Update dependencies, remove log4j2 dependency, instead rely on slf4 interface directly

Author: Stephen Powis

CHANGELOG.md

@@ -2,14 +2,38 @@
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
-## 2.1.1 (UNRELEASED)
+## 3.0.0 (UNRELEASED)
+
+#### Possible Breaking Dependency Change
+
+- Removed `org.apache.logging.log4j` dependency, instead relying on the org.slf4j logging interface/facade dependency explicitly.
+  - If your project was depending on this transitive dependency you may need to add it to your own project:
+
+  ```xml
+  <dependency>
+      <groupId>org.apache.logging.log4j</groupId>
+      <artifactId>log4j-api</artifactId>
+      <version>2.12.1</version>
+  </dependency>
+  <dependency>
+      <groupId>org.apache.logging.log4j</groupId>
+      <artifactId>log4j-core</artifactId>
+      <version>2.12.1</version>
+  </dependency>
+  <dependency>
+      <groupId>org.apache.logging.log4j</groupId>
+      <artifactId>log4j-slf4j-impl</artifactId>
+      <version>2.12.1</version>
+  </dependency>
+  ```
 
 #### Internal Dependency Updates
 - Checkstyle plugin from 8.19 -> 8.24
+- com.fasterxml.jackson.core from 2.9.9 -> 2.10.2
 - org.apache.logging.log4j from 2.11.2 -> 2.12.1
-- org.apache.httpcomponents from 4.5.8 -> 4.5.10
-- com.google.guava:guava from 27.1-jre -> 28.1-jre
-- org.eclipse.jetty:jetty-server (test dependency) from 9.4.17.v20190418 -> 9.4.20.v20190813
+- org.apache.httpcomponents from 4.5.8 -> 4.5.11
+- com.google.guava:guava from 27.1-jre -> 28.2-jre
+- org.eclipse.jetty:jetty-server (test dependency) from 9.4.17.v20190418 -> 9.4.27.v20200227
 - org.mockito:mockito-core (test dependency) from 2.27.0 -> 2.28.2
 
 ## 2.1.0 (06/26/2019)

pom.xml

@@ -47,13 +47,13 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 
         <!-- guava version -->
-        <guava.version>28.1-jre</guava.version>
+        <guava.version>28.2-jre</guava.version>
 
         <!-- Http Components version -->
-        <http-components.version>4.5.10</http-components.version>
+        <http-components.version>4.5.11</http-components.version>
 
         <!-- Jackson version -->
-        <jackson.version>2.9.9</jackson.version>
+        <jackson.version>2.10.2</jackson.version>
 
         <!-- Define which version of junit you'll be running -->
         <junit.version>4.12</junit.version>
@@ -65,6 +65,7 @@
 
         <!-- Log4J Version -->
         <log4j2.version>2.12.1</log4j2.version>
+        <slf4j.version>1.7.30</slf4j.version>
 
         <!-- test toggling -->
         <skipTests>false</skipTests>
@@ -103,21 +104,11 @@
             <version>${jackson.version}</version>
         </dependency>
 
-        <!-- Logging -->
+        <!-- Logging Interface -->
         <dependency>
-            <groupId>org.apache.logging.log4j</groupId>
-            <artifactId>log4j-api</artifactId>
-            <version>${log4j2.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>org.apache.logging.log4j</groupId>
-            <artifactId>log4j-core</artifactId>
-            <version>${log4j2.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>org.apache.logging.log4j</groupId>
-            <artifactId>log4j-slf4j-impl</artifactId>
-            <version>${log4j2.version}</version>
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-api</artifactId>
+            <version>${slf4j.version}</version>
         </dependency>
 
         <!-- Testing Tools -->
@@ -165,7 +156,27 @@
         <dependency>
             <groupId>org.eclipse.jetty</groupId>
             <artifactId>jetty-server</artifactId>
-            <version>9.4.20.v20190813</version>
+            <version>9.4.27.v20200227</version>
+            <scope>test</scope>
+        </dependency>
+
+        <!-- Logging in tests -->
+        <dependency>
+            <groupId>org.apache.logging.log4j</groupId>
+            <artifactId>log4j-api</artifactId>
+            <version>${log4j2.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.logging.log4j</groupId>
+            <artifactId>log4j-core</artifactId>
+            <version>${log4j2.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.logging.log4j</groupId>
+            <artifactId>log4j-slf4j-impl</artifactId>
+            <version>${log4j2.version}</version>
             <scope>test</scope>
         </dependency>
     </dependencies>