We have packed day planned for each of you. Your trip to Cloudstock London at ExCel London will be worth it! Whether you are new to the salesforce platform (Force.com, Database.com, Site.com, Heroku) or an experienced developer, you will have opportunity to attend technical sessions, watch technology demos, plug-in and code, schedule 1-on-1 code consultations, build a cloud app in the hack lab, meet the experts, learn about partner solutions, and grow your community developer circle.

Developer event details:

Developer Sessions
Come learn about architecture and development from product managers, evangelists and cloud partners as they present the latest features, demo them, and show you how to use them in your apps during these technical sessions. Don’t miss the chance to fire up your computer and get step-by-step instruction on implementing these technologies in hands-on training sessions. Space is limited, so arrive early to ensure your spot. Check out all the session details, here.

Technology Demos
The Cloudstock DevZone is the technology playground for developers. In the heart of the DevZone, learn about the latest technology and development on Force.com, Database.com, Site.com and Heroku. Cloudstock partners will also have technical staff on hand to discuss the best ways to solve your problems with their solutions. Evangelists, product managers and community gurus will all be in the mix and available to discuss new ideas and technologies as we build the social enterprise together.

Technology Topics
Want to get details on the latest platform technologies. Visit us at these technology stations to find out the latest news, get a rundown on feature releases, and have your questions answered by technical experts.

• Force.com
• Apex Code
• Visual Workflow
• Force.com Security
• Web Services API
• Force.com ISV Partners
• Mobile
• Heroku
• Database.com
• Site.com
• and more…

Developer Hack Lab
Once you understand all the latest offerings, learn by doing at the hands-on Hack Lab. Technical staffers will be available to assist guiding you through the technology to gain a deeper understanding.

Mini Hacks

After debuting a successful new format in San Francisco, we’re bringing it to London: Mini Hacks! Report to the Hack area, adjacent to the Developer Hack Lab, between noon and 17:30 to pick up one or more hack challenge cards with instructions to solve these challenges to garner honour and prizes. Challenges vary in difficulty and technological focus, and serve as a great introduction to a variety of cloud-based services. Technical staff will be onsite to assist in completion of these challenges. We’ll be giving away lots of schwag to participants. You will have a chance to win Amazon giftcards, Jamboxes, as well as Jay-Z & Kanye West “Watch the Throne ‘tour” concert VIP Box tickets for completing challenges. Bring your laptop and start coding!

1-on-1 Code Consultations
Need help architecting or coding your application? Get technical help building your application by reserving a private 1:1 consultation with a Force.com or Database.com expert. Drop by the Code Consultation Desk for availability. It is not too late to schedule your free 1-on-1 code consultation.

Technology Partners
We’ll also have leading cloud partner, including Amazon, DataSift, DocuSign, Pusher, Neo4j, Dell Boomi, DataScout, Informatica, Jitterbit, Quest Software and Skyvva.

Start you journey to Cloudstock London by registering now! See you all on May 22 at Excel London and do not forget to bring your laptop.

Today, I want to highlight an important new addition to Apex that is easy to miss when perusing the Summer ’12 release notes - the addition of ‘getName’ and ‘newInstance’ methods to the Type system class. These new methods now allow you to instantiate Apex classes at runtime with just the String name of the class. No longer do you have to specify the type of class you want instantiated at compile time (e.g. MyClass newObj = new MyClass();). You can instead do something like this:

Type t = Type.forName('MyClass');
MyClass newObj = (MyClass)t.newInstance();

Experienced Java developers will recognize this as the start of supporting Reflection in the Force.com platform. Though Apex does not fully support all the features typically associated with Reflection yet, the ‘Type.newInstance’ method is an important step in that direction. Lets take a specific use case and walk through the how and why of this new Apex feature.

Imagine that you’re an ISV partner that has created a Managed Package on the Force.com platform (for listing on the AppExchange) to validate US Zip Codes for all Contact records added or updated in a Salesforce Org. Let say that your default implementation of this zip code validation checks for a valid 10 character zip code (e.g. ’94105-1234′). Some of your package subscribers might however wish to customize the validation logic by for example checking for a 5 digit zip instead. Since subscribers are prevented from viewing the code included in a Managed Package (for protecting the ISV’s IP), its not simply a matter of modifying the Apex logic included in the package. The new Type methods offer an elegant solution by allowing subscribers to author their own zip code validation and then having your package dynamically detect and instantiate that ‘override’ at runtime. Lets walk through the package design.

The first piece of the puzzle is to define a simple interface that all zip code validation scripts need to implement.

global interface ValidateZipCode {

    boolean isValidUSZip(String zip);

}

Next, lets say that your package includes a ‘default’ implementation that checks for a 10 character zip code.

global class ValidateZipCodeDefaultImpl implements ValidateZipCode {
    ...
    global boolean isValidUSZip(String zip){
        //Check for a valid 10 character zip code
        //and return true or false as appropriate
    }
}

Now say that one of your package subscribers wishes to implement a different validation logic. All they have to do, is to author a different implementation class. Something like

global class ValidateZipCodeMyCustomImpl implements ValidateZipCode {
    ...
    global boolean isValidUSZip(String zip){
        //Check for a valid 5 digit zip code and return true or false as appropriate
    }
}

Now comes the fun part. In order to pick the appropriate zip code validator, I’ve implemented the classic Factory design pattern.

global class ZipCodeValidatorFactory {
    public static ValidateZipCode getValidatorInstance(){
        String defaultZipCodeValidationClass =
               ValidateZipCodeDefaultImpl.class.getName();
        String zipCodeValidationClass;

        Zip_Code_Custom_Impl__c settings =
               Zip_Code_Custom_Impl__c.getInstance('Zip Code Validation');

        if (settings != null && settings.Zip_Code_Validation_Class__c != null) {
            zipCodeValidationClass = settings.Zip_Code_Validation_Class__c;
        }
        else {
            zipCodeValidationClass = defaultZipCodeValidationClass;
        }

        Type t = Type.forName(zipCodeValidationClass);
        ValidateZipCode zipCodeValidator = (ValidateZipCode)t.newInstance();
        return zipCodeValidator;
    }
}

By default, this factory class returns the default zip code validator class (ValidateZipCodeDefaultImpl) included in my Managed Package. However, subscribers can specify an ‘override’ by populating a Custom Setting (Zip_Code_Custom_Impl__c) with the name of the Apex class that implements the ValidateZipCode interface per their specific requirements. In the example above, the subscriber would set this Custom Setting to ‘ValidateZipCodeMyCustomImpl’. In my Factory class above, I can dynamically instantiate the correct zip code validator by using the ‘newInstance’ method (line 18).

The final piece of the puzzle is how I use the above Factory class to validate Contact zip codes. Here is the trigger code for that.

trigger CheckZipCodeTrigger on Contact (before insert, before update) {

    ValidateZipCode zipCodeValidator = ZipCodeValidatorFactory.getValidatorInstance();

    for (Contact c: Trigger.new)
    {
        if (c.MailingPostalCode != null && !zipCodeValidator.isValidUSZip(c.MailingPostalCode))
        {
            c.addError('Invalid Zip Code');
        }
    }
}

Hopefully the example above has helped illustrate the power of the new Type methods in Summer ’12. If you have another interesting use case for ‘Type.newInstance’, please comment on the post and share it with the community.