YARN-7410. Cleanup FixedValueResource to avoid dependency to ResourceUtils. Contributed by Wangda Tan.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/java/org/apache/hadoop/yarn/api/records/Resource.java

@@ -364,7 +364,7 @@ public abstract class Resource implements Comparable<Resource> {
     }
   }
 
-  private void throwExceptionWhenArrayOutOfBound(int index) {
+  protected void throwExceptionWhenArrayOutOfBound(int index) {
     String exceptionMsg = String.format(
         "Trying to access ResourceInformation for given index=%d. "
             + "Acceptable index range is [0,%d), please check double check "

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/java/org/apache/hadoop/yarn/util/resource/ResourceUtils.java

@@ -267,6 +267,7 @@ public class ResourceUtils {
     updateKnownResources();
     updateResourceTypeIndex();
     initializedResources = true;
+    numKnownResourceTypes = resourceTypes.size();
   }
 
   private static void updateKnownResources() {

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/util/resource/Resources.java

@@ -118,6 +118,65 @@ public class Resources {
       throw new RuntimeException(name + " cannot be modified!");
     }
 
+    /*
+     *  FixedValueResource cannot be updated when any resource types refresh
+     *  by using approach introduced by YARN-7307 and do operations like
+     *  Resources.compare(resource_x, Resources.none()) will throw exceptions.
+     *
+     *  That's why we do reinitialize resource maps for following methods.
+     */
+
+    @Override
+    public ResourceInformation getResourceInformation(int index)
+        throws ResourceNotFoundException {
+      ResourceInformation ri = null;
+      try {
+        ri = super.getResourceInformation(index);
+      } catch (ResourceNotFoundException e) {
+        // Retry once to reinitialize resource information.
+        initResourceMap();
+        try {
+          return super.getResourceInformation(index);
+        } catch (ResourceNotFoundException ee) {
+          throwExceptionWhenArrayOutOfBound(index);
+        }
+      }
+      return ri;
+    }
+
+    @Override
+    public ResourceInformation getResourceInformation(String resource)
+        throws ResourceNotFoundException {
+      ResourceInformation ri;
+      try {
+        ri = super.getResourceInformation(resource);
+      } catch (ResourceNotFoundException e) {
+        // Retry once to reinitialize resource information.
+        initResourceMap();
+        try {
+          return super.getResourceInformation(resource);
+        } catch (ResourceNotFoundException ee) {
+          throw ee;
+        }
+      }
+      return ri;
+    }
+
+    @Override
+    public ResourceInformation[] getResources() {
+      if (resources.length != ResourceUtils.getNumberOfKnownResourceTypes()) {
+        // Retry once to reinitialize resource information.
+        initResourceMap();
+        if (resources.length != ResourceUtils.getNumberOfKnownResourceTypes()) {
+          throw new ResourceNotFoundException("Failed to reinitialize "
+              + "FixedValueResource to get number of resource types same "
+              + "as configured");
+        }
+      }
+
+      return resources;
+    }
+
     private void initResourceMap() {
       ResourceInformation[] types = ResourceUtils.getResourceTypesArray();
       if (types != null) {