Implementing persistence layer may need some effort to configure and develop some DAO classes.

Spring-Data-JPA framework can simplify the creation of JPA based repositories and to reduce the amount of code needed to communicate with a database


Photo credit Ivan Kmit

This post is an introduction to Spring-Data-JPA. It describes, how you can configure the framewok when you are using Hibernate as your JPA provider.
In this post I will take profit from some Spring 4 new feature as generics autowiring to create generic service.
You can get the sample project from this link to start using Spring-Data-jpa and try some more advenced features.

1- Project dependencies

Spring-Data-JPA references a Spring 3 version. Maven will resolve dependencies by using Spring 3 version instead of version 4.

We need to exclude spring-core and spring-context and import Spring 4 version.

   <!-- Spring -->

2- Add an Entity

@Table(name = "users")
public class User {

    @GenericGenerator(name = "generator", strategy = "increment")
    @GeneratedValue(generator = "generator")
    @Column(name = "id", nullable = false)
    private Long id;

    @Column(name = "first_name", nullable = false)
    private String firstName;

    /* Add some extra attributes */     

    /* Add getters and setters */


3- Create repository

Declare an interface extending Repository.

import com.mycompany.myproject.persist.entity.User;
import org.springframework.data.jpa.repository.JpaRepository;

public interface UserRepo extends JpaRepository<User, Long> {

    User findByLogin(String login);


Spring-Data-JPA analyses the method name and generates a query using the JPA criteria.
Query generation is base on key words like (And, Or, Is, Equals, Between …). For more details, you can read the official Spring-Data-JPA documentation in this link.

4- Create Service

We make a choice to create a generic service that will reference the repository created in previous step.

One of the new features of Spring4 is generic types qualifier. We will take profit from this feature to inject repository by its generic interface.

public class GenericServiceImpl<T, D, ID extends Serializable> implements GenericService<T, D, ID> {

    private JpaRepository<T, ID> repository;

    private DozerBeanMapper mapper;

    protected Class<T> entityClass;

    protected Class<D> dtoClass;

    public GenericServiceImpl() {
        ParameterizedType genericSuperclass = (ParameterizedType) getClass().getGenericSuperclass();
        this.entityClass = (Class<T>) genericSuperclass.getActualTypeArguments()[0];
        this.dtoClass = (Class<D>) genericSuperclass.getActualTypeArguments()[1];

    public D findOne(ID id) {
        return mapper.map(repository.findOne(id), dtoClass);

    public List<D> findAll() {
        List<D> result = new ArrayList<D>();
        for (T t : repository.findAll()) {
            result.add(mapper.map(t, dtoClass));
        return result;
    public void save(D dto) {
        repository.saveAndFlush(mapper.map(dto, entityClass));


Next, we add UserService that extends GenericServcie.

public class UserServiceImpl extends GenericServiceImpl<User, UserDto, Long> {

5- Configure the project

  • line 15 : EnableJpaRepositories annotation enables scanning package to look for repository interfaces (created in staep 3).
  • line 21 : We use HSQL embedded database. We need to provide schema script and data script.

import javax.sql.DataSource;
import org.dozer.DozerBeanMapper;
import org.springframework.context.annotation.*;
import org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.jdbc.datasource.embedded.*;
import org.springframework.orm.jpa.*;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;

@ComponentScan({"com.mycompany.myproject.persist", "com.mycompany.myproject.service"})
public class JPAConfig {

    @Bean(name = "dataSource")
    public DataSource dataSource() {
        return new EmbeddedDatabaseBuilder().setType(EmbeddedDatabaseType.HSQL).setName("myDb")

    @Bean(name = "entityManagerFactory")
    public LocalContainerEntityManagerFactoryBean entityManagerFactoryBean() {
        LocalContainerEntityManagerFactoryBean factoryBean = new LocalContainerEntityManagerFactoryBean();
        factoryBean.setPackagesToScan(new String[] { "com.mycompany.myproject.persist" });
        HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        return factoryBean;

    public PlatformTransactionManager transactionManager() {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        return transactionManager;

    public PersistenceExceptionTranslationPostProcessor exceptionTranslation() {
        return new PersistenceExceptionTranslationPostProcessor();

    public DozerBeanMapper getMapper() {
        return new DozerBeanMapper();

6- Test your application

@ContextConfiguration(classes = {JPAConfig.class })
public class GenericServiceTest {
	private GenericService<User, UserDto, Long> userService;
    private GenericService<Authority, AuthorityDto, Long> authorityService;
	public void testFindOneUser() {
		UserDto userDto = userService.findOne(1L);
		Assert.assertEquals(1, userDto.getId().longValue());
    public void testFindOneAuthority() {
        AuthorityDto authorityDto = authorityService.findOne(1L);
        Assert.assertEquals(1, authorityDto.getId().longValue());
    public void testFindAll() {
        List<AuthorityDto> authorities = authorityService.findAll();
    public void testSave() {
        AuthorityDto authorityDto = new AuthorityDto();
        authorityDto.setName("test authority");

If you are a concise code adept you will appreciate using Spring-Data-JPA. To get your repositories you just need to add some interfaces for entities. You don’t need to write redundant basic code for each persistent bean.

