moved to java 8

Author: wumpz

.travis.yml

@@ -1,7 +1,7 @@
 language: java
 jdk:
-  - openjdk7
-  - oraclejdk8
+  - openjdk8
+  - openjdk11
 
 after_success:
   - mvn clean cobertura:cobertura coveralls:report

pom.xml

@@ -87,8 +87,8 @@
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.7.0</version>
                 <configuration>
-                    <source>1.7</source>
-                    <target>1.7</target>
+                    <source>1.8</source>
+                    <target>1.8</target>
                     <showWarnings>true</showWarnings>
                     <encoding>${project.build.sourceEncoding}</encoding>
                 </configuration>
@@ -353,7 +353,7 @@
                     <plugin>
                         <groupId>org.apache.maven.plugins</groupId>
                         <artifactId>maven-checkstyle-plugin</artifactId>
-                        <version>2.17</version>
+                        <version>3.1.0</version>
                         <executions>
                             <execution>
                                 <id>verify-style</id>
@@ -366,7 +366,7 @@
                         <configuration>
                             <logViolationsToConsole>true</logViolationsToConsole>
                             <includeTestSourceDirectory>true</includeTestSourceDirectory>
-                            <sourceDirectory>${project.build.sourceDirectory}</sourceDirectory>
+                            <sourceDirectories>${project.build.sourceDirectory}</sourceDirectories>
                             <checkstyleRules>
                                 <module name="Checker">
                                     <module name="SuppressWarningsFilter" />
@@ -405,7 +405,7 @@
                             <dependency>
                                 <groupId>com.puppycrawl.tools</groupId>
                                 <artifactId>checkstyle</artifactId>
-                                <version>6.19</version>
+                                <version>8.22</version>
                             </dependency>
                         </dependencies>
                     </plugin>