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Tag Archives: JPA

Compile-time checking JPA queries

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JPA provides several alternatives for querying data. Such alternatives may be classified attending to a variety of criteria, eg, language used (SQL vs JPQL) or whether queries are static (compilation time) or dynamic (execution time). Static queries are defined using annotations @NamedQuery (javax.persistence.NamedQuery) and @NamedQueries (javax.persistence.NamedQueries) in the @Entity class definition itself:         @NamedQuery( name="findAllCustomersWithName", query="SELECT c ...

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A beginner’s guide to JPA/Hibernate flush strategies

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Introduction In my previous post I introduced the entity state transitions Object-relational mapping paradigm. All managed entity state transitions are translated to associated database statements when the current Persistence Context gets flushed. Hibernate’s flush behavior is not always as obvious as one might think.       Write-behind Hibernate tries to defer the Persistence Context flushing up until the last ...

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From JPA to Hibernate’s legacy and enhanced identifier generators

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JPA identifier generators JPA defines the following identifier strategies:                 Strategy Description AUTO The persistence provider picks the most appropriate identifier strategy supported by the underlying database IDENTITY Identifiers are assigned by a database IDENTITY column SEQUENCE The persistence provider uses a database sequence for generating identifiers TABLE The persistence provider uses a ...

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How to use a JPA Type Converter to encrypt your data

java-interview-questions-answers

A few days ago, I read an interesting article by Bear Giles about Database encryption using JPA listeners from 2012. He discusses his requirement for an encryption solution and provides a code example with JPA listeners. His main requirements are: provide a transparent encryption that does not affect the application, be able to add the encryption at deployment time, develop ...

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JPA 2.1 Type Converter – The better way to persist enums

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Persisting enums with JPA 2.0 is possible, but there is no nice way to do it. Using the @Enumerated annotation, you can use EnumType.ORDINAL or EnumType.STRING to map the enum value to its database representation. But both options have some drawbacks, that we will discuss in the first part of this article. In the second part, I will show you ...

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SpringMVC4 + Spring Data JPA + SpringSecurity configuration using JavaConfig

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In this article we will see how to configure and integrate SpringMVC4, Spring Data JPA with Hibernate and SpringSecurity using JavaConfig. 1. First let’s configure all the necessary dependencies in pom.xml                 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.sivalabs</groupId> <artifactId>spring-javaconfig</artifactId> <version>1.0</version> <packaging>war</packaging> <name>SpringApp JavaConfig Demo</name> <properties> <java.version>1.7</java.version> <junit.version>4.11</junit.version> <slf4j.version>1.7.5</slf4j.version> <logback.version>1.0.13</logback.version> <spring.version>4.0.0.RELEASE</spring.version> <spring-data-jpa.version>1.4.1.RELEASE</spring-data-jpa.version> <spring-security.version>3.2.0.RELEASE</spring-security.version> ...

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