updated POM to force use of Java version 8

code_size/pom.xml

@@ -12,6 +12,15 @@
   </properties>
   <build>
     <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.8.1</version>
+                <configuration>
+                    <source>8</source>
+                    <target>8</target>
+                </configuration>
+            </plugin>
       <plugin>
 	<groupId>org.apache.maven.plugins</groupId>
 	<artifactId>maven-jar-plugin</artifactId>