add JMH sample

Author: rieckpil

spring-boot-example/pom.xml

@@ -301,7 +301,6 @@
       <groupId>org.openjdk.jmh</groupId>
       <artifactId>jmh-core</artifactId>
       <version>${jmh-core.version}</version>
-      <scope>test</scope>
     </dependency>
     <dependency>
       <groupId>org.openjdk.jmh</groupId>
@@ -412,6 +411,36 @@
           <format>html</format>
         </configuration>
       </plugin>
+
+      <plugin>
+        <artifactId>maven-dependency-plugin</artifactId>
+        <executions>
+          <execution>
+            <id>build-classpath</id>
+            <goals>
+              <goal>build-classpath</goal>
+            </goals>
+            <configuration>
+              <includeScope>runtime</includeScope>
+              <outputProperty>depClasspath</outputProperty>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>org.codehaus.mojo</groupId>
+        <artifactId>exec-maven-plugin</artifactId>
+        <version>3.0.0</version>
+        <configuration>
+          <mainClass>de.rieckpil.blog.jmh.StringConcatenationBenchmark</mainClass>
+          <systemProperties>
+            <systemProperty>
+              <key>java.class.path</key>
+              <value>${project.build.outputDirectory}${path.separator}${depClasspath}</value>
+            </systemProperty>
+          </systemProperties>
+        </configuration>
+      </plugin>
     </plugins>
   </build>
 </project>