Create a JPA Repository

STEP 1: ExchangeValueRepository interface which extends JpaRepository


public interface ExchangeValueRepository extends JpaRepository<ExchangeValue, Long> {

//this method will give the implementation of given below method

//this is the magic of Spring data JPA,

//Once you provide method defination live given below you will get the implementation automaticaly

ExchangeValue findByFromAndTo(String from, String to);

}


STEP 2: Entity Class 

 @Entity

public class ExchangeValue {

@Id

private Long id;

@Column(name="currency_from")

private String from;

@Column(name="currency_to")

private String to;

@Column(name="conversion_multiple")

private BigDecimal conversionMultiple;

@Column(name="port")

private int port;

//Getter

//getter/setter for port

//default and param constructor

}



STEP 3: Controller Class


@RestController

public class CurrencyExchangeController {

@Autowired

private Environment environment;

@Autowired

private ExchangeValueRepository exchangeValueRepository;


@GetMapping("currency-exchange/from/{from}/to/{to}")

public ExchangeValue retrieveExchangeValue(@PathVariable String from, @PathVariable String to) {

ExchangeValue exchangeValue = exchangeValueRepository.findByFromAndTo(from, to);

exchangeValue.setPort(Integer.parseInt(environment.getProperty("local.server.port")));

return exchangeValue;

}

}

STEP 4: Application properties


spring.application.name=currency-exchange-service

server.port=8000


spring.jpa.show-sql=true

spring.h2.console.enabled=true


spring.datasource.url=jdbc:h2:mem:testdb;NON_KEYWORDS=USER

spring.h2.console.path=/h2-console

spring.jpa.defer-datasource-initialization=true

spring.data.jpa.repositories.bootstrap-mode=default


STEP 5: data.sql to intsert the default data



insert into exchange_value(id, currency_from, currency_to, conversion_multiple, port)

values(10001, 'USD', 'INR', 85,0);

insert into exchange_value(id, currency_from, currency_to, conversion_multiple, port)

values(10002, 'EUR', 'INR', 89, 0);

insert into exchange_value(id, currency_from, currency_to, conversion_multiple, port)

values(10003, 'AUD', 'INR', 53, 0);


Structur of the File


Database Data






by this code will get the exchange value From and to (your Database)


Query will be called from Code by given below url is

http://localhost:8000/currency-exchange/from/USD/to/INR


QUERY

Hibernate: select exchangeva0_.id as id1_0_, exchangeva0_.conversion_multiple as conversi2_0_, exchangeva0_.currency_from as currency3_0_, exchangeva0_.port as port4_0_, exchangeva0_.currency_to as currency5_0_ from exchange_value exchangeva0_ where exchangeva0_.currency_from=? and exchangeva0_.currency_to=?

Simplified Query


select * from exchange_value where currency_from='USD' and currency_to='INR'





Comments

Post a Comment

Popular posts from this blog

Microservice with Java Spring Cloud

Image
 Definations of Microservice: By Sam NewMan: - Small autonomous services that work together By James :- Style is an approach to developing a single application as a suit of small services, each running in its own process and commuinicating with lightweight mechanism, often an HTTP resourece API , These services are build around business capabilities and independently deployable by fully automated deployment machinery, there is a bare minimum of centralized management of these services, which may be ritten in different programming languagees and use different data storage technologies  MICROSERVICES REST and Small well chosen deployable units and Cloud Enable CHALANGEST WITH MICROSERVICE 1.  Bounded Context How to decided boundris of microservices id difficul 2.  Configuration Management Suppose we have 5 or 50 microservices, thse microservices have multiple instances in each environment and there are multiple environments Let say we have 10 microservices, with 5 env...
Read more

STEP 10 Configure Porfile for Limit service

Image
 Now by adding into bootrap.properties  the profile which you want to be in your Limit-Service spring.profiles.active= qa we are getting 2 as minimum but 888 is coming from default as maximum did not set into the limit-service-qa.properties this is default file it will pick up the value from the QA which is resited in the limits-service-qa.properties file spring.profiles.active= dev Similartly it will pick up the value from the DEV which is resited in the limits-service-dev.properties file 1. this is one of the way to pass in the active profile  2. And also add VM arguments spring.profiles.active-dev  3. Java command line arguments
Read more

STEP 9 Connect Limit service to Spring Cloud Config Server

Image
  Till now we have Connected the Spring cloud config server to GIT repository also configured with multiple environment as well But still we have not configured Limit service with spring cloud config server  In this Tutorial we will Connect LimitService to pick up the configuration from the spring cloud config server As of now all the properties are seted for limit service are present in application.properties STEP 1: Change application.properties to bootstrap.properties in Limit-service  STEP 2:   instead of using local service add the path of your spring-cloud-config-server spring.application.name= limits-service spring.cloud.config.uri= http://localhost:8888 Here is two Properties  1. spring.application.name this should be similar name of yoru spring-cloud-config-server file folder  2.  spring.cloud.config.uri this will contain the port information where our spring-cloud-config-server deployed Now able to achive the property of spring-cloud-...
Read more