Spring错误——Test class should have exactly one public constructor

背景：Spring 构建单元测试

错误

java.lang.Exception: Test class should have exactly one public constructor

    at org.junit.runners.BlockJUnit4ClassRunner.validateOnlyOneConstructor(BlockJUnit4ClassRunner.java:131)
    at org.junit.runners.BlockJUnit4ClassRunner.validateConstructor(BlockJUnit4ClassRunner.java:120)
    at org.junit.runners.BlockJUnit4ClassRunner.collectInitializationErrors(BlockJUnit4ClassRunner.java:101)
    at org.junit.runners.ParentRunner.validate(ParentRunner.java:344)
    at org.junit.runners.ParentRunner.<init>(ParentRunner.java:74)
    at org.junit.runners.BlockJUnit4ClassRunner.<init>(BlockJUnit4ClassRunner.java:55)
    at org.junit.internal.builders.JUnit4Builder.runnerForClass(JUnit4Builder.java:13)

错误原因：在Junit测试类中必须声明一个public 构造函数。我的测试类没有声明public，默认为default 。

public class TestBeanScope extends UnitTestBase {

    TestBeanScope(){
        super("classpath*:spring-scope.xml");
    }

    @Test
    public void  TestSingleton(){
        for (int i=0;i<3;i++){
            BeanScope beanScope = (BeanScope)super.getBean("beanScope");
            beanScope.say("test");
        }
    }
}

解决办法：构建一个公有构造函数即可

public class TestBeanScope extends UnitTestBase {

    public TestBeanScope(){
        super("classpath*:spring-scope.xml");
    }

    @Test
    public void  TestSingleton(){
        for (int i=0;i<3;i++){
            BeanScope beanScope = (BeanScope)super.getBean("beanScope");
            beanScope.say("test");
        }
    }
}