how to use spring boot to run neo4j queries in java? - java

I spent a while trying to figure out spring boot neo4j in java. What I want is something like this
import org.neo4j.driver.v1.AuthTokens;
import org.neo4j.driver.v1.Driver;
import org.neo4j.driver.v1.GraphDatabase;
import org.neo4j.driver.v1.Record;
import org.neo4j.driver.v1.Session;
import org.neo4j.driver.v1.StatementResult;
import org.neo4j.driver.v1.Transaction;
import org.neo4j.driver.v1.Value;
public class adding {
static Driver driver;
public static void main(String args[]) throws JSONException {
StatementResult result;
driver = GraphDatabase.driver("bolt://localhost:7687", AuthTokens.basic("neo4j","password"));
Session session = driver.session();
result = session.run("CREATE (a:Person {name: bob} return a.name");
}
}
So this works an all however I'm looking to query with spring boot.
I followed this guide https://spring.io/guides/gs/accessing-data-neo4j/
and was left pretty confused. I'm not sure how I can immitate the above create process with spring boot . Is there like a query command?
package com.example.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
#SpringBootApplication
public class SpringGraphNeo4jApplication {
public static void main(String[] args) {
SpringApplication.run(SpringGraphNeo4jApplication.class, args);
}
}
The demo has this file and runs on a port.... I don't understand

Add #EnableNeo4jRepositories in you SpringGraphNeo4jApplication class
In case you want to use your own queries , use #query annotation on repository
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.data.neo4j.repository.config.EnableNeo4jRepositories;
#SpringBootApplication
#EnableNeo4jRepositories
public class SpringGraphNeo4jApplication {
private final static Logger log = LoggerFactory.getLogger(SpringGraphNeo4jApplication.class);
public static void main(String[] args) throws Exception {
SpringApplication.run(SpringGraphNeo4jApplication.class, args);
}
}

Related

Which is simpliest way to "threadify" a springboot application?

I start in java / springboot and I want to distribute an export function (initially a single class managed by SpingApplication), in several small classes performing an export chunk executed simultaneously.
/*
Here is my initial application class setted conventionally according to SpringBoot practice ...
Which works but it's too long
*/
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;
#SpringBootApplication
public class Application {
public static Logger logger = LoggerFactory.getLogger(Application.class);
public static void main(String[] args) {
ApplicationContext ctx = SpringApplication.run(Exporter.class, args);
Exporter exporter = ctx.getBean(Exporter.class);
exporter.main(args);
}
}
/* The runnable classe in Exporter.java*/
package moteur;
import config.ClauseWhereConfig;
import config.FtpConfig;
import config.PigeExportHighcoConfig;
import config.Sql2oConfig;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
#Configuration
#EnableAutoConfiguration
#Import({ ExportSession.class})
public class Exporter {
#Autowired
private ExportSession currentExport;
public static Logger logger = LoggerFactory.getLogger(Exporter.class);
public void main(String[] args) {
run(args);
}
public void run(String[] args) {
/*do some stuff ... */
}
/*
Then I tried this :
Each exporter instance is supposed to make a piece of "select from" original (as you know with the keyword limit <from>, <to>
*/
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;
import org.springframework.scheduling.annotation.EnableAsync;
#SpringBootApplication
#EnableAsync
public class Application {
public static Logger logger = LoggerFactory.getLogger(Application.class);
public static void main(String[] args) {
ApplicationContext ctx = SpringApplication.run(Exporter.class, args);
Exporter exporter1 = ctx.getBean(Exporter.class);
Exporter exporter2 = ctx.getBean(Exporter.class);
exporter1.setName("exporter1");
exporter2.setName("exporter2");
exporter1.start();
exporter2.start();
}
}
/* The Exporter class now extends Thread object */
#Configuration
#EnableAutoConfiguration
#EnableAsync
#Import({ ExportSession.class, Sql2oConfig.class, ClauseWhereConfig.class, FtpConfig.class, PigeExportHighcoConfig.class})
public class Exporter extends Thread {
#Autowired
private ExportSession currentExport;
public static Logger logger = LoggerFactory.getLogger(Exporter.class);
public void main(String[] args) {
run(args);
}
public void run(String[] args) {
logger.info(getName() + "---- >: Is running" ) ;
}
This foolish attempt that of course doesn't work :
Exception in thread "main" java.lang.IllegalThreadStateException
at java.lang.Thread.start(Thread.java:708)
at moteur.Application.main(Application.java:27)
In fact i'm loking for a solution for a small autonomous batch treatment
have you got this ?

