Adding custom Suppress FindBugs class to make it JDK8 compatible (#502)

Adding Getter for the CanUpdate and the CoolOffPeriodInMillis

src/main/java/com/amazon/opendistro/elasticsearch/performanceanalyzer/decisionmaker/actions/CacheClearAction.java

@@ -19,6 +19,7 @@
 
 import com.amazon.opendistro.elasticsearch.performanceanalyzer.AppContext;
 import com.amazon.opendistro.elasticsearch.performanceanalyzer.rca.store.rca.cluster.NodeKey;
+import com.amazon.opendistro.elasticsearch.performanceanalyzer.util.SuppressFBWarnings;
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.google.gson.annotations.SerializedName;
@@ -27,7 +28,6 @@
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
-import org.graalvm.compiler.options.SuppressFBWarnings;
 
 public class CacheClearAction extends SuppressibleAction {
   public static final String NAME = "CacheClear";
@@ -131,10 +131,8 @@ public static class Summary {
     @SerializedName(value = IP)
     private String[] ip;
     @SerializedName(value = COOL_OFF_PERIOD)
-    @SuppressFBWarnings(value = "URF_UNREAD_FIELD", justification = "Used in Summary Serializing")
     private long coolOffPeriodInMillis;
     @SerializedName(value = CAN_UPDATE)
-    @SuppressFBWarnings(value = "URF_UNREAD_FIELD", justification = "Used in Summary Serializing")
     private boolean canUpdate;
 
     public Summary(final List<NodeKey> impactedNodes,
@@ -155,5 +153,13 @@ public String toJson() {
       Gson gson = new GsonBuilder().disableHtmlEscaping().create();
       return gson.toJson(this);
     }
+
+    public boolean getCanUpdate() {
+      return this.canUpdate;
+    }
+
+    public long getCoolOffPeriodInMillis() {
+      return this.coolOffPeriodInMillis;
+    }
   }
 }

src/main/java/com/amazon/opendistro/elasticsearch/performanceanalyzer/util/SuppressFBWarnings.java

@@ -0,0 +1,19 @@
+package com.amazon.opendistro.elasticsearch.performanceanalyzer.util;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+@Retention(RetentionPolicy.CLASS)
+public @interface SuppressFBWarnings {
+    /**
+     * The set of FindBugs warnings that are to be suppressed in
+     * annotated element. The value can be a bug category, kind or pattern.
+     *
+     */
+    String[] value() default {};
+
+    /**
+     * Optional documentation of the reason why the warning is suppressed
+     */
+    String justification() default "";
+}