Reading and Writing Object Using ObjectMapper
We can use it to parse or deserialize JSON content into a Java object.
Java Object to JSON
ObjectMapper objectMapper = new ObjectMapper(); Car car = new Car(“yellow”, “renault”); objectMapper.writeValue(new File(“target/car.json”), car);
JSON to Java Object
String json = "{ \"color\" : \"Black\", \"type\" : \"BMW\" }";
Car car = objectMapper.readValue(json, Car.class);The readValue() function also accepts other…
Transaction simply represents a unit of work ,In such case, if one step fails, the whole transaction fails.
Hibernate Transaction Management
Transaction simply represents a unit of work ,In such case, if one step fails, the whole transaction fails.
Transaction is a Interface in Hibernate
- The methods of Transaction interface are as follows:
* void begin() starts a new transaction.
* void commit() ends the unit of work unless we are in FlushMode.NEVER.
* void rollback() forces this transaction to rollback.
* boolean wasCommited() checks if the transaction is commited successfully.
* boolean wasRolledBack() checks if the transaction is rolledback successfully.
A transaction is associated with Session and instantiated by calling session.beginTransaction().
Example of Transaction Management in Hibernate
Session session = null;
Transaction tx = null;
try {
session = sessionFactory.openSession();
tx = session.beginTransaction();
(Bussiness Logic)
tx.commit();
}catch (Exception ex) {
ex.printStackTrace();
tx.rollback();
}
finally {session.close();}
Export table in csv file By Using mysql command
SHOW VARIABLES LIKE “secure_file_priv”;
SELECT * FROM bootapplication into outfile ‘/ProgramData/MySQL/MySQL Server 8.0/Uploads/mysql_processes.csv’;
Export table in csv file by using workbench
Step1-
Step 2-
download Lombok jar
https://projectlombok.org/download
Goto lombok jar download location and run command
java -jar lombok-1.16.18.jar
Give Lombok Install Path
click on the “Specify Location” button and locate the eclipse.exe
Step 1: Generate Your SSH Key
ssh-keygen -t rsa -b 4096 -C “youreamil@example.com”
SSH Key on Windows
$ eval $(ssh-agent -s)
$ ssh-add ~/.ssh/id_rsa
Step 3: Add the SSH Key on GitHub
clip < ~/.ssh/id_rsa.pub
step 4 add ssh key in github/gitlab
/c/Users/****user name ****/.ssh/id_rsa.pub.
Step 1 — Run your Spring boot application
Step 2 -http://localhost:9001/h2-console/
port no- Application port no (9001)
Step 3- JDBC URL ,username and password application.yml or properties file
application.ymlserver:
port: 9001
spring:
application:
name: product-services
datasource:
driver-class-name: org.h2.Driver…
Static convenience methods for JavaBeans: for instantiating beans, checking bean property types, copying bean properties, etc.
Case 1- when you need to copy field value from one object to another object
public ProductAggregate(CreateProductCommand createProductCommand) {
ProductCreatedEvent productCreatedEvent = new ProductCreatedEvent();
BeanUtils.copyProperties(createProductCommand,productCreatedEvent);
}
// CreateProductCommand object value copy in ProductCreatedEvent
Copy…
