Replace Collections.singletonList and emptyList with List.of in…

… cases where `List` is already imported. Signed-off-by: currantw <[email protected]>
opensearch-project · Dec 9, 2024 · c603113 · c603113
1 parent 823cffe
commit c603113
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Showing 24 changed files with 45 additions and 92 deletions.
diff --git a/core/src/main/java/org/opensearch/sql/ast/expression/AggregateFunction.java b/core/src/main/java/org/opensearch/sql/ast/expression/AggregateFunction.java
@@ -5,9 +5,6 @@
 
 package org.opensearch.sql.ast.expression;
 
-import static java.util.Collections.emptyList;
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -44,7 +41,7 @@ public class AggregateFunction extends UnresolvedExpression {
   public AggregateFunction(String funcName, UnresolvedExpression field) {
     this.funcName = funcName;
     this.field = field;
-    this.argList = emptyList();
+    this.argList = List.of();
   }
 
   /**
@@ -57,13 +54,13 @@ public AggregateFunction(String funcName, UnresolvedExpression field) {
   public AggregateFunction(String funcName, UnresolvedExpression field, Boolean distinct) {
     this.funcName = funcName;
     this.field = field;
-    this.argList = emptyList();
+    this.argList = List.of();
     this.distinct = distinct;
   }
 
   @Override
   public List<UnresolvedExpression> getChild() {
-    return singletonList(field);
+    return List.of(field);
   }
 
   @Override

diff --git a/core/src/main/java/org/opensearch/sql/ast/expression/Argument.java b/core/src/main/java/org/opensearch/sql/ast/expression/Argument.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.ast.expression;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -26,7 +24,7 @@ public class Argument extends UnresolvedExpression {
   //    private final DataType valueType;
   @Override
   public List<UnresolvedExpression> getChild() {
-    return singletonList(value);
+    return List.of(value);
   }
 
   @Override

diff --git a/core/src/main/java/org/opensearch/sql/ast/expression/In.java b/core/src/main/java/org/opensearch/sql/ast/expression/In.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.ast.expression;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -29,7 +27,7 @@ public class In extends UnresolvedExpression {
 
   @Override
   public List<UnresolvedExpression> getChild() {
-    return singletonList(field);
+    return List.of(field);
   }
 
   @Override

diff --git a/core/src/main/java/org/opensearch/sql/ast/expression/Interval.java b/core/src/main/java/org/opensearch/sql/ast/expression/Interval.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.ast.expression;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -30,7 +28,7 @@ public Interval(UnresolvedExpression value, String unit) {
 
   @Override
   public List<UnresolvedExpression> getChild() {
-    return singletonList(value);
+    return List.of(value);
   }
 
   @Override

diff --git a/core/src/main/java/org/opensearch/sql/ast/expression/Not.java b/core/src/main/java/org/opensearch/sql/ast/expression/Not.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.ast.expression;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -24,7 +22,7 @@ public class Not extends UnresolvedExpression {
 
   @Override
   public List<UnresolvedExpression> getChild() {
-    return singletonList(expression);
+    return List.of(expression);
   }
 
   @Override

diff --git a/core/src/main/java/org/opensearch/sql/ast/expression/UnresolvedArgument.java b/core/src/main/java/org/opensearch/sql/ast/expression/UnresolvedArgument.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.ast.expression;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -28,7 +26,7 @@ public UnresolvedArgument(String argName, UnresolvedExpression value) {
 
   @Override
   public List<UnresolvedExpression> getChild() {
-    return singletonList(value);
+    return List.of(value);
   }
 
   @Override

diff --git a/core/src/main/java/org/opensearch/sql/ast/tree/RareTopN.java b/core/src/main/java/org/opensearch/sql/ast/tree/RareTopN.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.ast.tree;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.AllArgsConstructor;
 import lombok.EqualsAndHashCode;
@@ -42,7 +40,7 @@ public RareTopN attach(UnresolvedPlan child) {
 
   @Override
   public List<UnresolvedPlan> getChild() {
-    return singletonList(this.child);
+    return List.of(this.child);
   }
 
