Use release flag

Author: ctron

pom.xml

@@ -1,5 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 
     <modelVersion>4.0.0</modelVersion>
 
@@ -70,6 +72,8 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+
+        <java.release>8</java.release>
         <java.source>1.8</java.source>
 
         <junit.jupiter.version>5.4.0</junit.jupiter.version>
@@ -169,8 +173,7 @@
                     <artifactId>maven-compiler-plugin</artifactId>
                     <version>3.8.0</version>
                     <configuration>
-                        <source>${java.source}</source>
-                        <target>${java.source}</target>
+                        <release>${java.release}</release>
                     </configuration>
                 </plugin>
 
@@ -220,9 +223,9 @@
                 </plugin>
 
                 <plugin>
-                  <groupId>org.apache.maven.plugins</groupId>
-                  <artifactId>maven-surefire-plugin</artifactId>
-                  <version>3.0.0-M3</version>
+                    <groupId>org.apache.maven.plugins</groupId>
+                    <artifactId>maven-surefire-plugin</artifactId>
+                    <version>3.0.0-M3</version>
                 </plugin>
 
                 <!-- others -->
@@ -275,6 +278,7 @@
                     </execution>
                 </executions>
             </plugin>
+
         </plugins>
 
     </build>