Address the comments

Signed-off-by: Arpit Bandejiya <abandeji@amazon.com>

Author: alchemist51

server/src/main/java/org/opensearch/cluster/routing/allocation/AllocationConstraints.java

@@ -30,9 +30,9 @@ public class AllocationConstraints {
 
     public AllocationConstraints() {
         this.constraints = new HashMap<>();
-        this.constraints.putIfAbsent(INDEX_SHARD_PER_NODE_BREACH_CONSTRAINT_ID, new Constraint(isIndexShardsPerNodeBreached()));
-        this.constraints.putIfAbsent(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, new Constraint(isPerIndexPrimaryShardsPerNodeBreached()));
-        this.constraints.putIfAbsent(CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, new Constraint(isPrimaryShardsPerNodeBreached(0.0f)));
+        this.constraints.put(INDEX_SHARD_PER_NODE_BREACH_CONSTRAINT_ID, new Constraint(isIndexShardsPerNodeBreached()));
+        this.constraints.put(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, new Constraint(isPerIndexPrimaryShardsPerNodeBreached()));
+        this.constraints.put(CLUSTER_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, new Constraint(isPrimaryShardsPerNodeBreached(0.0f)));
     }
 
     public void updateAllocationConstraint(String constraint, boolean enable) {

server/src/main/java/org/opensearch/cluster/routing/allocation/RebalanceConstraints.java

@@ -31,8 +31,8 @@ public class RebalanceConstraints {
 
     public RebalanceConstraints(RebalanceParameter rebalanceParameter) {
         this.constraints = new HashMap<>();
-        this.constraints.putIfAbsent(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, new Constraint(isPerIndexPrimaryShardsPerNodeBreached()));
-        this.constraints.putIfAbsent(
+        this.constraints.put(INDEX_PRIMARY_SHARD_BALANCE_CONSTRAINT_ID, new Constraint(isPerIndexPrimaryShardsPerNodeBreached()));
+        this.constraints.put(
             CLUSTER_PRIMARY_SHARD_REBALANCE_CONSTRAINT_ID,
             new Constraint(isPrimaryShardsPerNodeBreached(rebalanceParameter.getPreferPrimaryBalanceBuffer()))
         );

server/src/main/java/org/opensearch/cluster/routing/allocation/allocator/BalancedShardsAllocator.java

@@ -182,7 +182,7 @@ public BalancedShardsAllocator(Settings settings, ClusterSettings clusterSetting
         setShardBalanceFactor(SHARD_BALANCE_FACTOR_SETTING.get(settings));
         setIndexBalanceFactor(INDEX_BALANCE_FACTOR_SETTING.get(settings));
         setPreferPrimaryShardRebalanceBuffer(PRIMARY_SHARD_REBALANCE_BUFFER.get(settings));
-        setWeightFunction();
+        updateWeightFunction();
         setThreshold(THRESHOLD_SETTING.get(settings));
         setPreferPrimaryShardBalance(PREFER_PRIMARY_SHARD_BALANCE.get(settings));
         setPreferPrimaryShardRebalance(PREFER_PRIMARY_SHARD_REBALANCE.get(settings));
@@ -232,20 +232,20 @@ private void setPreferPrimaryShardRebalanceBuffer(float preferPrimaryShardRebala
 
     private void updateIndexBalanceFactor(float indexBalanceFactor) {
         this.indexBalanceFactor = indexBalanceFactor;
-        setWeightFunction();
+        updateWeightFunction();
     }
 
     private void updateShardBalanceFactor(float shardBalanceFactor) {
         this.shardBalanceFactor = shardBalanceFactor;
-        setWeightFunction();
+        updateWeightFunction();
     }
 
     private void updatePreferPrimaryShardBalanceBuffer(float preferPrimaryShardBalanceBuffer) {
         this.preferPrimaryShardRebalanceBuffer = preferPrimaryShardBalanceBuffer;
-        setWeightFunction();
+        updateWeightFunction();
     }
 
-    private void setWeightFunction() {
+    private void updateWeightFunction() {
         weightFunction = new WeightFunction(this.indexBalanceFactor, this.shardBalanceFactor, this.preferPrimaryShardRebalanceBuffer);
     }