Add Eclipse Checkstyle Plugin support

Update the Eclipse plugin to optionally support Eclipse Checkstyle.

Closes gh-82

Author: philwebb

pom.xml

@@ -32,6 +32,7 @@
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<java.version>1.8</java.version>
 		<eclipse.repository>https://download.eclipse.org/releases/2019-03/201903201000</eclipse.repository>
+		<eclipse.checkstyle.repository>https://dl.bintray.com/eclipse-cs/eclipse-cs/8.18.0</eclipse.checkstyle.repository>
 		<tycho.disableP2Mirrors>true</tycho.disableP2Mirrors>
 		<ant.version>1.8.1</ant.version>
 		<ant-contrib.version>1.0b3</ant-contrib.version>
@@ -590,6 +591,11 @@
 			<layout>p2</layout>
 			<url>${eclipse.repository}</url>
 		</repository>
+		<repository>
+			<id>eclipse-checkstyle</id>
+			<layout>p2</layout>
+			<url>${eclipse.checkstyle.repository}</url>
+		</repository>
 	</repositories>
 	<modules>
 		<module>spring-javaformat</module>

spring-javaformat-eclipse/io.spring.javaformat.eclipse/META-INF/MANIFEST.MF

@@ -15,8 +15,10 @@ Require-Bundle: org.eclipse.ui,
  org.eclipse.m2e.core;resolution:=optional,
  org.eclipse.m2e.maven.runtime;resolution:=optional,
  org.eclipse.buildship.core;resolution:=optional,
+ net.sf.eclipsecs.core;bundle-version="8.18.0";resolution:=optional,
  org.slf4j.api;bundle-version="1.7.0"
 Bundle-ClassPath: .,
  lib/spring-javaformat-formatter-eclipse.jar,
- lib/spring-javaformat-formatter.jar
+ lib/spring-javaformat-formatter.jar,
+ lib/spring-javaformat-checkstyle.jar
 Bundle-ActivationPolicy: lazy

spring-javaformat-eclipse/io.spring.javaformat.eclipse/build.properties

@@ -4,5 +4,6 @@ bin.includes = META-INF/,\
                plugin.xml,\
                lifecycle-mapping-metadata.xml,\
                lib/spring-javaformat-formatter-eclipse.jar,\
-               lib/spring-javaformat-formatter.jar
+               lib/spring-javaformat-formatter.jar,
+               lib/spring-javaformat-checkstyle.jar
 

spring-javaformat-eclipse/io.spring.javaformat.eclipse/plugin.xml

@@ -25,4 +25,16 @@
           class="io.spring.javaformat.eclipse.Startup">
     </startup>
  </extension>
+ <extension
+       point="net.sf.eclipsecs.core.checkstyleAddonProvider">
+ </extension>
+ <extension
+       id="id2"
+       point="net.sf.eclipsecs.core.configurations">
+    <check-configuration
+          description="Spring Build-in configuration"
+          location="io/spring/javaformat/checkstyle/checkstyle.xml"
+          name="Spring Builtin Checks">
+    </check-configuration>
+ </extension>
 </plugin>

spring-javaformat-eclipse/io.spring.javaformat.eclipse/pom.xml

@@ -22,5 +22,11 @@
 			<scope>runtime</scope>
 			<version>${project.version}</version>
 		</dependency>
+		<dependency>
+			<groupId>io.spring.javaformat</groupId>
+			<artifactId>spring-javaformat-checkstyle</artifactId>
+			<scope>runtime</scope>
+			<version>${project.version}</version>
+		</dependency>
 	</dependencies>
 </project>