Group items tagged

AnemicDomainModel

Eric Evans

basic symptom of an Anemic Domain Model

Hello World, revisited with EJB3

history is persisted in the database by means of a JPA entity bean and those objects are serialized back to the Flex client each time you enter a new name.

Lazy Loading with Flex, BlazeDS and Hibernate

By using dpHibernate and lazy loading, none of this extra work is required

proxies are sent initially for collections and complex objects, and fetched on-demand when requested by the client

GraniteDS provides out-of-the-box integration with CDI via the Tide API

Integration with CDI

fully supports serialization of JPA entities from and to your Flex application, taking care of lazily loaded associations

Client Options

client there are two main choices

an ontology formally represents knowledge as a set of concepts within a domain, and the relationships between those concepts. It can be used to reason about the entities within that domain and may be used to describe the domain

n ontology renders shared vocabulary and taxonomy which models a domain with the definition of objects and/or concepts and their properties and relations

Common components of ontologies include:

CDI, JPA2 and JSF2

Apache Shiro

JpaRealm

Interface Realm

AuthenticatingRealm

AuthorizingRealm

Java EJB 3.0 UML Profile

[UML Profile for Java and EJB. Version 1.0]

Java 1.3, EJB 1.1 and most likely UML 1.4, so it could be only of some interest

Result Set Mapping

When a native SQL query returns objects, the SQL must ensure it returns the correct data to build the resultClass using the correct column names as specified in the mappings. If the SQL is more complex and returns different column names, or returns data for multiple objects then a @SqlResultSetMapping must be used.

@NamedNativeQuery

[For Greenfields]

Try to identify concepts and abstractions from the target domain. Use them as candidates for entities.

Do not obfuscate them with additional technical naming conventions like XYZEntity or "BOs".

Mapping enum to database column using JPA/Hibernate You can use any of the 3 approaches discussed above. Map the enum to an integer column. The persistence implementation should automatically convert enum to ordinal() and back for you. Map the enum to a String column. The persistence implementation should automatically convert the enum value to String value via the name() function. Map the enum using a business value. You should mark the enum field as @Transient, and create another String field which you can map to a String column in your database table. Here’s an example code snippet. view plaincopy to clipboardprint?@Entity  public class Product {   @Column   private String colorValue;     @Transient   public Color getColor() {    return Color.fromValue(colorValue);   }     public void setColor(Color color) {    this.colorValue = color.toValue();   }  }  

Approach 3: Using a user defined business value – Recommended approach! This approach involves assigning a an explicit user defined value to each enum constant and defining a toValue() and fromValue() methods on the enum to do the serialization and deserialization.

public enum Color {   RED("RED"), GREEN("GREEN"), BLUE("BLUE"), UNKNOWN("UNKNOWN");     private final String value;     Color(String value) {     this.value = value;   }     public static Color fromValue(String value) {     if (value != null) {       for (Color color : values()) {         if (color.value.equals(value)) {           return color;         }       }     }       // you may return a default value     return getDefault();     // or throw an exception     // throw new IllegalArgumentException("Invalid color: " + value);   }     public String toValue() {     return value;   }     public static Color getDefault() {     return UNKNOWN;   }  }  public enum Color { RED("RED"), GREEN("GREEN"), BLUE("BLUE"), UNKNOWN("UNKNOWN"); private final String value; Color(String value) { this.value = value; } public static Color fromValue(String value) { if (value != null) { for (Color color : values()) { if (color.value.equals(value)) { return color; } } } // you may return a default value return getDefault(); // or throw an exception // throw new IllegalArgumentException("Invalid color: " + value); } public String toValue() { return value; } public static Color getDefault() { return UNKNOWN; } } This approach is better than approach 1 and approach 2 above. It neither depends on the order in which the enum constants are declared nor on the constant names.

explained the origin of GraniteDS and the differences with LiveCycle Data Services

ActionScript3 reflection API

GraniteDS 2.2

Integration with Seam 2.2

GraniteDS provides out-of-the-box integration with Seam 2.2 via either the RemoteObject API or the Tide API to remotely call Seam components, and fully supports serialization of JPA entities from and to your Flex application, taking care of lazily loaded associations