not able to load netflix zuul route values from configuration class

I was trying my hands on netflix zuul api gateway technology. I was able to route my urls using application.properties file. But I was not able to do the same with third party configuration using ZuulProperties. This is a requirement. How can I do this. I tried below code:
config class code
package com.example.springbootzuulgatwayproxy;
import java.util.HashMap;
import java.util.Map;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.cloud.netflix.zuul.filters.ZuulProperties;
import org.springframework.cloud.netflix.zuul.filters.ZuulProperties.ZuulRoute;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
#Configuration
public class AppConfig {
#Primary
#Bean(name = "zuulConfigProperties")
#RefreshScope
#ConfigurationProperties("zuul")
public ZuulProperties zuulProperties() {
ZuulProperties.ZuulRoute route = new ZuulProperties.ZuulRoute("http://localhost:8090");// ZuulRoute is static inner class of ZuulProperties
Map<String,ZuulRoute> map = new HashMap<String,ZuulRoute>();
map.put("zuul.routes.employee.url", route);
ZuulProperties props = new ZuulProperties();
props.setRoutes(map);
return props;
}
}
here I am expecting that ZuulProperties will load the zuul.route property from inside my config class.. am I going wrong? As I had said, I could have done this easily using applicatin.properties. But this the requirement where I am stuck. To be frank, I want those properties to be loaded from database. But then I came across this piece of code, it was looking promising. But I am not able to do with this.
main class
package com.example.springbootzuulgatwayproxy;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.zuul.EnableZuulProxy;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import com.example.springbootzuulgatwayproxy.filters.ErrorFilter;
import com.example.springbootzuulgatwayproxy.filters.PostFilter;
import com.example.springbootzuulgatwayproxy.filters.PreFilter;
import com.example.springbootzuulgatwayproxy.filters.RouteFilter;
#ComponentScan
#SpringBootApplication
#EnableZuulProxy
public class SpringBootZuulgatwayproxyApplication {
public static void main(String[] args) {
SpringApplication.run(SpringBootZuulgatwayproxyApplication.class, args);
}
#Bean
public PreFilter preFilter() {
return new PreFilter();
}
#Bean
public PostFilter postFilter() {
return new PostFilter();
}
#Bean
public ErrorFilter errorFilter() {
return new ErrorFilter();
}
#Bean
public RouteFilter routeFilter() {
return new RouteFilter();
}
}
when I hit http://localhost:8080/employee/getEmployeeDetails/{employee_name} url, postman gives me 404 not found error.

Spring Boot MongoDB Repository null during unit test

I have been at this for a while but can't figure it out. The repo injects fine when running the app normal, but when trying to do a spring boot unit test it never injects. Here is the code:
package com.g2p.g2prestservice.repositories;
import com.g2p.g2prestservice.model.User;
import org.springframework.data.mongodb.repository.MongoRepository;
public interface UserRepository extends MongoRepository<User, Integer> {
}
package com.g2p.g2prestservice.repositories;
import com.g2p.g2prestservice.model.User;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import org.testng.annotations.Test;
import static org.testng.Assert.assertEquals;
#RunWith(SpringRunner.class)
#SpringBootTest
public class UserRepositoryTest {
#Autowired
UserRepository userRepository;
#Test
public void testInsertUser() {
User user = new User("fake#email.com", "fakePassword");
userRepository.save(user);
assertEquals(userRepository.count(), 1);
}
}
I am essentially trying to follow this guide as example: https://springframework.guru/configuring-spring-boot-for-mongo/
Thank you all for solving what I am sure is a very elementary mistake.
EDIT: I THINK the problem is that the spring context isn't launching when I run the test class...
EDIT: Here is launcher class:
package com.g2p.g2prestservice;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.data.mongodb.repository.config.EnableMongoRepositories;
#SpringBootApplication
public class G2pRestServiceApplication {
public static void main(String[] args) {
SpringApplication.run(G2pRestServiceApplication.class, args);
}
}
try this
#SpringBootTest(classes= {Application.class})
where Application.class is where you wrote you SpringApplication.run code.
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}