The mix of Spring-DATA-JPA and Spring4 gives some extra possibilities to write generic code for the persistence layer.

Logback – Dynamic creation of log files

Some project have some log constraints that are difficult to implements with Log4j.

Logback is an alternative to log4j. It gives you more possibilities and it can easily implements your log policies.


Origami by Brian Chan

In this post, I present a simple of Logback configuration for a maven project. This configuration implements a dynamic log files generation.

Sample project description

This post example is inspired from a batch log policy I dealt with. The batch processes N files and generates two logs for each processed file. The first one is a summary of logs with no stack trace for functional users and the second one is a detailed log for programmers.

The picture bellow presents this case of study.

Below the summary of log policies to implement:

  1. Logging errors without stacktrace.
  2. Dynamic file logging (switch to new log file).
  3. Read logging directory from application properties file.
  4. Create log files name with timestamp.

1. Add Maven dependency

First we need to add Slf4j and logback dependency to the project.






2. Create a costom layout Class

To customise logging layout, we create a class which extends LayoutBase and override the doLayout method.

public class CustomLogLayout extends LayoutBase<ILoggingEvent>{

	public String doLayout(ILoggingEvent event) {
		StringBuffer sbuf = new StringBuffer(128);
	    sbuf.append(new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date(event.getTimeStamp())));
	    sbuf.append(" ");
	    sbuf.append(String.format("%-6s", event.getLevel()));
	    sbuf.append(" ");
	    if((event.getLevel() == Level.ERROR || event.getLevel() == Level.WARN) && event.getThrowableProxy() !=null) {
	    	sbuf.append(" - ");
	    	sbuf.append(StringUtils.substringBefore(event.getThrowableProxy().getMessage(), IOUtils.LINE_SEPARATOR));
	    return sbuf.toString();


3. Logback configuration

In this step we create Logback.xml config file that will use the costomLayout we created in the previous step and will implements the logs policies.

  • Line 3 indicates the path to properties file where it will look for some values. In our case the path is a system property.
  • Line 5 specifies a key for the timestamp value.
  • STIF appender creates a custom log files with the CustomLogLayout class.
  • loggerFileName is a MDC (Mapped Diagnostic Contexts) property. Changing this value will generate a new file.
  • SIFT-TRACE appender creates a verbose log file and it uses logback.classic.PatternLayout.


	<property file="${appli.config.path}" />

	<timestamp key="bySecond" datePattern="yyyyMMddHHmmss" />

	<appender name="SIFT" class="ch.qos.logback.classic.sift.SiftingAppender">

		<filter class="ch.qos.logback.classic.filter.ThresholdFilter">
			<appender name="FILE-${loggerFileName}" class="ch.qos.logback.core.FileAppender">
				<encoder class="ch.qos.logback.core.encoder.LayoutWrappingEncoder">
					<layout class="com.mycompany.log.CustomLogLayout" />

	<appender name="SIFT-TRACE" class="ch.qos.logback.classic.sift.SiftingAppender">
			<appender name="TRACE-${loggerFileName}" class="ch.qos.logback.core.FileAppender">
				<layout class="ch.qos.logback.classic.PatternLayout">
					<Pattern>%d %-5level %logger{5} - %msg%n</Pattern>

	<logger name="org.springframework" level="ERROR" />
	<root level="DEBUG">
		<appender-ref ref="SIFT" />
		<appender-ref ref="SIFT-TRACE" />


4. Test config

In this step we test the logback configuration.

setup() method set system property for the properties file path where logback will look for loging directory path.

The test simulates processing N files and at the end it verifies that we have 2xN log files.

public class LogTest {

	private static final int TEST_FILE_NUM = 5;

	private static final File TEST_DIR = new File(System.getProperty("java.io.tmpdir"), "logbak-test-dir");

	public void setUp() throws IOException {
		System.setProperty("appli.config.path", ClassLoader.getSystemClassLoader().getResource("logback.properties").getPath());

	public void testLogbackFileConfig() throws InterruptedException {

		Logger logger = LoggerFactory.getLogger(LogTest.class);

		// assume SLF4J is bound to logback in the current environment
		LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
		JoranConfigurator configurator = new JoranConfigurator();

		try {
		} catch (JoranException je) {
			Assert.fail("Erreur de chargement des paramètre logback");

		for (int i = 1; i <= TEST_FILE_NUM; i++) {
			MDC.put("loggerFileName", "file" + i);
			logger.info("log in File{}", i);
			logger.debug("log in File{}", i);
			logger.error("log in File" + i, new Exception("My test exception", new Exception("my cause of exception")));

		Assert.assertEquals(TEST_FILE_NUM * 2, TEST_DIR.listFiles().length);

JUnit test with Mockito and Spring

It is important to be able to perform some integration testing without requiring deployment to your application server or connecting to other enterprise infrastructure.

