```java
public class MethClazzTest {
@
Test public void sayHello() {
new MethClazz().sayHello();
}
}
```
```
$ mvn test
[INFO] Scanning for projects...
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Build Order:
[INFO]
[INFO] unit-testing [pom]
[INFO] test-module [jar]
[INFO]
[INFO] ----------------------< org.example:unit-testing >----------------------
[INFO] Building unit-testing 1.0-SNAPSHOT [1/2]
[INFO] --------------------------------[ pom ]---------------------------------
[INFO]
[INFO] ----------------------< org.example:test-module >-----------------------
[INFO] Building test-module 1.0-SNAPSHOT [2/2]
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ test-module ---
[WARNING] Using platform encoding (GBK actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] Copying 0 resource
[INFO]
[INFO] --- maven-compiler-plugin:3.8.0:compile (default-compile) @ test-module ---
[INFO] Not compiling main sources
[INFO]
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) @ test-module ---
[WARNING] Using platform encoding (GBK actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory E:\projects\unit-testing\test-module\src\test\resources
[INFO]
[INFO] --- maven-compiler-plugin:3.8.0:testCompile (default-testCompile) @ test-module ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding GBK, i.e. build is platform dependent!
[INFO] Compiling 1 source file to E:\projects\unit-testing\test-module\target\test-classes
[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR :
[INFO] -------------------------------------------------------------
[ERROR] /E:/projects/unit-testing/test-module/src/test/java/org/example/d1/MethClazzTest.java:[14,13] 找不到符号
符号: 类 MethClazz
位置: 类 org.example.d1.MethClazzTest
[INFO] 1 error
[INFO] -------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO]
[INFO] unit-testing 1.0-SNAPSHOT .......................... SUCCESS [ 0.040 s]
[INFO] test-module 1.0-SNAPSHOT ........................... FAILURE [ 3.981 s]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 4.484 s
[INFO] Finished at: 2021-08-19T20:03:02+08:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.8.0:testCompile (default-testCompile) on project test-module: Compilation failure
[ERROR] /E:/projects/unit-testing/test-module/src/test/java/org/example/d1/MethClazzTest.java:[14,13] 找不到符号
[ERROR] 符号: 类 MethClazz
[ERROR] 位置: 类 org.example.d1.MethClazzTest
[ERROR]
[ERROR] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1]
http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException[ERROR]
[ERROR] After correcting the problems, you can resume the build with the command
[ERROR] mvn <goals> -rf :test-module
```