Field in com.XXX required a bean of type that could not be found

I'm working on Spring over Hibernate project an i'm only in the beginning.
I'm tryng to hav a SpringBootApplication which writes to MsSql some LogEntries objects.
I have some different packages:
here is the classes:
LogEntryFacadeImpl.class :
package com.tradingSystem.dataAccess;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import com.tradingSystem.entity.LogEntry;
#Service
public class LogEntryFacadeImpl implements LogEntryFacade{
#Autowired
private LogEntryDAO logEntryDao;
#Transactional
#Override
public Long addLogEntry(LogEntry log) {
return this.logEntryDao.save(log).getId();
}
#Override
public LogEntry getLogEntry(Long logId) {
return this.logEntryDao.findOne(logId);
}
}
LogEntryDAO.class:
package com.tradingSystem.dataAccess;
import org.springframework.data.jpa.repository.JpaRepository;
import com.tradingSystem.entity.LogEntry;
public interface LogEntryDAO extends JpaRepository<LogEntry, Long> {
}
and I use this class as tester:
TestApplication.class:
package com.testings;
import java.util.Date;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;
import com.tradingSystem.dataAccess.LogEntryFacade;
import com.tradingSystem.entity.LogEntry;
#SpringBootApplication
#ComponentScan({"com.tradingSystem" })
public class TestApplication implements CommandLineRunner{
#Autowired
private LogEntryFacade logEntryFacade;
public static void main(String[] args) {
SpringApplication.run(TestApplication.class, args);
}
#Override
public void run(String... args) throws Exception {
LogEntry log = new LogEntry(552266, "Testing of log entry save",
new Date(System.currentTimeMillis()),
new Date(System.currentTimeMillis()));
System.err.println(log);
Long id = logEntryFacade.addLogEntry(log);
LogEntry log2 = logEntryFacade.getLogEntry(id);
System.err.println(log2);
}
}
wher i run this as application i get this message in console:
APPLICATION FAILED TO START
Description:
Field logEntryDao in com.tradingSystem.dataAccess.LogEntryFacadeImpl required a bean of type 'com.tradingSystem.dataAccess.LogEntryDAO' that could not be found.
Action:
Consider defining a bean of type 'com.tradingSystem.dataAccess.LogEntryDAO' in your configuration.
I put the #ComponentScan({"com.tradingSystem" }) annotation in the tester as you can see. however, still get this message.
(when I didnt use any packages separation, everything works fine...)
Please help me solve this
Thanks
You should add #Repository annotation above your Repository interface.
Optionally you can add it like #Repository(value="logEntryRepository")
the default scan path is package of #SpringBootApplication class, so you must declare three scan path, but it's seems like that you missing two scan config, you need add
#EnableJpaRepositories(basePackages = "com.tradingSystem.dataAccess")
#EntityScan(basePackages = "com.tradingSystem.entity")
#ComponentScan(basePackages = "com.tradingSystem.dataAccess")
to the TestApplication class

