Question 1

The JPA annotation @Basic specifies whether the column is optional and whether the corresponding data should loaded ________ (i.e., only when the data is accessed through the entity object) or ________ (i.e., loaded immediately when the entity object is created).

A) lazily, actively
B) slowly, eagerly
C) lazily, eagerly
D) idly, actively

lazily, eagerly

Accepted Answer

@Basic annotation specifies whether the data should be loaded lazily (i.e., only when the data is accessed through the entity object) or eagerly (i.e., loaded immediately when the entity object is created). There is no specification for loading data slowly or actively. Similarly, there is no specification for loading data idly, which is not a valid term in JPA.

Question 2

When you used JPA in this chapter, you interacted with an existing database via classes that the NetBeans IDE generated from the XE "database schema" database's schema. You used the NetBeans Entity Classes from Database… option to add to your project classes that represented the database tables. Together, these classes and the corresponding settings are known as a ________ unit.

A) perseverance
B) perpetual
C) sticky
D) persistence.

persistence.

Accepted Answer

The combination of classes generated from the database schema and the corresponding settings used to interact with the database is known as a persistence unit. JPA uses persistence units to manage the mapping between the application classes and the database schema.

Question 3

The first argument to EntityManager's XE &#34;EntityManager interface:createQuery method&#34; XE &#34;createQuery method of interface EntityManager&#34; createQuery method is a String written in ________.&#10;A) JPL&#10;B) JavaQL&#10;C) JPQL&#10;D) None of the above.

Accepted Answer

The first argument to EntityManager's createQuery method is a String written in JPQL (Java Persistence Query Language). JPQL is a query language that is similar to SQL but is optimized for object-oriented data. Therefore, choice C is the correct answer.

Question 4

Which of the following statements related to JPA is false?&#10;A) The Java Persistence API (JPA) maps Java classes to relational database tables and objects of those classes to rows in the tables. This is known as object-relational mapping.&#10;B) You can use the NetBeans IDE's object-relational mapping tools to select a database and autogenerate classes that use JPA to interact with that database. Your programs can then use those classes to query the database, insert new records, update existing records and delete records.&#10;C) Unlike JDBC, you will have to create mappings between your Java code and database tables, and you'll be able to perform complex database manipulations directly in Java.&#10;D) JPA can be used with any database management system that supports JDBC.

Accepted Answer

This statement is false as JPA provides automatic mapping between Java classes and database tables without the need for manual mapping, unlike JDBC. In addition, JPA abstracts away the complexity of database manipulation through its object-relational mapping, providing a straightforward way to interact with the database directly in Java.

Question 5

Which of the following JPA-related statements is false?&#10;A) You can update an existing entity by modifying its entity object in the context of a transaction.&#10;B) Once a transaction is committed, the changes to the entity are saved to the database.&#10;C) You can delete an existing entity.&#10;D) When you commit a transaction the entity is kept as a backup in the database.

Accepted Answer

When you commit a transaction, the changes to the entity are saved to the database but the entity itself is not kept as a backup. Once committed, the entity is considered persistent and can be retrieved or modified in future transactions.

Question 6

Which f the following JPA-related statements is false?&#10;A) You can use XE &#34;Interfaces:EntityManager&#34; XE &#34;EntityManager interface&#34; EntityManager method XE &#34;EntityManager interface:getTransaction method&#34; XE &#34;getTransaction method of interface EntityManager&#34; getTransaction to get the EntityTransaction that manages the transaction.&#10;B) You can use EntityTransaction method XE &#34;EntityTransaction interface:begin method&#34; XE &#34;begin method of interface EntityTransaction&#34; begin to start the transaction.&#10;C) You can use XE &#34;Interfaces:EntityManager&#34; XE &#34;EntityManager interface&#34; EntityManager method apply to insert a new entity into the database.&#10;D) You call EntityTransaction method XE &#34;EntityTransaction interface:commit method&#34; XE &#34;commit method of interface EntityTransaction&#34; commit to commit the changes to the database.

Accepted Answer

The EntityManager method apply does not exist in JPA. The correct method to insert a new entity into the database is persist. Therefore, statement C is false. The other statements are true.

Question 7

In JPA transaction processing, if the operations execute successfully, you call EntityTransaction method _______ to commit the changes to the database. If any operation fails, you call EntityTransaction method ________ to return the database to its state prior to the transaction.

