[Java] Upgrade checkstyle plugin (#4375)

java/api/src/main/java/org/ray/api/RayActor.java

@@ -4,6 +4,7 @@ import org.ray.api.id.UniqueId;
 
 /**
  * A handle to an actor.
+ *
  * @param <T> The type of the concrete actor class.
  */
 public interface RayActor<T> {

java/api/src/main/java/org/ray/api/WaitResult.java

@@ -1,6 +1,5 @@
 package org.ray.api;
 
-
 import java.util.List;
 
 /**

java/checkstyle-suppressions.xml

@@ -5,6 +5,7 @@
 <suppressions>
   <suppress checks="OperatorWrap" files=".*" />
   <suppress checks="JavadocParagraph" files=".*" />
+  <suppress checks="SummaryJavadoc" files=".*" />
   <suppress checks="MemberNameCheck" files="PathConfig.java"/>
   <suppress checks="MemberNameCheck" files="RayParameters.java"/>
   <suppress checks="AbbreviationAsWordInNameCheck" files="RayParameters.java"/>

java/pom.xml

@@ -217,14 +217,7 @@
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-checkstyle-plugin</artifactId>
-          <version>2.17</version>
-          <dependencies>
-            <dependency>
-              <groupId>com.puppycrawl.tools</groupId>
-              <artifactId>checkstyle</artifactId>
-              <version>6.19</version>
-            </dependency>
-          </dependencies>
+          <version>3.0.0</version>
           <executions>
             <execution>
               <id>validate</id>
@@ -239,13 +232,11 @@
             <suppressionsLocation>checkstyle-suppressions.xml</suppressionsLocation>
             <encoding>UTF-8</encoding>
             <consoleOutput>true</consoleOutput>
-            <failsOnError>false</failsOnError>
+            <failsOnError>true</failsOnError>
             <failOnViolation>true</failOnViolation>
             <violationSeverity>warning</violationSeverity>
             <format>xml</format>
-            <format>html</format>
-            <outputFile>${project.build.directory}/checkstyle-errors.xml
-            </outputFile>
+            <outputFile>${project.build.directory}/checkstyle-errors.xml</outputFile>
             <linkXRef>false</linkXRef>
           </configuration>
         </plugin>

java/runtime/src/main/java/org/ray/runtime/config/RayConfig.java

@@ -1,13 +1,11 @@
 package org.ray.runtime.config;
 
-
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 import com.typesafe.config.Config;
 import com.typesafe.config.ConfigException;
 import com.typesafe.config.ConfigFactory;
 import com.typesafe.config.ConfigValue;
-
 import java.io.File;
 import java.util.ArrayList;
 import java.util.List;