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JPA @Embeddable and @Embedded

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Introduction: As an object-oriented developer, we want to avoid having larger classes with tons of unrelatable fields. And so, we might often feel the need to represent a JPA Entity using multiple objects. In this quick tutorial, we’ll learn how to achieve it using @Embedded and @Embeddable annotations in JPA or Hibernate. Context Buildup: Let’s say we have a person table with ...

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Pagination and Sorting with Spring Data JPA

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Learn Pagination and Sorting with Spring Data JPA with code examples. Understand how to get Paginated and Sorted results using Springs PagingAndSortingRepository interface. 1 Overview While dealing with large amount of data the lazy processing is often essential. Even if a service returns a huge amount of data the consumer is less likely using it. Consider a shopping website, where ...

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How to map PostgreSQL Enums to JPA entity properties using Hibernate

Introduction The open-source hibernate-types project allows you to map JSON, ARRAY, YearMonth, Month or database-specific columns (e.g. INET addresses). In this article, we are going to see how you can map a PostgreSQL Enum type to a Java array when using JPA and Hibernate. Maven dependency First of all, you need to set up the following Maven dependency in your ...

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OpenLiberty: Error on Injection, works on TomEE and Wildfly

While I was working on this blog, I encountered this error: [INFO ] DSRA8203I: Database product name : MySQL [INFO ] DSRA8204I: Database product version : 8.0.11 [INFO ] DSRA8205I: JDBC driver name : MySQL Connector/J [INFO ] DSRA8206I: JDBC driver version : mysql-connector-java-8.0.11 (Revision: 6d4eaa273bc181b4cf1c8ad0821a2227f116fedf) [INFO ] CWWJP9990I: test/wsjpa:wsjar:file:/home/dwuysan/dev/appservers/wlp/usr/servers/test/apps/expanded/test.war/WEB-INF/lib/d9f2b261-b3c6-4001-8a61-0aaebe46aa99.jar!/_testPU login successful [INFO ] WELD-000900: 2.4.5 (Final) [INFO ] FFDC1015I: ...

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Exact Matching of a String Containing a Wild Card in QueryDSL

On one of our recent projects, our client asked for a single search field that would be able to search on first name, last name and email address, with the only wildcard being an asterix ‘*’ for partial matches. Sounds simple, but it threw us for a little loop. In our project, we used QueryDSL in combination with JPA and ...

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Spring Data JPA Tutorial

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Managing data between java classes or objects and the relational database is a very cumbersome and tricky task. The DAO layer usually contains a lot of boilerplate code that should be simplified in order to reduce the number of lines of code and make the code reusable. In this tutorial, we will discuss spring data’s implementation of JPA. 1. Introduction ...

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