实际项目开发中,我们经常会使用@Value注解从配置文件中注入属性值,写单侧时,在不启动容器的条件下,如何对这种属性进行mock呢?对这种情况,Spring提供了一个很好的工具类ReflectionTestUtils来实现。
注入属性:
@Value("${prepaid.partner.id}")
private String merchantPartnerId;
对这个属性,在单测中可以这样mock:
ReflectionTestUtils.setField(targetObject, "merchantPartnerId", "123");
顾名思义,该工具类就是利用反射机制来实现的,底层源码如图所示:
public static Field findField(Class < ?>clazz, String name, Class < ?>type) {
Assert.notNull(clazz, "Class must not be null");
Assert.isTrue(name != null || type != null, "Either name or type of the field must be specified");
Class < ?>searchType = clazz;
while (Object.class != searchType && searchType != null) {
Field[] fields = getDeclaredFields(searchType);
for (Field field: fields) {
if ((name == null || name.equals(field.getName())) && (type == null || type.equals(field.getType()))) {
return field;
}
}
searchType = searchType.getSuperclass();
}
return null;
}
具体可参见:https://stackoverflow.com/questions/23162777/how-do-i-mock-an-autowired-value-field-in-spring-with-mockito |