Junit parameterized tests using file input

Question

I have a query about using parameterized tests for my unit testing of my APIs. Now instead of building an arraylist like

Arrays.asList(new Object[]{
   {1},         


        

Answer 1

Have a look at the junitparams project, especially this example. It will show you how to use a CSV file for parameter input. Here's a short example:

My test.csv file:

1, one
2, two
3, three

My test:

package com.stackoverflow.sourabh.example;

import static org.junit.Assert.assertTrue;
import junitparams.FileParameters;
import junitparams.JUnitParamsRunner;

import org.junit.Test;
import org.junit.runner.RunWith;

@RunWith(JUnitParamsRunner.class)
public class FileReadingParameterizedTest {

    @Test
    @FileParameters("src/test/resources/test.csv")
    public void testWithCSV(int number, String name) {
        assertTrue(name + " is not at least two", number >= 2);
    }

}

Obviously the first test will fail, producing the error message one is not at least two.

Answer 2

@RunWith(JUnitParamsRunner.class)
public class FileParamsTest {

    @Test
    @FileParameters("src/test/resources/test.csv")
    public void loadParamsFromFileWithIdentityMapper(int age, String name) {
        assertTrue(age > 0);
    }

}

JUnitParams has support for loading the data from a CSV file.

CSV File will contain

1,true
2,false

Answer 3

In Spring-boot Java framework, you can use the Value annotation conveniently within the class,

@Component
public class MyRunner implements CommandLineRunner {

@Value("classpath:thermopylae.txt") //Annotation
private Resource res; // res will hold that value the `txt` player

@Autowired
private CountWords countWords;

@Override
public void run(String... args) throws Exception {

    Map<String, Integer> words =  countWords.getWordsCount(res);

    for (String key : words.keySet()) {

        System.out.println(key + ": " + words.get(key));
       }
   }
}

Source