Learn to configure the Log4j2 provided JDBCAppender that writes log events to a relational database table using standard JDBC. The JDBCAppender obtains the database connection from a configured connection factory or JNDI datasource. Then it uses the provided column configuration to insert a new row in the log table, everytime a log statement is executed. … Read more
Learn to execute multiple Spring batch jobs using quartz scheduler and persistent database storage recording used by quartz to record jobs and trigger information. I am using H2 database with web console enabled to view data in DB tables. You can select DB as per your requirement.
If you are working on Hibernate and HSqlDB, and you are trying to fetch collection of entities, then you may face this error. For single entity you may or may not find this error. Exception will look like this: Solution This error is due to version mismatch of hibernate and hsqldb. Trying updating latest verion … Read more
Using custom SQL scripts in spring to initialize the database at startup of application with appropriate tables and data populated inside it.
Learn the fundamentals of working with S3 buckets and objects using Spring Cloud AWS library and its S3Client and S3Template classes.
If you’re preparing for a job interview, these Spring security interview questions will help you understand key concepts and increase the confidence.
Learn to use Redis Pub/Sub with Spring Boot Data, and configure the message publishers and subscribers (listners) for a given channel topic.
After WebSecurityConfigurerAdapter was first deprecated and then removed in Spring Security 6, this tutorial will help in migrating to the latest version.
In Spring security tutorial, learn how it works under the hood, concepts of authentication, authorization, access control and basic configurations.
Step by step, we will learn to deploy a Spring Boot application to AWS Elastic Beanstalk which uses RDS for persisting the records in the database.
Learn the installation of the Keycloak authorization server as a docker container and different configurations for setting up the realm and testing the authorization token flow.
Learn to implement authentication with a user login and logout functionality using Vue.js and Spring Boot Security using JWT tokens.
Spring @Sql executes DDL and DML SQL scripts and statements during the integration testing. @SqlGroup groups multiple @Sql statements.
Learn to execute SQL scripts to load data (e.g. import.sql, schema.sql or data.sql) during startup of a Spring boot application or tests.
Learn to solve the ‘JdbcSQLSyntaxErrorException schema not found’ error in a Spring boot app that uses the H2 database for CRUD operations.
In this post, we will learn how to configure and manage multiple datasources using properties configuration and defining custom beans using Java annotations in Spring Boot. Note that this requirement differs from having separate datasource in test, dev and prod environments. Here, we are using multiple datasources in the same environment and each datasource can … Read more
Learn to configure and use different DataSource in different environments (test, development, production etc.) using the Spring profile specific properties files, as well as Java configuration in a Spring boot application. 1. Introduction A production grade application is deployed and tested in different environments before finally released to the end-user. In these environments, application must … Read more
Learn to install the database services such as MySQL and PostgreSQL as docker containers and connect to them from Adminer or Spring boot app.
Learn the basics and internals of Testcontainers with an example of a JUnit 5 test that uses a MongoDB client in Spring Boot application
Learn how to enable SQL logging in a Spring boot Data JPA application, print SQL statements and prepare statements with parameter values.
Learn to configure MyBatis with Spring Boot 3 and configure @Mapper and DataSource. Also, learn mapper scanning with @MapperScan with example.
In this Spring boot with Angular tutorial, learn to create REST APIs using Spring boot and call from Angular to create a CRUD application.
Spring batch is a lightweight, comprehensive framework designed for the development of robust batch processing applications. Learn with examples.
This guide lists out a few of the most asked SQL interview questions and gives their answers such as JOINS, KEYWORDS, TRIGGERS and much more.
On this page, we will frequently list the major feature changes in the latest Java release, sequentially. Though we have tried to cover as much information as possible, if you know something we have missed below, please let me know, and we will add that information. Java 18 Features Java 18 GA was released on … Read more
Learn about Spring profiles, @Profile, profile-specific beans and properties, profile groups and activating a certain profile during startup.
Learn to use @PropertySource, @Value and @ConfigurationProperties annotations to register property files and inject configuration properties.
Learn to configure OAuth2 authorization-based login security in a Spring boot and spring security application with custom handlers.
Learn to configure and test a spring security login form based authentication that fetches the username, password and roles from the database.
Learn the contract spring security expects from PasswordEncoder interface, inbuilt implementations and DelegatingPasswordEncoder with examples.
This Java logging series lists down all tutorials posted under logging frameworks such as Log4j2 and Logback, for quick references.
Log4j2 provides significant improvements over its predecessor Log4j. Read about its xml and properties configuration and various examples.
These tutorials have been published to help you start with persistence with Hibernate and JPA. These are updated to version Hibernate 6.x.
Learn to create and inject an in-memory DataSource that can be used to mock J2EE container provided JNDI DataSource without running a server.
Learn to execute bulk SQL INSERT and UPDATE statements using Hibernate / JPA batch processing, and to configure session-specific batch sizes.
Hibernate provides support for executing the stored procedures and capturing their outputs using StoredProcedureQuery and ProcedureCall APIs.
Learn to implement and test the pagination functionality in hibernate using the HQL setFirstResult(), setMaxResults() and ScrollableResults.
Learn to initialize the EnitytManager using the XML configuration and the programmatic configuration in hibernate 6 and Jakarta persistence.
Learn to map Java 8 classes (LocalDate, LocalTime or LocalDateTime etc) to SQL types while storing the time-based values in the database.
HikariCP is a lightweight JDBC connection pool. Learn about various options for configuring the HikariCP with Spring boot JPA and hibernate.
Learn how to test a Spring boot web application. We will see some very quick examples (using Junit 5) and configurations for : For demo purposes, we have created a very simple Employee management application. It has a few CRUD API calls for creating, fetching and deleting the employees from the database. Do not forget … Read more
Learn to build hateoas links for REST resources using RepresentationModel and RepresentationModelAssemblerSupport in a Spring boot application example.
Learn to use Spring batch partitioning to use multiple threads to process a range of data sets in a spring boot application. 1. Parallel Processing and Step Partitioning 1.1. Parallel Processing Mostly batch processing problems can be solved using a single-threaded, but a few complex scenarios like single-threaded processing taking a long time to perform … Read more
Learn to use the Spring batch Classifier with Composite Item Writer to classify the data and write to multiple destinations.
Spring boot @DataJpaTest annotation focuses on JPA components and apply configuration only relevant to JPA tests. It helps in testing @Repository classes.
Spring boot @Repository annotation is a specialization of the @Component to indicate a data repository used for storage, retrieval, and search behavior.
Spring boot makes application development easier but we may face some tough interview questions when it comes to test your knowledge on how it all works. Be prepare for the next job interview with given Spring boot interview questions and answers.
Learn how to create and customize DataSource bean in Spring boot applications and configure connection pooling and multiple datasource beans.
Learn about the most widely used spring annotations. In this tutorial, we will briefly cover the important annotations which are provided by spring core to define beans and create complex application context configurations. 1. Bean annotations Given list of annotations are used to define beans in spring and to control their registration preferences in application … Read more
Learn to write unit tests and integration tests in spring boot applications along with spring test context, test annotations and bean mocking support.
HowToDoInJava provides tutorials and how-to guides on Java and related technologies.
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