Generate Realistic Test Data in Java with JavaFaker

1. Introduction

The boss wants convincing demo data for a client presentation, and developers often find generating such data tedious. This article introduces a simple way to produce realistic fake data using JavaFaker.

2. JavaFaker

JavaFaker is a Java library designed to generate synthetic data for testing. Add the following Maven dependency to your project:

<dependency>
    <groupId>com.github.javafaker</groupId>
    <artifactId>javafaker</artifactId>
    <version>1.0.2</version>
</dependency>

The primary use case is to create mock test data, not to fabricate fraudulent information.

First, define a simple Java bean to hold user information:

/**
 * User info.
 */
@Data
public class UserInfo {
    /** Real name */
    private String realName;
    /** Mobile phone */
    private String cellPhone;
    /** University */
    private String universityName;
    /** City */
    private String city;
    /** Street address */
    private String street;
}

Instantiate a Faker object. For Chinese data: Faker fakerWithCN = new Faker(Locale.CHINA); For US data, change the locale: Faker fakerWithCN = new Faker(Locale.US); Generate ten mock user records using the faker:

for (int i = 0; i < 10; i++) {
    UserInfo userInfo = new UserInfo();
    userInfo.setRealName(fakerWithCN.name().fullName());
    userInfo.setCellPhone(fakerWithCN.phoneNumber().cellPhone());
    userInfo.setCity(fakerWithCN.address().city());
    userInfo.setStreet(fakerWithCN.address().streetAddress());
    userInfo.setUniversityName(fakerWithCN.university().name());
    System.out.println("userInfo = " + userInfo);
}

Resulting output looks like genuine data:

Using JavaFaker satisfies the boss's request while reducing the effort needed for test data preparation. Remember to use the generated data responsibly and not for dishonest purposes.