JFairy

Jfairy is a Java fake data generator project and this time I will show you how to use this library to generate random testing information data. First let’s create an empty basic Java project using lazybones. In order to install lazybones in your computer, please use this tool: sdkman. Then execute this command from your command line:

lazybones create java-basic jfairy-workshop

You should get this output:

Creating project from template java-basic (latest) in 'jfairy-workshop'

Java Application project template
------------------------------------

You have just created a basic Java application. There is a standard project
structure for source code and tests.

In this project you get:

* A Gradle build file
* A standard project structure:

    <proj>
      |
      +- src
          |
          +- main
          |     |
          |     +- java
          |
          +- test
          |   |
          |   +- java

Project created in jfairy-workshop!

Next step is to edit your build.gradle file and add JFairy, Junit5 and Apache Commons Lang3 dependencies

implementation 'com.devskiller:jfairy:0.6.2'
implementation('org.apache.commons:commons-lang3:3.9')
testImplementation "org.junit.jupiter:junit-jupiter-api:$junitJupiterVersion"
testRuntime "org.junit.jupiter:junit-jupiter-engine:$junitJupiterVersion"

Now, please consider the following example how to create a fake data Company

package com.jos.dem.jfairy.workshop;

import static org.junit.jupiter.api.Assertions.assertAll;
import static org.junit.jupiter.api.Assertions.assertTrue;
import static org.junit.jupiter.api.Assertions.assertNotNull;

import org.apache.commons.lang3.builder.ToStringBuilder;

import com.devskiller.jfairy.Fairy;
import com.devskiller.jfairy.producer.company.Company;

import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.DisplayName;

import java.util.logging.Logger;

class CompanyTest {

  private static final String VAT_REGEX = "[0-9]{2}-[0-9]{7}";
  private static final String DOMAIN_REGEX = "[a-zA-Z]+.[a-zA-Z]{2,10}";

  private Company company = Fairy.create().company();

  private static final Logger log = Logger.getLogger(CompanyTest.class.getName());

  @Test
  @DisplayName("Should validate company")
  void shouldValidateCompany() {
    log.info("Running: Should validate information from company: " + ToStringBuilder.reflectionToString(company));

    assertAll("company",
        () -> assertNotNull(company.getName(), "should get a name"),
        () -> assertTrue(company.getDomain().matches(DOMAIN_REGEX), "should have a valid domain"),
        () -> assertTrue(company.getVatIdentificationNumber().matches(VAT_REGEX), "should have a valid vat number")
        );
  }

}

Once you execute this test case, you should get an output similar to this one:

INFO: Running: Should validate information from company: com.devskiller.jfairy.producer.company.Company@612724ad[name=Adapt LLC,domain=adaptllc.biz,email=info,vatIdentificationNumber=83-0004026]

It is time to see another example, a person:

package com.jos.dem.jfairy.workshop;

import static org.junit.jupiter.api.Assertions.assertAll;
import static org.junit.jupiter.api.Assertions.assertTrue;
import static org.junit.jupiter.api.Assertions.assertNotNull;

import org.apache.commons.lang3.builder.ToStringBuilder;

import com.devskiller.jfairy.Fairy;
import com.devskiller.jfairy.producer.person.Person;
import com.devskiller.jfairy.producer.company.Company;

import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.DisplayName;

import java.util.logging.Logger;

class PersonTest {

  private static final String PHONE_REGEX = "[0-9]{3}-[0-9]{3}-[0-9]{3,4}";
  private static final String VAT_REGEX = "[0-9]{2}-[0-9]{7}";
  private static final String DOMAIN_REGEX = "[a-zA-Z]+.[a-zA-Z]{2,10}";

  private Person person = Fairy.create().person();

  private static final Logger log = Logger.getLogger(PersonTest.class.getName());

  @Test
  @DisplayName("Should validate person")
  void shouldValidatePerson() {
    log.info("Running: Should validate information from person: " + ToStringBuilder.reflectionToString(person));

    assertAll("person",
        () -> assertNotNull(person.getFirstName(), "Should get person's name"),
        () -> assertNotNull(person.getEmail(), "Should get person's email"),
        () -> assertTrue(person.getTelephoneNumber().matches(PHONE_REGEX), "Should have a valid telephone number")
        );
  }

  @Test
  @DisplayName("Should validate persons's company")
  void shouldValidatePersonCompany() {
    log.info("Running: Should validate information from person's company: " + ToStringBuilder.reflectionToString(person.getCompany()));

    Company company = person.getCompany();
    assertNotNull(company, () -> "should have a company");

    assertAll("company",
        () -> assertNotNull(company.getName(), "should get a name"),
        () -> assertTrue(company.getDomain().matches(DOMAIN_REGEX), "should have a valid domain"),
        () -> assertTrue(company.getVatIdentificationNumber().matches(VAT_REGEX), "should have a valid vat number")
        );
  }

}

This is the output:

INFO: Running: Should validate information from person: com.devskiller.jfairy.producer.person.Person@718121eb[address=175 Summer Place
San Francisco 58879,firstName=Brandon,middleName=,lastName=Le,email=le@gmail.com,username=brandonl,password=4boFv2ac,sex=MALE,telephoneNumber=488-324-672,dateOfBirth=1932-09-13,age=86,company=com.devskiller.jfairy.producer.company.Company@2f684683,companyEmail=brandon.le@buapel.biz,nationalIdentityCardNumber=404-92-0193,nationalIdentificationNumber=,passportNumber=lBplBWzhX,nationality=USA]

Certainly, you can build a person with specific criteria.

package com.jos.dem.jfairy.workshop;

import static org.junit.jupiter.api.Assertions.assertAll;
import static org.junit.jupiter.api.Assertions.assertTrue;

import org.apache.commons.lang3.builder.ToStringBuilder;

import com.devskiller.jfairy.Fairy;
import com.devskiller.jfairy.producer.person.Person;
import com.devskiller.jfairy.producer.person.PersonProperties;

import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.DisplayName;

import java.util.logging.Logger;

class PersonComposerTest {

  private static final Integer MIN_AGE=21;

  private Fairy fairy = Fairy.create();
  private Person adultMale = fairy.person(PersonProperties.male(), PersonProperties.minAge(MIN_AGE));

  private static final Logger log = Logger.getLogger(PersonComposerTest.class.getName());

  @Test
  @DisplayName("Should validate person")
  void shouldValidatePerson() {
    log.info("Running: Should validate information from person: " + ToStringBuilder.reflectionToString(adultMale));

    assertAll("adult",
        () -> assertTrue(adultMale.isMale(), "should be male"),
        () -> assertTrue(adultMale.getAge() >= MIN_AGE, "should be at least 21 years old")
        );
  }


}

To test the project:

gradle test

To browse the code go here, to download the code:

git clone https://github.com/josdem/jfairy-workshop.git

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