Merge branch '2.x' into Spotless_Backport_6_pt2

Signed-off-by: Mitchell Gale <Mitchell.gale@improving.com>

core/build.gradle

@@ -33,8 +33,8 @@ repositories {
     mavenCentral()
 }
 
-checkstyleTest.ignoreFailures = true
 checkstyleMain.ignoreFailures = true
+checkstyleTest.ignoreFailures = true
 
 dependencies {
     api group: 'com.google.guava', name: 'guava', version: '32.0.1-jre'

core/src/main/java/org/opensearch/sql/executor/ExecutionEngine.java

@@ -20,8 +20,8 @@
 public interface ExecutionEngine {
 
   /**
-   * Execute physical plan and call back response listener. Todo. deprecated this interface after
-   * finalize {@link ExecutionContext}.
+   * Execute physical plan and call back response listener.<br>
+   * Todo. deprecated this interface after finalize {@link ExecutionContext}.
    *
    * @param plan executable physical plan
    * @param listener response listener

core/src/main/java/org/opensearch/sql/executor/QueryManager.java

@@ -11,8 +11,8 @@
 import org.opensearch.sql.executor.execution.AbstractPlan;
 
 /**
- * QueryManager is the high-level interface of core engine. Frontend submit {@link AbstractPlan} to
- * QueryManager.
+ * QueryManager is the high-level interface of core engine. Frontend submit an {@link AbstractPlan}
+ * to QueryManager.
  */
 public interface QueryManager {
 

core/src/main/java/org/opensearch/sql/executor/QueryService.java

@@ -29,8 +29,8 @@ public class QueryService {
   private final Planner planner;
 
   /**
-   * Execute the {@link UnresolvedPlan}, using {@link ResponseListener} to get response. Todo.
-   * deprecated this interface after finalize {@link PlanContext}.
+   * Execute the {@link UnresolvedPlan}, using {@link ResponseListener} to get response.<br>
+   * Todo. deprecated this interface after finalize {@link PlanContext}.
    *
    * @param plan {@link UnresolvedPlan}
    * @param listener {@link ResponseListener}
@@ -46,7 +46,8 @@ public void execute(
 
   /**
    * Execute the {@link UnresolvedPlan}, with {@link PlanContext} and using {@link ResponseListener}
-   * to get response. Todo. Pass split from PlanContext to ExecutionEngine in following PR.
+   * to get response.<br>
+   * Todo. Pass split from PlanContext to ExecutionEngine in following PR.
    *
    * @param plan {@link LogicalPlan}
    * @param planContext {@link PlanContext}

core/src/main/java/org/opensearch/sql/executor/execution/StreamingQueryPlan.java

@@ -72,8 +72,9 @@ interface ExecutionStrategy {
   }
 
   /**
-   * execute task with fixed interval. if task run time < interval, trigger next task on next
-   * interval. if task run time >= interval, trigger next task immediately.
+   * execute task with fixed interval.<br>
+   * if task run time < interval, trigger next task on next interval.<br>
+   * if task run time >= interval, trigger next task immediately.
    */
   @RequiredArgsConstructor
   public static class IntervalTriggerExecution implements ExecutionStrategy {

core/src/main/java/org/opensearch/sql/executor/pagination/CanPaginateVisitor.java

@@ -41,16 +41,27 @@
 import org.opensearch.sql.expression.function.BuiltinFunctionName;
 
 /**
- * Use this unresolved plan visitor to check if a plan can be serialized by PaginatedPlanCache. If
+ * Use this unresolved plan visitor to check if a plan can be serialized by PaginatedPlanCache.<br>
+ * If
  *
  * <pre>plan.accept(new CanPaginateVisitor(...))</pre>
  *
- * returns <em>true</em>, then PaginatedPlanCache.convertToCursor will succeed. Otherwise, it will
- * fail. The purpose of this visitor is to activate legacy engine fallback mechanism. Currently, V2
- * engine does not support queries with: - aggregation (GROUP BY clause or aggregation functions
- * like min/max) - in memory aggregation (window function) - LIMIT/OFFSET clause(s) - without FROM
- * clause - JOIN - a subquery V2 also requires that the table being queried should be an OpenSearch
- * index. See PaginatedPlanCache.canConvertToCursor for usage.
+ * returns <em>true</em>, <em>PaginatedPlanCache.convertToCursor</em> will succeed.<br>
+ * Otherwise, it will fail.<br>
+ * The purpose of this visitor is to activate legacy engine fallback mechanism.<br>
+ * Currently, V2 engine does not support queries with:<br>
+ *
+ * <ul>
+ *   <li>aggregation (GROUP BY clause or aggregation functions like min/max)
+ *   <li>in memory aggregation (window function)
+ *   <li>LIMIT/OFFSET clause(s)
+ *   <li>without FROM clause
+ *   <li>JOIN
+ *   <li>a subquery
+ * </ul>
+ *
+ * V2 also requires that the table being queried should be an OpenSearch index.<br>
+ * See PaginatedPlanCache.canConvertToCursor for usage.
  */
 public class CanPaginateVisitor extends AbstractNodeVisitor<Boolean, Object> {
 

core/src/main/java/org/opensearch/sql/expression/ExpressionNodeVisitor.java

@@ -83,8 +83,12 @@ public T visitNamedAggregator(NamedAggregator node, C context) {
 
