Question

我是模拟Junit测试的新手。这是我要测试的主要课程： import java.math.BigInteger; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import org.apache.commons.lang.StringUtils; import org.apache.log4j.Logger; import org.springframework.stereotype.Component;

@Component
public class IlinqChecksumCalculator {

    private static Logger DATA_LOADER_CHECKSUM_CALCULATOR_LOGGER = Logger.getLogger(IlinqChecksumCalculator.class);

    public String calculateCheckSum(String rfsdata) throws IOException {

        System.out.println(rfsdata);
        String checkSumValue = null;
        if (StringUtils.isNotBlank(rfsdata)) {
            try {
                // Create MessageDigest object for MD5
                MessageDigest digest = MessageDigest.getInstance("MD5");

                // Update input string in message digest
                digest.update(rfsdata.getBytes(), 0, rfsdata.getBytes().length);

                // Converts message digest value in base 16 (hex)
                checkSumValue = new BigInteger(1, digest.digest()).toString(16);

            } catch (NoSuchAlgorithmException exception) {
                DATA_LOADER_CHECKSUM_CALCULATOR_LOGGER.error(
                        "Error in determineInputCheckSum() method during calculation of checksum for Input JSON String for ",
                        exception);
            }
        }
        System.out.println("Final checksum value is:" + checkSumValue);
        return checkSumValue;
    }

}

这是我的测试班：

import static org.junit.Assert.assertEquals;
import static org.mockito.Mockito.when;

import java.io.IOException;

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.MockitoAnnotations;
import org.mockito.runners.MockitoJUnitRunner;
@RunWith(MockitoJUnitRunner.class)
public class IlinqChecksumCalculatorTest {

    private IlinqChecksumCalculator ilinqCheckSum;

    @Before
    public void setUp() throws Throwable {

        MockitoAnnotations.initMocks(this);
    }

    @Test
    public void testCheckSum() throws IOException {

        when(ilinqCheckSum.calculateCheckSum("abcde")).thenReturn("defgh");

        assertEquals("defgh", ilinqCheckSum.calculateCheckSum("abcde"));

    }
}

我收到空指针异常。

Answer 1

回答你的问题：要将ilinqCheckSum作为模拟处理，你应该用@Mock注释它。但在这里你不应该使用mockito！你想测试IlinqChecksumCalculator而不是模拟！您应该创建它的真实实例，并在必要时将依赖关系注入模拟。

Answer 2

通过模拟calculateCheckSum方法，您不会覆盖单元测试中的任何代码。我想你不应该在这里使用Mock。尝试以下测试方法。

 public void testCheckSum() throws IOException {

       String result =  ilinqCheckSum.calculateCheckSum("abcde")
        assertNotNull(result );

    }

执行mockito单元测试时出现NullPointerException

2 个答案: