The method is() is undefined for the type in UnitTest Controller with Mockito - maven

Question

i'm newbie with the Spring boot. And the UnitTest with Controller drive me crazy
I have file pom.xml like this:
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.5.2</version>
<relativePath /> <!-- lookup parent from repository -->
</parent>
<groupId>com.nashtech</groupId>
<artifactId>MyBikeShop</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>MyBikeShop</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
<version>2.5.2</version>
</dependency>
<dependency>
<groupId>org.postgresql</groupId>
<artifactId>postgresql</artifactId>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-core</artifactId>
<version>5.4.32.Final</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.6.1</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt</artifactId>
<version>0.9.1</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-validation</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.security</groupId>
<artifactId>spring-security-test</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springdoc/springdoc-openapi-ui -->
<dependency>
<groupId>org.springdoc</groupId>
<artifactId>springdoc-openapi-ui</artifactId>
<version>1.5.9</version>
</dependency>
<!-- Junit 5 -->
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-api</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-engine</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.platform</groupId>
<artifactId>junit-platform-launcher</artifactId>
<scope>test</scope>
</dependency>
<!-- Mockito extention -->
<dependency>
<groupId>org.mockito</groupId>
<artifactId>mockito-junit-jupiter</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
And when i make a ControllerTest, it can define method is
I tried to import as many as i can find but it still not work. I had delete spring-boot-test-autoconfigure folder but still nothing

Answer 1

You need to import the is() method for it to be available for use in your class, add at the top of your file:
import static org.hamcrest.CoreMatchers.is;
You might alos need to add Hamcrest Core to your Maven dependency list.
<dependency>
<groupId>org.hamcrest</groupId>
<artifactId>hamcrest-core</artifactId>
<version>todo.x.y.z</version>
<scope>test</scope>
</dependency>

Answer 2

I found a useful way to did it
.andExpect(MockMvcResultMatchers.jsonPath("$.size()", Matchers.is(listOrder.size())));
But when i perfom like this:
MvcResult result = mockMvc.perform(MockMvcRequestBuilders.post("/api/order")
.content(ow.writeValueAsString(orderEntity))
.contentType(MediaType.APPLICATION_JSON)
.characterEncoding("UTF-8")
.accept(MediaType.APPLICATION_JSON).andReturn();
result.getResponse().getContentAsString()
is a empty String. I dont know why