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kuni katsuya

JPA implementation patterns: Retrieving entities | Xebia Blog - 0 views

  • JPA implementation patterns: Retrieving entities
  • two ways to retrieve an entity with JPA:
  • EntityManager.find
  • ...2 more annotations...
  • Query object that can then be executed to return a list of entities or a single entity.
  • Keeping the query and the code that sets these parameters together makes them both easier to understand
kuni katsuya

Java EE Technical Documentation - 0 views

  • The Java EE 6 Tutorial
  • API Documentation
kuni katsuya

Comparing JSF Beans, CDI Beans and EJBs | Andy Gibson - 0 views

  • differences between CDI beans and EJBs is that EJBs are : Transactional Remote or local Able to passivate stateful beans freeing up resources Able to make use of timers Can be asynchronous
  • Stateless EJBs can be thought of as thread safe single-use beans that don’t maintain any state between two web requests
  • Stateful EJBs do hold state and can be created and sit around for as long as they are needed until they are disposed of
  • ...15 more annotations...
  • Stateless beans must have a dependent scope while a stateful session bean can have any scope. By default they are transactional, but you can use the transaction attribute annotation.
  • CDI beans can be injected into EJBs and EJBs can be injected into CDI beans
  • When to use which bean How do you know when to use which bean? Simple.
  • In general, you should use CDI beans unless you need the advanced functionality available in the EJBs such as transactional functions. You can write your own interceptor to make CDI beans transactional, but for now, its simpler to use an EJB until CDI gets transactional CDI beans which is just around the corner
  • Comparing JSF Beans, CDI Beans and EJBs
  • JSF Managed Beans
  • In short, don’t use them if you are developing for Java EE 6 and using CDI. They provide a simple mechanism for dependency injection and defining backing beans for web pages, but they are far less powerful than CDI beans.
  • JSF beans cannot be mixed with other kinds of beans without some kind of manual coding.
  • CDI Beans
  • includes a complete, comprehensive managed bean facility
  • interceptors, conversation scope, Events, type safe injection, decorators, stereotypes and producer methods
  • JSF-like features, you can define the scope of the CDI bean using one of the scopes defined in the javax.enterprise.context package (namely, request, conversation, session and application scopes). If you want to use the CDI bean from a JSF page, you can give it a name using the javax.inject.Named annotation
  • Comparing JSF Beans, CDI Beans and EJBs
  • Comparing JSF Beans, CDI Beans and EJBs
  • JSF Managed Beans
kuni katsuya

Java Persistence/Inheritance - Wikibooks, open books for an open world - 0 views

  • Inheritance
  • hardest part of persisting inheritance is choosing how to represent the inheritance in the database
  • There are three inheritance strategies defined from the InheritanceType enum,
  • ...101 more annotations...
  • SINGLE_TABLE
  • TABLE_PER_CLASS
  • JOINED
  • Single table inheritance is the default
  • @MappedSuperclass
  • @Inheritance
  • mapped superclass is
  • not a persistent class
  • but allow common mappings to be define for its subclasses
  • Single Table Inheritance
    • kuni katsuya
       
      implemented as a sparse table. ie. all attributes from all entities end up as columns in the 'super' table
  • single table is used to store all of the instances of the entire inheritance hierarchy
  • table will have a column for
  • every attribute
  • every class
  • in the hierarchy
  • discriminator column
  • is used to determine which class the particular row belongs to
  • abstract
  • Project
  • extends Project
  • extends Project
  • @DiscriminatorValue("S")
  • @DiscriminatorValue("L")
  • @DiscriminatorColumn(name="PROJ_TYPE")
  • @Inheritance
  • @Table(name="PROJECT")
  • single table inheritance
  • Joined, Multiple Table Inheritance
  • mirrors the object model in the data model
  • table is defined for each class in the inheritance hierarchy to store only the local attributes of that class
  • Each table in the hierarchy must also store the object's id (primary key), which is
  • only defined in the root class
  • share the same id attribute
  • joined inheritance
  • @Inheritance(strategy=
  • InheritanceType.JOINED
  • @DiscriminatorColumn(name="PROJ_TYPE")
  • @Table(name="PROJECT")
  • abstract
  • Project
  • @DiscriminatorValue("L")
  • @Table(name=
  • "LARGEPROJECT"
  • LargeProject
  • Project
  • @DiscriminatorValue("S")
  • @Table(name=
  • "SMALLPROJECT"
  • SmallProject
  • Project
  • Table Per Class Inheritance
  • Advanced
  • table is defined for
  • each concrete class
  • in the inheritance hierarchy to store
  • all the attributes
  • of that class and
  • all of its superclasses
  • table per class inheritance
  • @Inheritance(strategy=
  • InheritanceType.TABLE_PER_CLASS
  • abstract
  • Project
  • @Table(name="LARGEPROJECT")
  • LargeProject
  • Project
  • @Table(name="SMALLPROJECT")
  • SmallProject
  • Project
  • Mapped Superclasses
  • similar to table per class inheritance, but does not allow querying, persisting, or relationships to the superclass
  • mapped superclass
  • @MappedSuperclass
  • abstract
  • Project
  • @Column(name="NAME")
  • @Table(name="LARGEPROJECT")
  • LargeProject
  • Project
  • @AttributeOverride
  • "PROJECT_NAME"
  • "name"
  • @Table("SMALLPROJECT")
  • SmallProject
  • Project
  • cannot have a relationship to a mapped superclass
  • Joined, Multiple Table Inheritance
  • oined, Multiple Table Inheritance
  • abstract
  • abstract c
  • extends Project
  • Mapped Superclasses
  • Mapped Superclasses
  • apped Superclasses
  • allows inheritance to be used in the object model, when it does not exist in the data model
  • @MappedSuperclass
  • MappedSuperclass
  • abstract
  • abstract
  • extends Project
  • extends Project
kuni katsuya

