plugin cleanup

undertow/pom.xml

@@ -1,7 +1,7 @@
 <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/maven-v4_0_0.xsd">
     <modelVersion>4.0.0</modelVersion>
-    
+
     <groupId>com.baeldung.undertow</groupId>
     <artifactId>undertow</artifactId>
     <packaging>jar</packaging>
@@ -29,6 +29,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-shade-plugin</artifactId>
+                <version>${maven-shade-plugin.version}</version>
                 <executions>
                     <execution>
                         <phase>package</phase>
@@ -41,6 +42,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-jar-plugin</artifactId>
+                <version>${maven-jar-plugin.version}</version>
                 <configuration>
                     <archive>
                         <manifest>
@@ -54,6 +56,8 @@
 
     <properties>
         <undertow-servlet.version>1.4.18.Final</undertow-servlet.version>
+        <maven-shade-plugin.version>2.4.3</maven-shade-plugin.version>
+        <maven-jar-plugin.version>3.0.2</maven-jar-plugin.version>
     </properties>
 
 </project>