Creating a custom encryption plug-in
To create a custom encryption plug-in, you need to extend the following extension point:
The interface IEncryptionHelper defines two methods, as shown in the following code:
public interface IEncryptionHelper
  public String encrypt( String string );
  public String decrypt( String string );
You need to implement these methods and program your encryption and decryption logic there.
To install the custom encryption plug-in, copy the plug-in to the product’s plugins folder, where the default plug-in resides. Change the isDefault property in plugin.xml to true. Change the isDefault properties of the rest of the encryption plug-ins to false.

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