Working with Events in CDI - NetBeans IDE Tutorial - 0 views

kuni katsuya

Release Notes - GraniteDS - Version 3.0.0.M1 - HTML format - Granite Data Services - 0 views

  • Release Notes - GraniteDS - Version 3.0.0.M1
  • GAS3 does not handle Java generics with abstract class implementations
  • Generated as3 has compilation warnings: missing constructor
  • ...1 more annotation...
  • Rename flex-filter to server-filter and @FlexFilter to @ServerFilter
kuni katsuya

[#GDS-933] GAS3 does not handle Java generics with abstract class implementations - Gra... - 0 views

  • GAS3 does not handle Java generics with abstract class implementations
  • Fix Version/s: 3.0.0.M1
kuni katsuya

Java Persistence/Relationships - Wikibooks, open books for an open world - 0 views

  • Map Key Columns (JPA 2.0)
  • Nested Collections, Maps and Matrices
  • List of Lists
  • ...58 more annotations...
  • Map of Maps,
  • Map of Lists
  • JPA does not support nested collection relationships
  • One solution is to create an object that wraps the nested collection.
  • Map<String, List<Project>>
  • Example nested collection model (original)
  • Example nested collection model (modified)
  • Map<String, ProjectType>
  • @MapKey(name="type")
  • mappedBy="employee"
  • employee
  • type;
  • List<Project>
  • ProjectType
    • kuni katsuya
       
      ProjectType wraps the original map value type List>
  • Maps J
  • JPA allows a Map to be used for any collection mapping including, OneToMany, ManyToMany and ElementCollection
  • @MapKey annotation
  • used to define a map relationship
  • @MapKey(name="type")
  • Map<String, PhoneNumber>
  • type;
  • mappedBy="owner"
  • owner
  • Map Key Columns (JPA 2.0)
  • Map Key Columns (JPA 2.0)
  • JPA 2.0 allows for a Map where the key is not part of the target object to be persisted. The Map key can be any of the following:
  • A Basic value, stored in the target's table or join table.
  • An Embedded object, stored in the target's table or join table.
  • A foreign key to another Entity, stored in the target's table or join table.
  • if the value is a Basic but the key is an Entity a
  • ElementCollection
  • mapping is used.
  • if the key is a Basic but the value is an Entity a
  • OneToMany
  • mapping is still used
  • a three way join table, can be mapped using a
  • ManyToMany with a MapKeyJoinColumn for the third foreign key
  • @MapKeyJoinColumn
  • used to define a map relationship where the
  • key is an Entity value
  • can also be used with this for composite foreign keys
  • @MapKeyClass
  • can be used when the key is an Embeddable
  • if generics are not used
  • @MapKeyColumn
  • Map<String, Phone>
  • mappedBy="owner"
  • owner
  • @MapKeyJoinColumn
  • PHONE_TYPE_ID
  • PHONE_TYPE_ID
  • Map<PhoneType, Phone>
  • mappedBy="owner"
  • owner
  • @MapKeyClass(PhoneType.class)
  • @Embeddable
  • PhoneType
  • Map<PhoneType, Phone>
  •  
    "Map Key Columns (JPA 2.0)"
kuni katsuya

Chapter 15. Data Management - 0 views

  • 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
  • ...5 more annotations...
  • highly recommended to use JPA optimistic locking in a multi-tier environment (@Version annotation)
  • Tip The easiest and recommended way for getting Tide enabled managed entities is to generate them from Java classes with Gas3 or the GDS Eclipse builder using the tide="true" option.
  • In a typical Flex/app server/database application, an entity lives in three layers: the Flex client the Hibernate/JPA persistence context the database
  • only invariant is the id.
  • id reliably links the different existing versions of the entity in the three layers
kuni katsuya

Java EE Compatibility - 0 views

kuni katsuya

Apache Geronimo : Index - 0 views

  • fully certified Java EE 5 application server
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