Java 如何用 Hamcrest 断言某些东西是空的？
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How to assertThat something is null with Hamcrest?
提问by user2811419
How would I assertThatsomething is null?
我怎么会有assertThat东西null？
for example
例如
assertThat(attr.getValue(), is(""));
But I get an error saying that I cannot have nullin is(null).
但是我收到一个错误，说我不能null在is(null).
采纳答案by Rohit Jain
You can use IsNull.nullValue()method:
您可以使用IsNull.nullValue()方法：
import static org.hamcrest.Matchers.is;
import static org.hamcrest.Matchers.nullValue;
assertThat(attr.getValue(), is(nullValue()));
回答by Chetya
why not use assertNull(object)/ assertNotNull(object)?
为什么不使用assertNull(object)/ assertNotNull(object)？
回答by blackpanther
Use the following (from Hamcrest):
使用以下内容（来自 Hamcrest）：
assertThat(attr.getValue(), is(nullValue()));
In Kotlin isis reserved so use:
在 Kotlin 中is是保留的所以使用：
assertThat(attr.getValue(), `is`(nullValue()));
回答by Sajan Chandran
If you want to hamcrest, you can do
如果你愿意hamcrest，你可以
import static org.hamcrest.Matchers.nullValue;
assertThat(attr.getValue(), is(nullValue()));
In Junityou can do
在Junit你可以做
import static junit.framework.Assert.assertNull;
assertNull(object);
