Question

我有一个带构造函数的类，它得到如下输入：

public class Project {
    public Project(Parameter1 par1, Parameter2 par2 ...) {
    //here if one incoming parameters equals null - throw exception
    }
}

问题是如何测试在一次测试中针对不同参数抛出异常？类似的东西：

@Test
publci void testException() {
    Project project1 = new Project(null, par2 ....);//here it throws  exception and test is finished((((
//I want it to continue testing project2
    Project project2 = new Project(par1, null ...);
}

Answer 1

@Test
public void testException() {
    boolean exception1Thrown = false;
    try {
        Project project1 = new Project(null, par2 ....);
    }catch(Exception e){
        exception1Thrown = true;
    }
    assertTrue(exception1Thrown);

    boolean exception2Thrown = false;
    try {
        Project project2 = new Project(par1, null ...);
    }catch(Exception e){
        exception2Thrown = true;
    }
    assertTrue(exception2Thrown);

}

这只是其中几种方法之一。有关详情，请参阅this question

Answer 2

将Project1 = new Project(....和Project2 = new Project(.....保留在各自的try catch块中。通过第一个块抛出的异常不会阻止以后的代码部分运行。

Answer 3

你可以通过标志（shouldThrowException）作为测试参数之一。但更清洁的方法是进行两次测试。一个用于正确参数，一个用于错误参数。我会这样做：

import static org.assertj.core.api.Assertions.assertThatThrownBy;
import org.junit.runner.RunWith;
import com.googlecode.zohhak.api.Coercion;
import com.googlecode.zohhak.api.TestWith;
import com.googlecode.zohhak.api.runners.ZohhakRunner;

@RunWith(ZohhakRunner.class)
public class MyTest {

  @TestWith({
        "parameter1,      parameter2",
        "otherParameter1, otherParameter2" 
  })
  public void should_construct_project(Parameter parameter1, Parameter parameter2) {
    new Project(parameter1, parameter2);
  }

  @TestWith({
        "null,            parameter2",
        "otherParameter1, null",
        "badParameter1,   goodParameter2"
  })
  public void should_fail_constructing_project(Parameter parameter1, Parameter parameter2) {

    assertThatThrownBy(() -> new Project(parameter1, parameter2))
                                    .isInstanceOf(NullPointerException.class);          
  }

  @Coercion
  public Parameter toParameter(String input) {
    return new Parameter(...);
  }
}

如果您想测试所有可能的参数组合，那么数据提供者或理论可能会有用。

Answer 4

您可以使用https://github.com/Pragmatists/JUnitParams执行此操作：

假设您有一个Person对象，必须指定所有参数，然后您可以使用JUnitParams以这种方式进行测试：

@Test(expected = IllegalArgumentException.class)
    @Parameters(
    {", bloggs, joe.bloggs@ig.com",
    "joe, , joe.bloggs@ig.com,",
    "joe, bloggs, ,",
)
public void allParametersAreMandatory(String firstName, String lastName, String emailAddress)
{
   new Person(firstName, lastName, emailAddress);
}

带有不同参数的java测试构造函数

4 个答案: