ order1.shippingdiscount__c);
// Add items to increase subtotal
item1 = new Item__C(Price__c = 25, weight__c = 20, quantity__c = 1,
Shipping_Invoice__C = order1.id);
insert item1;
// Retrieve the order and verify free shipping is applicable
order1 = [SELECT id, subtotal__c, tax__c, shipping__c, totalweight__c,
grandtotal__c, shippingdiscount__c
FROM Shipping_Invoice__C
WHERE Id = :order1.Id];
// Order total is now at $100, so free shipping should be enabled
System.assert(order1.subtotal__c == 100,
'Order subtotal was not $100, but was '+ order1.subtotal__c);
System.assert(order1.tax__c == 9.25,
'Order tax was not $9.25, but was ' + order1.tax__c);
System.assert(order1.shipping__c == 19.50,
'Order shipping was not $19.50, but was '
+ order1.shipping__c);
System.assert(order1.totalweight__c == 26.00,
'Order weight was not 26 but was ' + order1.totalweight__c);
System.assert(order1.grandtotal__c == 109.25,
'Order grand total was not $86.4375 but was '
+ order1.grandtotal__c);
System.assert(order1.shippingdiscount__c == -19.50,
'Order shipping discount was not -$19.50 but was '
+ order1.shippingdiscount__c);
}
// Negative testing for inserting bad input
public static testmethod void testNegativeTests(){
// Create the shipping invoice. It's a best practice to either use defaults
// or to explicitly set all values to zero so as to avoid having
// extraneous data in your test.
Shipping_Invoice__C order1 = new Shipping_Invoice__C(subtotal__c = 0,
totalweight__c = 0, grandtotal__c = 0,
ShippingDiscount__c = 0, Shipping__c = 0, tax__c = 0);
// Insert the order and populate with items.
insert Order1;
Item__c item1 = new Item__C(Price__c = -10, weight__c = 1, quantity__c = 1,
Shipping_Invoice__C = order1.id);
Item__c item2 = new Item__C(Price__c = 25, weight__c = -2, quantity__c = 1,
Shipping_Invoice__C = order1.id);
Item__c item3 = new Item__C(Price__c = 40, weight__c = 3, quantity__c = -1,
Shipping_Invoice__C = order1.id);
Item__c item4 = new Item__C(Price__c = 40, weight__c = 3, quantity__c = 0,
Shipping_Invoice__C = order1.id);
try{
insert item1;
}
catch(Exception e)
{
system.assert(e.getMessage().contains('Price must be non-negative'),
'Price was negative but was not caught');
}
try{
insert item2;
}
catch(Exception e)
{
system.assert(e.getMessage().contains('Weight must be non-negative'),
'Weight was negative but was not caught');
}
try{
insert item3;
}
catch(Exception e)
{
system.assert(e.getMessage().contains('Quantity must be positive'),
'Quantity was negative but was not caught');
}
try{
insert item4;
}
catch(Exception e)
{
system.assert(e.getMessage().contains('Quantity must be positive'),
'Quantity was zero but was not caught');
}
}
}