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Synchronization in JAVA

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You should be aware of Synchronization if you are working on an application where multiple threads are accessing the same resources or else it will show you erroneous or unforeseen results. Imagine a scenario where you are doing the multiple transactions in your bank. I believe you don’t want one thread is updating your balance and in parallel, the other thread is reading your balance otherwise you will end up in error or unexpected results. Example 1: Public class HDFCBank {             Protected long balanace =1000;             Public void deposit( int amount) {                         this.balance = this.balance + amount;             } } Assume if two threads, A and B are executing t...

FAQ Questions on Spring Boot

How to control logging with Spring Boot? By default, the SLF4j Logging is included in the Spring Boot starter package. To enable logging, create a  application.properties  file in the root of the  resources  folder. 1. application.properties logging.level.org.springframework.web=ERROR logging.level.com.waheedtechblog=DEBUG # Logging pattern for the console logging.pattern.console= "%d{yyyy-MM-dd HH:mm:ss} - %msg%n" # Logging pattern for file logging.pattern.file= "%d{yyyy-MM-dd HH:mm:ss} [%thread] %-5level %logger{36} - %msg%n" logging.file=/Users/waheed/application.log Similarly we can configure in application.yml as well. 2. application.yml logging:   level:     org.springframework.web: ERROR     com.waheedtechblog: DEBUG   pattern:     console: "%d{yyyy-MM-dd HH:mm:ss} - %msg%n"     file: "%d{yyyy-MM-dd HH:mm:ss} [%thread] %-5level %logger{3...

Database access with Spring boot

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The simplest way of creating Spring boot with MySQL application is via Spring starter project using STS (Spring Tool Suite) IDE. Steps: Create a new project by selecting spring starter project wizard Select project type as Maven, provide project name, packaging, and Java version etc. Select spring boot version and project dependencies After finishing, It will create the project structure with all required dependency. Configure MySQL configuration in application.properties file Now, Create the @Entity model ( User ) which should be persisted in the database . Hibernate will automatically translate entity class into a table. Create the repository (UserRepository.java ) . The Repository interface will be automatically implemented by Spring in a bean with the same name with changing case. For UserRepository, the bean name will be  userRepository . To handle HTTP request, Create a Controller class (UserController.java) having method POST a...