Convert all the internal assignment state objects to be ResourceAssignment. (#399)

This is to avoid unnecessary information being recorded or read.

Author: jiajunwang

helix-core/src/main/java/org/apache/helix/controller/rebalancer/waged/AssignmentMetadataStore.java

@@ -19,7 +19,7 @@
  * under the License.
  */
 
-import org.apache.helix.model.IdealState;
+import org.apache.helix.model.ResourceAssignment;
 
 import java.util.HashMap;
 import java.util.Map;
@@ -28,23 +28,23 @@
  * A placeholder before we have the real assignment metadata store.
  */
 public class AssignmentMetadataStore {
-  private Map<String, IdealState> _persistGlobalBaseline = new HashMap<>();
-  private Map<String, IdealState> _persistBestPossibleAssignment = new HashMap<>();
+  private Map<String, ResourceAssignment> _persistGlobalBaseline = new HashMap<>();
+  private Map<String, ResourceAssignment> _persistBestPossibleAssignment = new HashMap<>();
 
-  public Map<String, IdealState> getBaseline() {
+  public Map<String, ResourceAssignment> getBaseline() {
     return _persistGlobalBaseline;
   }
 
-  public void persistBaseline(Map<String, IdealState> globalBaseline) {
+  public void persistBaseline(Map<String, ResourceAssignment> globalBaseline) {
     // TODO clean up invalid items
     _persistGlobalBaseline = globalBaseline;
   }
 
-  public Map<String, IdealState> getBestPossibleAssignment() {
+  public Map<String, ResourceAssignment> getBestPossibleAssignment() {
     return _persistBestPossibleAssignment;
   }
 
-  public void persistBestPossibleAssignment(Map<String, IdealState> bestPossibleAssignment) {
+  public void persistBestPossibleAssignment(Map<String, ResourceAssignment> bestPossibleAssignment) {
     // TODO clean up invalid items
     _persistBestPossibleAssignment.putAll(bestPossibleAssignment);
   }

helix-core/src/main/java/org/apache/helix/controller/rebalancer/waged/ClusterDataProvider.java

@@ -21,7 +21,7 @@
 
 import org.apache.helix.controller.dataproviders.ResourceControllerDataProvider;
 import org.apache.helix.controller.rebalancer.waged.model.ClusterModel;
-import org.apache.helix.model.IdealState;
+import org.apache.helix.model.ResourceAssignment;
 
 import java.util.Map;
 import java.util.Set;
@@ -46,7 +46,8 @@ public class ClusterDataProvider {
    */
   protected static ClusterModel generateClusterModel(ResourceControllerDataProvider dataProvider,
       Set<String> activeInstances, Map<ClusterDataDetector.ChangeType, Set<String>> clusterChanges,
-      Map<String, IdealState> baselineAssignment, Map<String, IdealState> bestPossibleAssignment) {
+      Map<String, ResourceAssignment> baselineAssignment,
+      Map<String, ResourceAssignment> bestPossibleAssignment) {
     // TODO finish the implementation.
     return null;
   }

helix-core/src/main/java/org/apache/helix/controller/rebalancer/waged/RebalanceAlgorithm.java

@@ -21,7 +21,6 @@
 
 import org.apache.helix.controller.rebalancer.waged.constraints.HardConstraint;
 import org.apache.helix.controller.rebalancer.waged.model.ClusterModel;
-import org.apache.helix.model.IdealState;
 import org.apache.helix.model.ResourceAssignment;
 
 import java.util.Map;
@@ -39,7 +38,7 @@ public interface RebalanceAlgorithm {
    * @param clusterModel
    * @param failureReasons Return the failures <ResourceName, <FailureReason, Count>> that happen during the rebalance calculation.
    *                       If the map is null, no failure will be returned.
-   * @return A map <ResourceName, FailureReason> of the rebalanced resource assignments that are saved in the IdeaStates.
+   * @return A map of <ResourceName, ResourceAssignment>.
    */
   Map<String, ResourceAssignment> rebalance(ClusterModel clusterModel,
       Map<String, Map<HardConstraint.FailureReason, Integer>> failureReasons);

helix-core/src/main/java/org/apache/helix/controller/rebalancer/waged/constraints/ConstraintsRebalanceAlgorithm.java

@@ -21,7 +21,6 @@
 
 import org.apache.helix.controller.rebalancer.waged.RebalanceAlgorithm;
 import org.apache.helix.controller.rebalancer.waged.model.ClusterModel;
-import org.apache.helix.model.IdealState;
 import org.apache.helix.model.ResourceAssignment;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;