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For example, to test a Fibonacci function, write:
import static org.junit.Assert.assertEquals;
import java.util.Arrays;
import java.util.Collection;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;
@RunWith(Parameterized.class)
public class FibonacciTest {
@Parameters
public static Collection<Object[]> data() {
return Arrays.asList(new Object[][] {
{ 0, 0 }, { 1, 1 }, { 2, 1 }, { 3, 2 }, { 4, 3 }, { 5, 5 }, { 6, 8 }
});
}
private int fInput;
private int fExpected;
public FibonacciTest(int input, int expected) {
this.fInput = input;
this.fExpected = expected;
}
@Test
public void test() {
assertEquals(fExpected, Fibonacci.compute(fInput));
}
}
public class Fibonacci {
public static int compute(int n) {
int result = 0;
if (n <= 1) {
result = n;
} else {
result = compute(n - 1) + compute(n - 2);
}
return result;
}
}
@Parameters
method.Using @Parameter for Field injection instead of Constructor
import static org.junit.Assert.assertEquals;
import java.util.Arrays;
import java.util.Collection;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameter;
import org.junit.runners.Parameterized.Parameters;
@RunWith(Parameterized.class)
public class FibonacciTest {
@Parameters
public static Collection<Object[]> data() {
return Arrays.asList(new Object[][] {
{ 0, 0 }, { 1, 1 }, { 2, 1 }, { 3, 2 }, { 4, 3 }, { 5, 5 }, { 6, 8 }
});
}
@Parameter // first data value (0) is default
public /* NOT private */ int fInput;
@Parameter(1)
public /* NOT private */ int fExpected;
@Test
public void test() {
assertEquals(fExpected, Fibonacci.compute(fInput));
}
}
public class Fibonacci {
...
}
Tests with single parameter
@Parameters
public static Iterable<? extends Object> data() {
return Arrays.asList("first test", "second test");
}
@Parameters
public static Object[] data() {
return new Object[] { "first test", "second test" };
}
Identify Individual test cases
{index}
: the current parameter index{0}, {1}, …
: the first, second, and so on, parameter value. NOTE: single quotes'
should be escaped as two single quotes''
.
Example
import static org.junit.Assert.assertEquals;
import java.util.Arrays;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;
@RunWith(Parameterized.class)
public class FibonacciTest {
@Parameters(name = "{index}: fib({0})={1}")
public static Iterable<Object[]> data() {
return Arrays.asList(new Object[][] {
{ 0, 0 }, { 1, 1 }, { 2, 1 }, { 3, 2 }, { 4, 3 }, { 5, 5 }, { 6, 8 }
});
}
private int input;
private int expected;
public FibonacciTest(int input, int expected) {
this.input = input;
this.expected = expected;
}
@Test
public void test() {
assertEquals(expected, Fibonacci.compute(input));
}
}
public class Fibonacci {
...
}
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