Spring-Data-Rest Validator

I have been trying to add spring validators to a spring-data-rest project.
I followed along and setup the "getting started" application via this link: http://spring.io/guides/gs/accessing-data-rest/
...and now I am trying to add a custom PeopleValidator by following the documents here:
http://docs.spring.io/spring-data/rest/docs/2.1.0.RELEASE/reference/html/validation-chapter.html
My custom PeopleValidator looks like
package hello;
import org.springframework.validation.Errors;
import org.springframework.validation.Validator;
public class PeopleValidator implements Validator {
#Override
public boolean supports(Class<?> clazz) {
return true;
}
#Override
public void validate(Object target, Errors errors) {
errors.reject("DIE");
}
}
...and my Application.java class now looks like this
package hello;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.data.rest.webmvc.config.RepositoryRestMvcConfiguration;
#Configuration
#EnableJpaRepositories
#Import(RepositoryRestMvcConfiguration.class)
#EnableAutoConfiguration
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Bean
public PeopleValidator beforeCreatePeopleValidator() {
return new PeopleValidator();
}
}
I would expect that POSTing to the http://localhost:8080/people URL would result in an error of some kind since the PeopleValidator is rejecting everything. However, no error is thrown, and the validator is never called.
I have also tried manually setting up the validator as shown in section 5.1 of the spring-data-rest documentation.
What am I missing?
So it appears that the before/after "save" events only fire on PUT and PATCH. When POSTing, the before/after "create" events fire.
I tried it the manual way again using the configureValidatingRepositoryEventListener override and it worked. I'm not sure what I'm doing differently at work than here at home. I'll have to look tomorrow.
I sure would love to hear if others have suggestions on why it wouldn't work.
For the record, here is what the new Application.java class looks like.
package hello;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.data.rest.core.event.ValidatingRepositoryEventListener;
import org.springframework.data.rest.webmvc.config.RepositoryRestMvcConfiguration;
#Configuration
#EnableJpaRepositories
#Import(RepositoryRestMvcConfiguration.class)
#EnableAutoConfiguration
public class Application extends RepositoryRestMvcConfiguration {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Override
protected void configureValidatingRepositoryEventListener(ValidatingRepositoryEventListener validatingListener) {
validatingListener.addValidator("beforeCreate", new PeopleValidator());
}
}
Looks like the feature is currently not implemented (2.3.0), unluckily there are no constants for the event names otherwise the solution below would not be that fragile.
The Configuration adds all properly named Validator beans to ValidatingRepositoryEventListener using the right event.
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.ListableBeanFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.rest.core.event.ValidatingRepositoryEventListener;
import org.springframework.validation.Validator;
#Configuration
public class ValidatorRegistrar implements InitializingBean {
private static final List<String> EVENTS;
static {
List<String> events = new ArrayList<String>();
events.add("beforeCreate");
events.add("afterCreate");
events.add("beforeSave");
events.add("afterSave");
events.add("beforeLinkSave");
events.add("afterLinkSave");
events.add("beforeDelete");
events.add("afterDelete");
EVENTS = Collections.unmodifiableList(events);
}
#Autowired
ListableBeanFactory beanFactory;
#Autowired
ValidatingRepositoryEventListener validatingRepositoryEventListener;
#Override
public void afterPropertiesSet() throws Exception {
Map<String, Validator> validators = beanFactory.getBeansOfType(Validator.class);
for (Map.Entry<String, Validator> entry : validators.entrySet()) {
EVENTS.stream().filter(p -> entry.getKey().startsWith(p)).findFirst()
.ifPresent(p -> validatingRepositoryEventListener.addValidator(p, entry.getValue()));
}
}
}
A bit of a stab in the dark - I've not used spring-data-rest. However, after having a read of the tutorial you're following, I think the problem is that you need a PersonValidator not a PeopleValidator. Rename everything accordingly:
PersonValidator
package hello;
import org.springframework.validation.Errors;
import org.springframework.validation.Validator;
public class PersonValidator implements Validator {
#Override
public boolean supports(Class<?> clazz) {
return true;
}
#Override
public void validate(Object target, Errors errors) {
errors.reject("DIE");
}
}
Application
package hello;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.data.rest.webmvc.config.RepositoryRestMvcConfiguration;
#Configuration
#EnableJpaRepositories
#Import(RepositoryRestMvcConfiguration.class)
#EnableAutoConfiguration
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Bean
public PersonValidator beforeCreatePersonValidator() {
return new PersonValidator();
}
}
Another way of doing it is to use annotated handlers as specified here
http://docs.spring.io/spring-data/rest/docs/2.1.0.RELEASE/reference/html/events-chapter.html#d5e443
Here is an example of how to use annotated handlers:
import gr.bytecode.restapp.model.Agent;
import org.springframework.data.rest.core.annotation.HandleBeforeCreate;
import org.springframework.data.rest.core.annotation.HandleBeforeSave;
import org.springframework.data.rest.core.annotation.RepositoryEventHandler;
import org.springframework.stereotype.Component;
#Component
#RepositoryEventHandler(Agent.class)
public class AgentEventHandler {
public static final String NEW_NAME = "**modified**";
#HandleBeforeCreate
public void handleBeforeCreates(Agent agent) {
agent.setName(NEW_NAME);
}
#HandleBeforeSave
public void handleBeforeSave(Agent agent) {
agent.setName(NEW_NAME + "..update");
}
}
Example is from github edited for brevity.

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