JarCastingPojofill 
This is a library to instantiate a POJO (Plain Old Java Object) filled with generated values. It is useful for building test double.
Getting Started
Dependencies:
// build.gradle
compile 'org.hidetake:pojofill:1.2.0'
<!-- pom.xml -->
<dependency>
<groupId>org.hidetake</groupId>
<artifactId>pojofill</artifactId>
<version>1.2.0</version>
<type>pom</type>
</dependency>
Let's take a look at the example.
// Person.java
@lombok.Data
public class Person {
private final int id;
private final String name;
private List<Pen> pens;
}
// Pen.java
@lombok.Data
public class Pen {
private final Color color;
public enum Color {
RED, YELLOW, GREEN, BLUE
}
}
// Main.java
import org.hidetake.pojofill.Pojofill;
public class Main {
public static void main(String[] args) {
Pojofill pojofill = new Pojofill();
Person person = pojofill.newInstanceOrNull(Person.class);
System.out.println(person);
}
}
Output will be following:
Person(id=123456, name=abcde, pens=[Pen(color=RED)])
Specification
Pojofill#newInstance() method accepts a type T and returns an instance wrapped with Optional<T>.
| Given type | Generated instance |
|---|---|
boolean |
true |
byte |
123 |
char |
a |
short |
12345 |
int |
123456 |
long |
1234567890 |
float |
1.23456 |
double |
1.23456 |
CharSequence (String) |
abcde |
enum |
the first constant |
Collection<E> |
a List with an E instantiated recursively (or empty List if it failed) |
Array of E |
an array with an E instantiated recursively (or empty array if it failed) |
| Class | an object |
If a class is given, the method tries to instantiate an object of the class. Members of the class are recursively initialized by the constructor and setters.
The method returns Optional.empty() if one of following is given:
void- Class without any public constructor
- Abstract class or interface
Custom value provider
Pojofill class accepts a custom value provider on the constructor.
class MyValueProvider extends DefaultValueProvider {
public CharSequence getCharSequence(InstantiationContext context) {
return "my custom string";
}
}
class Example {
public void main() {
Pojofill pojofill = new Pojofill();
pojofill.addInstantiator(new PrimitiveInstantiator(new MyValueProvider()));
}
}
An actual type of InstantiationContext should be determined by the context as follows:
| Context | Actual type |
|---|---|
Given in the method of Pojofill class |
TopLevel |
| Instantiating a constructor argument | ConstructorArgument |
| Instantiating a setter argument | SetterArgument |
| Instantiating an array element | ArrayElement |
| Instantiating an collection element | CollectionElement |
Logging
Pojofill depends on SLF4J. It describes error messages in the DEBUG level and trace messages in the TRACE level. Tested with Logback.
Contributions
This is an open source software licensed under the Apache License Version 2.0. Feel free to open issues or pull requests.
Copyright 2016-2017 Hidetake Iwata
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.