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best strategies for implementation of equals() and hashcode() in your persistent classes

The general contract is: if you want to store an object in a List, Map or a Set then it is an requirement that equals and hashCode are implemented so they obey the standard contract as specified in the  documentation

Why are equals() and hashcode() importantNormally, most Java objects provide a built-in equals() and hashCode() based on the object's identity; so each new() object will be different from all others.

Java 5 EnumUserType

Data Management

Tide provides an integration between the Flex/LCDS concept of managed entities and the server persistence context (JPA or Hibernate)

Tide maintains a client-side cache of entity instances and ensures that every instance is unique in the Flex client context

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.

In order to initialize GDS/Tide for CDI and Hibernate, you must add granite.jar, granite-Hibernate.jar and granite-cdi.jar to your WEB-INF/lib

The easiest way to add GraniteDS support to a CDI project in a Servlet 3 compliant container (currently only GlassFish v3) is by adding a configuration class in your project. This class will be scanned by the servlet 3 container and GraniteDS will use the annotation parameters to determine the application configuration

GraniteConfig.java import org.granite.config.servlet3.FlexFilter; import org.granite.gravity.config.AbstractMessagingDestination; import org.granite.gravity.config.servlet3.MessagingDestination; import org.granite.tide.cdi.CDIServiceFactory; import org.granite.tide.cdi.Identity; @FlexFilter( tide=true, type="cdi", factoryClass=CDIServiceFactory.class, tideInterfaces={Identity.class} ) public class GraniteConfig { }

The configuration of a GraniteDS project will generally involve the following steps : Add the GraniteDS jars to the WEB-INF/lib folder of the WAR file or the lib folder of the EAR file Add the GraniteDS listener, servlets and filters in the standard WEB-INF/web.xml configuration file Define the internal configuration of GraniteDS in the WEB-INF/granite/granite-config.xml file Define the application configuration of GraniteDS (remoting destinations, messaging topics...) in the WEB-INF/flex/services-config.xml

You will always need granite.jar

jar for your JPA provider (granite-hibernate.jar for hibernate)

Configuration for EJB 3 In order to initialize GDS/Tide for EJB 3 and Hibernate, you must add granite.jar and granite-Hibernate.jar to your WEB-INF/lib

Set break points in my Java code Start up the Java application server with the appropriate debug JVM properties set (e.g. -Xdebug -Xrunjdwp:transport=dt_socket,address=8000,server=y,suspend=n) From Eclipse, I attach a remote debugger to the app server on the default port 8000. The Java Debugger will open up when a break point is hit. Set breakpoints in my Flex application (or one of its modules). From Eclipse (with Flash Builder) I launch a debug configuration for my Flex app. The Flex Debugger will open up when a break point is hit. At this point I have two debuggers open and everything work great. Two other things I do: a) extend the transaction system timeout, so it doesn't get trigger while I am sitting there think for a few minutes b) use Charles Proxy (in reverse proxy mode) inbetween the client and server to watch the AMF traffic and view payloads, etc.

regarding the issue of selling Weld and EE6 to developers/shops....

How bout a JdbcTemplate Spring equivalent in the case of projects using legacy db schemas

portable extension to Weld

Open Session in View

WebORB for Java

Solid Alternative to Adobe LCDS and BlazeDS

drop-in replacement for Adobe Live Cycle Data Services (LCDS) and BlazeDS

Developing with Maven

artifacts are available in the Maven central repository

group org.graniteds