A) apply, rollback
B) commit, restore
C) apply, restore
D) commit, rollback

Accepted Answer

In JPA transaction processing, if the operations execute successfully, you call EntityTransaction method _______ to commit the changes to the database. If any operation fails, you call EntityTransaction method ________ to return the database to its state prior to the transaction.

A) apply, rollback
B) commit, restore
C) apply, restore
D) commit, rollback

Question 8

Which of the following statements is false?&#10;A) For certain types of projects, NetBeans automatically includes JPA support, but not for simple Java Application projects.&#10;B) NetBeans projects do not include database drivers by default.&#10;C) Each Java Enterprise Edition (Java EE) API-such as JPA-has a reference implementation that you can use to experiment with the API's features and implement applications.&#10;D) The JPA reference implementation-which is included with the NetBeans Java EE version-is NetBeansLink.

Accepted Answer

The JPA reference implementation included with NetBeans Java EE version is not NetBeansLink. The correct name is EclipseLink.

Question 9

An object of type ________ is used to manage the data flow between the program and the database.&#10;A) XE &#34;Interfaces:EntityManager&#34; XE &#34;EntityManager interface&#34; EntityManager&#10;B) XE &#34;Interfaces:EntityManagerFactory&#34; XE &#34;EntityManagerFactory interface&#34; EntityManagerFactory XE &#34;Classes:Persistence&#34; XE &#34;Persistence class&#34;&#10;C) Persistence&#10;D) XE &#34;Interfaces:TypedQuery&#34; XE &#34;TypedQuery interface&#34; TypedQuery

Accepted Answer

The EntityManager interface is used to manage the persistence context and to interact with the database, facilitating operations such as create, read, update, and delete on entities.

Question 10

Which of the following JPA-related statements in false?&#10;A) An object that implements the TypedQuery generic interface performs queries and returns a collection of matching entities.&#10;B) To create queries, you can use EntityManager methods.&#10;C) The Java Persistence Query Language (JPQL) is quite similar to SQL.&#10;D) JPQL is optimized for dealing with relational database tables, rather than entity objects.

Accepted Answer

This statement is false because JPQL is actually optimized for working with entity objects, not relational database tables. JPQL allows you to write queries that work with your entity classes and their attributes, rather than with the underlying tables and columns of the database.

Question 11

For entity classes in JPA, an @NamedQueries annotation specifies a collection of ________ annotations that declare various named queries.&#10;A) @Entity-Specifies that the class is an XE &#34;entity class&#34; entity class.&#10;B) @Table-Specifies the entity class's corresponding database table.&#10;C) @NamedQuery&#10;D) None of the above.

Accepted Answer

The answer of For entity classes in JPA, an @NamedQueries...

Question 12

In JPA, when you compile the entity classes, the compiler looks at the annotations and adds JPA capabilities that help manage the interactions with the database-this is known as ________ capabilites.&#10;A) implanting&#10;B) injecting&#10;C) infusing&#10;D) instilling

Accepted Answer

The answer of In JPA, when you compile the entity...

Question 13

Which of the following statements about JPA database transaction processing is false?&#10;A) Transaction processing enables a program that interacts with a database to treat a set of operations as a single operation. Such an operation also is known as an atomic operation or a transaction.&#10;B) At the end of a transaction, a decision can be made either to commit the transaction or roll back the transaction.&#10;C) Committing a transaction finalizes the database operation(s); all insertions, updates and deletions performed as part of the transaction cannot be reversed.&#10;D) Rolling back the transaction leaves the database in its state prior to the database operation. This is useful when a portion of a transaction fails to complete properly.

Accepted Answer

The answer of Which of the following statements about JPA...

Question 14

An object that implements the EntityManager ________ manages the interactions between a program and the database.&#10;A) interface&#10;B) class&#10;C) enumeration&#10;D) None of the above.

Accepted Answer

The answer of An object that implements the EntityManager ________...

Question 15

With JPA, as part of a persistence unit, the IDE also creates a ________ package in the Source Packages folder.&#10;A) META-DATA&#10;B) PERSISTENCE-INF&#10;C) PU&#10;D) META-INF

Accepted Answer

The answer of With JPA, as part of a persistence...

Question 16

When you define a query in your own code, it's known as a(n) ________ query.&#10;A) dynamic&#10;B) static&#10;C) active&#10;D) passive

Accepted Answer

The answer of When you define a query in your...

Deck 27: Java Persistence Api Jpa