   @Override

diff --git a/core/src/main/java/org/opensearch/sql/expression/text/TextFunctions.java b/core/src/main/java/org/opensearch/sql/expression/text/TextFunctions.java
@@ -5,7 +5,6 @@
 
 package org.opensearch.sql.expression.text;
 
-import static java.util.Collections.singletonList;
 import static org.opensearch.sql.data.type.ExprCoreType.ARRAY;
 import static org.opensearch.sql.data.type.ExprCoreType.INTEGER;
 import static org.opensearch.sql.data.type.ExprCoreType.STRING;
@@ -176,7 +175,7 @@ private DefaultFunctionResolver concat() {
         concatFuncName,
         funcName ->
             Pair.of(
-                new FunctionSignature(concatFuncName, singletonList(ARRAY)),
+                new FunctionSignature(concatFuncName, List.of(ARRAY)),
                 (funcProp, args) ->
                     new FunctionExpression(funcName, args) {
                       @Override

diff --git a/core/src/main/java/org/opensearch/sql/expression/window/ranking/RankingWindowFunction.java b/core/src/main/java/org/opensearch/sql/expression/window/ranking/RankingWindowFunction.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.expression.window.ranking;
 
-import static java.util.Collections.emptyList;
-
 import java.util.List;
 import java.util.stream.Collectors;
 import org.apache.commons.lang3.tuple.Pair;
@@ -35,7 +33,7 @@ public abstract class RankingWindowFunction extends FunctionExpression
   protected int rank;
 
   public RankingWindowFunction(FunctionName functionName) {
-    super(functionName, emptyList());
+    super(functionName, List.of());
   }
 
   @Override

diff --git a/core/src/main/java/org/opensearch/sql/planner/logical/LogicalAggregation.java b/core/src/main/java/org/opensearch/sql/planner/logical/LogicalAggregation.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.planner.logical;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -26,7 +24,7 @@ public class LogicalAggregation extends LogicalPlan {
   /** Constructor of LogicalAggregation. */
   public LogicalAggregation(
       LogicalPlan child, List<NamedAggregator> aggregatorList, List<NamedExpression> groupByList) {
-    super(singletonList(child));
+    super(List.of(child));
     this.aggregatorList = aggregatorList;
     this.groupByList = groupByList;
   }

diff --git a/core/src/main/java/org/opensearch/sql/planner/logical/LogicalDedupe.java b/core/src/main/java/org/opensearch/sql/planner/logical/LogicalDedupe.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.planner.logical;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -31,7 +29,7 @@ public LogicalDedupe(
       Integer allowedDuplication,
       Boolean keepEmpty,
       Boolean consecutive) {
-    super(singletonList(child));
+    super(List.of(child));
     this.dedupeList = dedupeList;
     this.allowedDuplication = allowedDuplication;
     this.keepEmpty = keepEmpty;

diff --git a/core/src/main/java/org/opensearch/sql/planner/logical/LogicalEval.java b/core/src/main/java/org/opensearch/sql/planner/logical/LogicalEval.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.planner.logical;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -28,7 +26,7 @@ public class LogicalEval extends LogicalPlan {
 
   /** Constructor of LogicalEval. */
   public LogicalEval(LogicalPlan child, List<Pair<ReferenceExpression, Expression>> expressions) {
-    super(singletonList(child));
+    super(List.of(child));
     this.expressions = expressions;
   }
 

diff --git a/core/src/main/java/org/opensearch/sql/planner/logical/LogicalNested.java b/core/src/main/java/org/opensearch/sql/planner/logical/LogicalNested.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.planner.logical;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import java.util.Map;
 import lombok.EqualsAndHashCode;
@@ -28,7 +26,7 @@ public LogicalNested(
       LogicalPlan childPlan,
       List<Map<String, ReferenceExpression>> fields,
       List<NamedExpression> projectList) {
-    super(singletonList(childPlan));
+    super(List.of(childPlan));
     this.fields = fields;
     this.projectList = projectList;
   }

diff --git a/core/src/main/java/org/opensearch/sql/planner/logical/LogicalProject.java b/core/src/main/java/org/opensearch/sql/planner/logical/LogicalProject.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.planner.logical;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -26,7 +24,7 @@ public LogicalProject(
       LogicalPlan child,
       List<NamedExpression> projectList,
       List<NamedExpression> namedParseExpressions) {
-    super(singletonList(child));
+    super(List.of(child));
     this.projectList = projectList;
     this.namedParseExpressions = namedParseExpressions;
   }

