Software Development, Linux, and Windows

Notes on Software Development, Linux, and Windows

Options for spring.jpa.hibernate.ddl-auto

validate: validate the schema, makes no changes to the database. update: update the schema. create: creates the schema, destroying previous data. create-drop: drop the schema when the SessionFactory is closed explicitly, typically when the application is stopped.

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Configure SpringBoot with H2 Database

Prerequisite: Go to and create a new SpringBoot project with Web, H2, and DevTools for dependencies. Import new project into STS (Spring Tools Suite). Additions to Open /src/main/resources/ and add the following lines: # H2 spring.h2.console.enabled=true spring.h2.console.path=/h2 # Datasource spring.datasource.url=jdbc:h2:file:~/test spring.datasource.username=sa spring.datasource.password= spring.datasource.driver-class-name=org.h2.Driver spring.jpa.database-platform=org.hibernate.dialect.H2Dialect spring.jpa.generate-ddl=true spring.jpa.hibernate.ddl-auto=validate NOTE: If you want your database [...]

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Determine what Product Key was used for a Windows Install

This works for Windows 7, 8, and 10: The use case for this is that you have several licensed copies of the same Windows version, but do not remember which key you used on which computer. Open the Start Menu and type: cmd Type the following at the command prompt: slmgr -dli After about 15 [...]

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JPA: How to use a base class for your entities

In order for to extend a base class from you entities, you must use the annotation @MappedSuperclass on the base class: @MappedSuperclass public abstract class AbstractBaseEntity Then in your entity class extend the class as you usually would: @Entity public class MyConcreteEntity extends AbstractBaseEntity

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How to resolve LazyInitializationException with SpringMVC using JPA with Hibernate

Follow the below steps if you see the org.hibernate.LazyInitializationException being thrown while trying to render your page. Add a filter to your web.xml file: <filter> <filter-name>SpringOpenEntityManagerInViewFilter</filter-name> <filter-class></filter-class> </filter> <filter-mapping> <filter-name>SpringOpenEntityManagerInViewFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping>

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Install CentOS 7 Server with GUI

Boot from the CentOS 7 Installation DVD and select Install CentOS 7. Select language to use during the installation process and click [Continue]. You should now be at the Installation Summary screen. Under SOFTWARE, click Software Selection. Select Server with GUI and click [Done]. Note for this next part of configuring RAID 0 at the [...]

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Install and run Minecraft Server on CentOS 7 Server

Create a CentOS Installation DVD The first thing you need to do if you do not have it already is Create a CentOS Installation DVD Install CentOS 7 Server with GUI Follow the steps in this article to install CentOS 7, but note that you will want to use a static IP so that you [...]

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Handling Multiple Exceptions in one catch block

Overview Java 1.7 added support to handle more than one Exception in a single catch block. Example: This is a nice feature, and here is an example that demonstrates this and how to extract the name of the Exception class being thrown for logging: package com.petersarazin.exception; import; import org.junit.Test; public class ExceptionHandling_Test { @Test [...]

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Create a CentOS Installation DVD

Point your browser at Click the [Get CenotOS Now] button. Click the DVD ISO button. choose a mirror and download the .iso image. Burn the .iso image to a blank writable DVD.

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Open mysql on firewall in CentOS 7

Login or set user to root su – See the before of what services are open on the public zone firewall-cmd –zone=public –list-services Open up access to mysql on the public zone firewall-cmd –zone=public –add-service=mysql See the after of what services are open on the public zone firewall-cmd –zone=public –list-services Once verified, modify the permanent [...]

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