This could be done in your Spring project by using Spring-test library and Mockito framework.


Photo credit: Honey

In this post, I present a simple way to create a mock and to inject it into a tested bean.

Preparation of testing with Mockito

To make Mockito available, we need to add following dependency in the pom.xml file.


Deveop Mockito, Spring and JUnit tests

The code source bellow presents a JUnit test using Spring-test and Mockito framework.

  • @RunWith(SpringJUnit4ClassRunner.class) runs the test with Spring custom runner that will load Spring application context.
  • @Autowire associate invoiceService reference to the InvoiceService instance.
  • @Before annotation executes the setup method before the test.
  • MockitoAnnotations.initMocks(this) scans the class annotation, instanciates invoiceDaoMock and inject it into the InvoiceService bean.
  • when(.(any())).thenReturn() associates a return value with method execution parameters.

import static org.mockito.Mockito.*; 

//Load Spring contexte
@ContextConfiguration(locations = {"classpath:/application-context.xml"})
public class InvoiceServiceTest {
	// Create Mock
	private IInvoiceDao invoiceDaoMock;
	private IInvoiceService invoiceService;
	public void setUp() {

	public void testProcessInvoice() throws SQLException {
		// specify mock behave when method called
		Map<Product, Integer> products = new HashMap<Product, Integer>();
		products.put(new Product("labtop", BigDecimal.valueOf(1255.50)), 2);
		Invoice invoice = invoiceService.processInvoice(products);
		Assert.assertEquals(1255.50 * 2, invoice.getTotal().doubleValue(), 0);

Web Services with Apache CXF

CXF framework is widely used to create web services. It supports a variety of protocols such as SOAP, XML/HTTP, RESTful HTTP, or CORBA and work over a variety of transports such as HTTP, JMS or JBI.

CXF has some tools like wsdl2java witch generate web service code from WSDL. This tool is very useful but it integrates some code that usually we don’t control all its details.

Photo credit: Brian A Jackson

I wrote this article to presents a concise way to create a web service with CXF and Spring. This solution has the advantage to avoid generating extra code to integrate in your project.

1 – CXF dependency

If you are using Maven you can add dependency by adding the XML code below.


2 – Web service implementation

First, add a web service interface. The code source bellow is a simple of web service that allows adding a customer to an existent JSF web application.

import javax.jws.WebService;
import com.mycompany.entity.Customer;

public interface CustomerService {

	String SaveCustomer(Customer customer);


Next, write your web service implementation.

import javax.jws.WebService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import com.mycompany.dao.ICustomerDao;
import com.mycompany.entity.Customer;

@WebService(endpointInterface = "com.mycompany.service.CustomerService")
public class CustomerServiceImpl implements CustomerService {
private ICustomerDao customerDao;

	public String SaveCustomer(Customer customer) {
		return "saved";

Finally, add spring configuration to configure the web service end point and client.

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:jaxws="http://cxf.apache.org/jaxws"
	http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
	http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd">

	<import resource="classpath:META-INF/cxf/cxf.xml" />
	<import resource="classpath:META-INF/cxf/cxf-extension-soap.xml" />
	<import resource="classpath:META-INF/cxf/cxf-servlet.xml" />

	<jaxws:endpoint id="customerServiceEndPoint" implementor="#customerService"
		address="/CustomerService" />

	<jaxws:client id="customerServiceClient" serviceClass="com.mycompany.service.CustomerService"
		address="http://localhost:8080/myApp_JSF_CXF/ws/CustomerService" />

3 – Web service test

Test with SoapUi
You can use SoapUi to test your web service. In this case you don’t need to implemente a service client.

SoapUi needs a wsdl file. You can provide this URL http://localhost:8080/myApp_JSF_CXF/ws/CustomerService?wsdl.

Test with JUnit

Testing a web service with junit it’s more likely to be an integration test than a unit test because it depends on other resources. You will need to start your application server and deploy your web service before running your test.

The code source bellow uses the web service client to test the web service developed in this article.

public class CustomerServiceTest {
	private CustomerService customerServiceClient;

	public void SaveCustomerClientTest() {
		Customer customer = new Customer(25, "nameTest","adresse", "city", "state", "123", "0606060606", null);
		assertEquals("saved", customerServiceClient.SaveCustomer(customer));