   /**
    * Call visitFunction() by default rather than visitChildren(). This makes CASE/WHEN able to be
-   * handled: 1) by visitFunction() if not overwritten: ex. FilterQueryBuilder 2) by
-   * visitCase/When() otherwise if any special logic: ex. ExprReferenceOptimizer
+   * handled:
+   *
+   * <ol>
+   *   <li>by visitFunction() if not overwritten: ex. FilterQueryBuilder
+   *   <li>by visitCase/When() otherwise if any special logic: ex. ExprReferenceOptimizer
+   * </ol>
    */
   public T visitCase(CaseClause node, C context) {
     return visitFunction(node, context);

core/src/main/java/org/opensearch/sql/expression/NamedExpression.java

@@ -15,8 +15,9 @@
 import org.opensearch.sql.expression.env.Environment;
 
 /**
- * Named expression that represents expression with name. Please see more details in associated
- * unresolved expression operator {@link org.opensearch.sql.ast.expression.Alias}.
+ * Named expression that represents expression with name.<br>
+ * Please see more details in associated unresolved expression operator<br>
+ * {@link org.opensearch.sql.ast.expression.Alias}.
  */
 @AllArgsConstructor
 @EqualsAndHashCode

core/src/main/java/org/opensearch/sql/expression/ReferenceExpression.java

@@ -61,21 +61,39 @@ public String toString() {
   }
 
   /**
-   * Resolve the ExprValue from {@link ExprTupleValue} using paths. Considering the following sample
-   * data. { "name": "bob smith" "project.year": 1990, "project": { "year": "2020" } "address": {
-   * "state": "WA", "city": "seattle", "project.year": 1990 } "address.local": { "state": "WA", } }
-   * The paths could be 1. top level, e.g. "name", which will be resolved as "bob smith" 2. multiple
-   * paths, e.g. "name.address.state", which will be resolved as "WA" 3. special case, the "." is
-   * the path separator, but it is possible that the path include ".", for handling this use case,
-   * we define the resolve rule as bellow, e.g. "project.year" is resolved as 1990 instead of 2020.
-   * Note. This logic only applied top level none object field. e.g. "address.local.state" been
-   * resolved to Missing. but "address.project.year" could been resolved as 1990.
+   * <pre>
+   * Resolve the ExprValue from {@link ExprTupleValue} using paths.
+   * Considering the following sample data.
+   * {
+   *   "name": "bob smith"
+   *   "project.year": 1990,
+   *   "project": {
+   *     "year": "2020"
+   *   }
+   *   "address": {
+   *     "state": "WA",
+   *     "city": "seattle",
+   *     "project.year": 1990
+   *   }
+   *   "address.local": {
+   *     "state": "WA",
+   *   }
+   * }
+   * The paths could be
+   * 1. top level, e.g. "name", which will be resolved as "bob smith"
+   * 2. multiple paths, e.g. "name.address.state", which will be resolved as "WA"
+   * 3. special case, the "." is the path separator, but it is possible that the path include
+   * ".", for handling this use case, we define the resolve rule as bellow, e.g. "project.year" is
+   * resolved as 1990 instead of 2020. Note. This logic only applied top level none object field.
+   * e.g. "address.local.state" been resolved to Missing. but "address.project.year" could been
+   * resolved as 1990.
    *
    * <p>Resolve Rule 1. Resolve the full name by combine the paths("x"."y"."z") as whole ("x.y.z").
    * 2. Resolve the path recursively through ExprValue.
    *
    * @param value {@link ExprTupleValue}.
    * @return {@link ExprTupleValue}.
+   * </pre>
    */
   public ExprValue resolve(ExprTupleValue value) {
     return resolve(value, paths);

core/src/main/java/org/opensearch/sql/expression/aggregation/AggregatorFunction.java

@@ -34,9 +34,11 @@
 import org.opensearch.sql.expression.function.FunctionSignature;
 
 /**
- * The definition of aggregator function avg, Accepts two numbers and produces a number. sum,
- * Accepts two numbers and produces a number. max, Accepts two numbers and produces a number. min,
- * Accepts two numbers and produces a number. count, Accepts two numbers and produces a number.
+ * The definition of aggregator functions <em>avg</em>, <em>sum</em>, <em>min</em>, <em>max</em> and
+ * <em>count</em>.<br>
+ * All of them accept a list of numbers and produce a number. <em>avg</em>, <em>min</em> and
+ * <em>max</em> also accept datetime types.<br>
+ * <em>count</em> accepts values of all types.
  */
 @UtilityClass
 public class AggregatorFunction {

core/src/main/java/org/opensearch/sql/expression/aggregation/NamedAggregator.java

@@ -12,7 +12,8 @@
 
 /**
  * NamedAggregator expression that represents expression with name. Please see more details in
- * associated unresolved expression operator {@link org.opensearch.sql.ast.expression.Alias}.
+ * associated unresolved expression operator<br>
+ * {@link org.opensearch.sql.ast.expression.Alias}.
  */
 @EqualsAndHashCode(callSuper = false)
 public class NamedAggregator extends Aggregator<AggregationState> {