diff --git a/core/src/main/java/org/opensearch/sql/planner/logical/LogicalRareTopN.java b/core/src/main/java/org/opensearch/sql/planner/logical/LogicalRareTopN.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.planner.logical;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -32,7 +30,7 @@ public LogicalRareTopN(
       Integer noOfResults,
       List<Expression> fieldList,
       List<Expression> groupByList) {
-    super(singletonList(child));
+    super(List.of(child));
     this.commandType = commandType;
     this.noOfResults = noOfResults;
     this.fieldList = fieldList;

diff --git a/core/src/main/java/org/opensearch/sql/planner/logical/LogicalSort.java b/core/src/main/java/org/opensearch/sql/planner/logical/LogicalSort.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.planner.logical;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -25,7 +23,7 @@ public class LogicalSort extends LogicalPlan {
 
   /** Constructor of LogicalSort. */
   public LogicalSort(LogicalPlan child, List<Pair<SortOption, Expression>> sortList) {
-    super(singletonList(child));
+    super(List.of(child));
     this.sortList = sortList;
   }
 

diff --git a/core/src/main/java/org/opensearch/sql/planner/logical/LogicalWrite.java b/core/src/main/java/org/opensearch/sql/planner/logical/LogicalWrite.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.planner.logical;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -27,7 +25,7 @@ public class LogicalWrite extends LogicalPlan {
 
   /** Construct a logical write with given child node, table and column name list. */
   public LogicalWrite(LogicalPlan child, Table table, List<String> columns) {
-    super(singletonList(child));
+    super(List.of(child));
     this.table = table;
     this.columns = columns;
   }

diff --git a/core/src/main/java/org/opensearch/sql/planner/physical/FilterOperator.java b/core/src/main/java/org/opensearch/sql/planner/physical/FilterOperator.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.planner.physical;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -37,7 +35,7 @@ public <R, C> R accept(PhysicalPlanNodeVisitor<R, C> visitor, C context) {
 
   @Override
   public List<PhysicalPlan> getChild() {
-    return singletonList(input);
+    return List.of(input);
   }
 
   @Override

diff --git a/core/src/main/java/org/opensearch/sql/storage/write/TableWriteOperator.java b/core/src/main/java/org/opensearch/sql/storage/write/TableWriteOperator.java
@@ -5,8 +5,6 @@
 
 package org.opensearch.sql.storage.write;
 
-import static java.util.Collections.singletonList;
-
 import java.util.List;
 import lombok.RequiredArgsConstructor;
 import org.opensearch.sql.planner.physical.PhysicalPlan;
@@ -30,7 +28,7 @@ public <R, C> R accept(PhysicalPlanNodeVisitor<R, C> visitor, C context) {
 
   @Override
   public List<PhysicalPlan> getChild() {
-    return singletonList(input);
+    return List.of(input);
   }
 
   /**

diff --git a/core/src/test/java/org/opensearch/sql/analysis/SelectExpressionAnalyzerTest.java b/core/src/test/java/org/opensearch/sql/analysis/SelectExpressionAnalyzerTest.java
@@ -5,7 +5,6 @@
 
 package org.opensearch.sql.analysis;
 
-import static java.util.Collections.singletonList;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.doAnswer;
@@ -77,11 +76,11 @@ protected List<NamedExpression> analyze(UnresolvedExpression unresolvedExpressio
         .when(optimizer)
         .optimize(any(), any());
     return new SelectExpressionAnalyzer(expressionAnalyzer)
-        .analyze(singletonList(unresolvedExpression), analysisContext, optimizer);
+        .analyze(List.of(unresolvedExpression), analysisContext, optimizer);
   }
 
   protected void assertAnalyzeEqual(
       NamedExpression expected, UnresolvedExpression unresolvedExpression) {
-    assertEquals(singletonList(expected), analyze(unresolvedExpression));
+    assertEquals(List.of(expected), analyze(unresolvedExpression));
   }
 }