2. Using the Tutorial Examples
3. Getting Started with Web Applications
4. JavaServer Faces Technology
7. Using JavaServer Faces Technology in Web Pages
8. Using Converters, Listeners, and Validators
9. Developing with JavaServer Faces Technology
10. JavaServer Faces Technology: Advanced Concepts
11. Using Ajax with JavaServer Faces Technology
12. Composite Components: Advanced Topics and Example
13. Creating Custom UI Components and Other Custom Objects
14. Configuring JavaServer Faces Applications
16. Uploading Files with Java Servlet Technology
17. Internationalizing and Localizing Web Applications
18. Introduction to Web Services
19. Building Web Services with JAX-WS
20. Building RESTful Web Services with JAX-RS
21. JAX-RS: Advanced Topics and Example
23. Getting Started with Enterprise Beans
24. Running the Enterprise Bean Examples
25. A Message-Driven Bean Example
26. Using the Embedded Enterprise Bean Container
27. Using Asynchronous Method Invocation in Session Beans
Part V Contexts and Dependency Injection for the Java EE Platform
28. Introduction to Contexts and Dependency Injection for the Java EE Platform
29. Running the Basic Contexts and Dependency Injection Examples
30. Contexts and Dependency Injection for the Java EE Platform: Advanced Topics
31. Running the Advanced Contexts and Dependency Injection Examples
32. Introduction to the Java Persistence API
Requirements for Entity Classes
Persistent Fields and Properties in Entity Classes
Using Collections in Entity Fields and Properties
Validating Persistent Fields and Properties
Multiplicity in Entity Relationships
Direction in Entity Relationships
Queries and Relationship Direction
Cascade Operations and Relationships
Orphan Removal in Relationships
Embeddable Classes in Entities
Entity Inheritance Mapping Strategies
The Single Table per Class Hierarchy Strategy
The Table per Concrete Class Strategy
Container-Managed Entity Managers
Application-Managed Entity Managers
Finding Entities Using the EntityManager
Managing an Entity Instance's Lifecycle
Synchronizing Entity Data to the Database
Further Information about Persistence
33. Running the Persistence Examples
34. The Java Persistence Query Language
35. Using the Criteria API to Create Queries
36. Creating and Using String-Based Criteria Queries
37. Controlling Concurrent Access to Entity Data with Locking
38. Using a Second-Level Cache with Java Persistence API Applications
39. Introduction to Security in the Java EE Platform
40. Getting Started Securing Web Applications
41. Getting Started Securing Enterprise Applications
42. Java EE Security: Advanced Topics
Part VIII Java EE Supporting Technologies
43. Introduction to Java EE Supporting Technologies
45. Resources and Resource Adapters
46. The Resource Adapter Example
47. Java Message Service Concepts
48. Java Message Service Examples
49. Bean Validation: Advanced Topics
50. Using Java EE Interceptors
51. Duke's Bookstore Case Study Example
52. Duke's Tutoring Case Study Example
53. Duke's Forest Case Study Example
The Java EE 6 Tutorial
Java Coffee Cup logoThe Java Persistence API provides the following methods for querying entities.
The Java Persistence query language (JPQL) is a simple, string-based language similar to SQL used to query entities and their relationships. See Chapter 34, The Java Persistence Query Language for more information.
The Criteria API is used to create typesafe queries using Java programming language APIs to query for entities and their relationships. See Chapter 35, Using the Criteria API to Create Queries for more information.
Both JPQL and the Criteria API have advantages and disadvantages.
Just a few lines long, JPQL queries are typically more concise and more readable than Criteria queries. Developers familiar with SQL will find it easy to learn the syntax of JPQL. JPQL named queries can be defined in the entity class using a Java programming language annotation or in the application’s deployment descriptor. JPQL queries are not typesafe, however, and require a cast when retrieving the query result from the entity manager. This means that type-casting errors may not be caught at compile time. JPQL queries don’t support open-ended parameters.
Criteria queries allow you to define the query in the business tier of the application. Although this is also possible using JPQL dynamic queries, Criteria queries provide better performance because JPQL dynamic queries must be parsed each time they are called. Criteria queries are typesafe and therefore don’t require casting, as JPQL queries do. The Criteria API is just another Java programming language API and doesn’t require developers to learn the syntax of another query language. Criteria queries are typically more verbose than JPQL queries and require the developer to create several objects and perform operations on those objects before submitting the query to the entity manager.
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