Java 一个mock 工具/random

https://www.baeldung.com/java-easy-random

<dependency>
    <groupId>org.jeasy</groupId>
    <artifactId>easy-random-core</artifactId>
    <version>4.0.0</version>
</dependency>

@Test
void givenDefaultConfiguration_thenGenerateSingleObject() {
    EasyRandom generator = new EasyRandom();
    Person person = generator.nextObject(Person.class);

    assertNotNull(person.getAge());
    assertNotNull(person.getFirstName());
    assertNotNull(person.getLastName());
}

@Test
void givenDefaultConfiguration_thenGenerateObjectsList() {
    EasyRandom generator = new EasyRandom();
    List<Person> persons = generator.objects(Person.class, 5)
        .collect(Collectors.toList());

    assertEquals(5, persons.size());
}

@Test
void givenCustomConfiguration_thenGenerateSingleEmployee() {
    EasyRandomParameters parameters = new EasyRandomParameters();
    parameters.stringLengthRange(3, 3);
    parameters.collectionSizeRange(5, 5);
    parameters.excludeField(FieldPredicates.named("lastName").and(FieldPredicates.inClass(Employee.class)));
    parameters.excludeType(TypePredicates.inPackage("not.existing.pkg"));
    parameters.randomize(YearQuarter.class, new YearQuarterRandomizer());

    EasyRandom generator = new EasyRandom(parameters);
    Employee employee = generator.nextObject(Employee.class);

    assertEquals(3, employee.getFirstName().length());
    assertEquals(5, employee.getCoworkers().size());
    assertEquals(5, employee.getQuarterGrades().size());
    assertNotNull(employee.getDepartment());

    assertNull(employee.getLastName());

    for (YearQuarter key : employee.getQuarterGrades().keySet()) {
        assertEquals(key.getStartDate(), key.getEndDate().minusMonths(3L));
    }
}