JUnit参数化测试执行失败：No public static parameters方法异常求助

问题详情 #

运行JUnit Parameterized测试时触发以下错误：

java.lang.Exception: No public static parameters method on class com.nyl.group.bpbilling.util.ParsingUtilTest
at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
at java.base/java.util.ArrayList$ArrayListSpliterator.tryAdvance(ArrayList.java:1602)
at java.base/java.util.stream.ReferencePipeline.forEachWithCancel(ReferencePipeline.java:129)
at java.base/java.util.stream.AbstractPipeline.copyIntoWithCancel(AbstractPipeline.java:527)
at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:513)

测试代码如下：

@RunWith(Parameterized.class)
public class ParsingUtilTest {
    
    @Test
    @Parameters
    public List<String[]> parameters() {
            return Arrays.asList(
                new String[]{"wrtier { type=file  }; reader { type=DB, query=update asdsadsad  }; processor { type = None }", "{wrtier={type=file}, reader={type=DB, query=update asdsadsad}, processor={type=None}}"},
                new String[]{"wrtier { type=file  };wrtier { type=file  }", "{wrtier={type=file}, wrtier_1={type=file}}"},
                new String[]{"", "{}"},
                new String[]{"{}", ""},
                new String[]{";wrtier { type=file  }", "{}"},
                new String[]{"{}", ";wrtier { type=file  }"},
                new String[]{"wrtier type=file}", "wrtier type=file}"},
                new String[]{"{w={t=f}}", "w{t=f}"}
            );
        }
    public void testParseStepSequenceInMapCnd1(String level, String expected ) throws Exception {
        CnfStep step = new CnfStep();
        step.setStepParams(level);
        assertEquals(expected, ParsingUtil.parseStepSequenceInMap( step.getStepParams() ).toString());
    }
}

解决方法 #

报错原因清晰：JUnit Parameterized要求提供测试参数的方法必须是public static，且不能加@Test注解。你的代码存在三个问题，修正即可：

• 给参数方法parameters()添加static修饰符
• 移除参数方法上的@Test注解（仅保留@Parameters）
• 给测试方法testParseStepSequenceInMapCnd1添加@Test注解，否则测试不会被执行

修正后的代码：

@RunWith(Parameterized.class)
public class ParsingUtilTest {
    
    @Parameters
    public static List<String[]> parameters() {
            return Arrays.asList(
                new String[]{"wrtier { type=file  }; reader { type=DB, query=update asdsadsad  }; processor { type = None }", "{wrtier={type=file}, reader={type=DB, query=update asdsadsad}, processor={type=None}}"},
                new String[]{"wrtier { type=file  };wrtier { type=file  }", "{wrtier={type=file}, wrtier_1={type=file}}"},
                new String[]{"", "{}"},
                new String[]{"{}", ""},
                new String[]{";wrtier { type=file  }", "{}"},
                new String[]{"{}", ";wrtier { type=file  }"},
                new String[]{"wrtier type=file}", "wrtier type=file}"},
                new String[]{"{w={t=f}}", "w{t=f}"}
            );
        }
    
    @Test
    public void testParseStepSequenceInMapCnd1(String level, String expected ) throws Exception {
        CnfStep step = new CnfStep();
        step.setStepParams(level);
        assertEquals(expected, ParsingUtil.parseStepSequenceInMap( step.getStepParams() ).toString());
    }
}

内容的提问来源于stack exchange，提问作者kanna