Got rid of javadoc warning, issue #548

ant-phase-compile.xml

@@ -7,10 +7,9 @@
       <entry key="checkstyle.compile.version" value="${mvn.project.version}"/>
       <entry key="checkstyle.compile.timestamp" type="date" value="now" pattern="E MMMM dd yyyy, HH:mm z"/>
     </propertyfile>
-
     <javadoc sourcefiles="src/main/java/com/puppycrawl/tools/checkstyle/api/TokenTypes.java"
              encoding="iso-8859-1"
-             source="1.5"
+             source="${java.version}"
              failonerror="yes">
       <classpath>
         <pathelement location="${mvn.project.build.outputDirectory}"/>

pom.xml

@@ -152,6 +152,7 @@
     <maven.site.plugin.version>3.4</maven.site.plugin.version>
     <tools.jar.version>1.7.0</tools.jar.version>
     <tools.jar.path>${java.home}/../lib/tools.jar</tools.jar.path>
+    <java.version>1.7</java.version>
   </properties>
 
   <dependencies>
@@ -277,8 +278,8 @@
         <artifactId>maven-compiler-plugin</artifactId>
         <version>2.3.2</version>
         <configuration>
-          <source>1.7</source>
-          <target>1.7</target>
+          <source>${java.version}</source>
+          <target>${java.version}</target>
         </configuration>
       </plugin>