test: Add spotbugs and checkstyle maven plugins for Travis CI (#496)

Author: thatfiredev

Makefile

@@ -7,7 +7,7 @@ install:
 	cp target/sendgrid-java-$(VERSION)-shaded.jar sendgrid-java.jar
 
 test:
-	mvn test
+	mvn test spotbugs:spotbugs checkstyle:check -Dcheckstyle.config.location=google_checks.xml
 
 test-integ: test
 

pom.xml

@@ -259,6 +259,18 @@
           </execution>
         </executions>
       </plugin>
+      <plugin>
+        <groupId>com.github.spotbugs</groupId>
+        <artifactId>spotbugs-maven-plugin</artifactId>
+        <version>4.0.4</version>
+        <dependencies>
+          <dependency>
+            <groupId>com.github.spotbugs</groupId>
+            <artifactId>spotbugs</artifactId>
+            <version>4.0.4</version>
+          </dependency>
+        </dependencies>
+      </plugin>
     </plugins>
   </build>
   <developers>
@@ -309,4 +321,13 @@
       <version>1.66</version>
     </dependency>
   </dependencies>
-</project>
+  <reporting>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-checkstyle-plugin</artifactId>
+        <version>3.0.0</version>
+      </plugin>
+    </plugins>
+  </reporting>
+</project>