Minor clean up of datetime and other classes (#198)

core/src/main/java/org/opensearch/sql/ast/statement/Explain.java

@@ -9,12 +9,14 @@
 package org.opensearch.sql.ast.statement;
 
 import lombok.Data;
+import lombok.EqualsAndHashCode;
 import org.opensearch.sql.ast.AbstractNodeVisitor;
 
 /**
  * Explain Statement.
  */
 @Data
+@EqualsAndHashCode(callSuper = false)
 public class Explain extends Statement {
 
   private final Statement statement;

core/src/main/java/org/opensearch/sql/ast/tree/Limit.java

@@ -17,7 +17,7 @@
 @RequiredArgsConstructor
 @Getter
 @ToString
-@EqualsAndHashCode
+@EqualsAndHashCode(callSuper = false)
 public class Limit extends UnresolvedPlan {
   private UnresolvedPlan child;
   private final Integer limit;

core/src/main/java/org/opensearch/sql/data/model/ExprDateValue.java

@@ -7,6 +7,7 @@
 package org.opensearch.sql.data.model;
 
 import static org.opensearch.sql.utils.DateTimeFormatters.DATE_TIME_FORMATTER_VARIABLE_NANOS_OPTIONAL;
+import static org.opensearch.sql.utils.DateTimeUtils.UTC_ZONE_ID;
 
 import com.google.common.base.Objects;
 import java.time.Instant;
@@ -68,7 +69,7 @@ public LocalDateTime datetimeValue() {
 
   @Override
   public Instant timestampValue() {
-    return ZonedDateTime.of(date, timeValue(), ExprTimestampValue.ZONE).toInstant();
+    return ZonedDateTime.of(date, timeValue(), UTC_ZONE_ID).toInstant();
   }
 
   @Override

core/src/main/java/org/opensearch/sql/data/model/ExprDatetimeValue.java

@@ -6,47 +6,34 @@
 
 package org.opensearch.sql.data.model;
 
+import static org.opensearch.sql.utils.DateTimeFormatters.DATE_TIME_FORMATTER_WITH_TZ;
+import static org.opensearch.sql.utils.DateTimeUtils.UTC_ZONE_ID;
+
 import com.google.common.base.Objects;
 import java.time.Instant;
 import java.time.LocalDate;
 import java.time.LocalDateTime;
 import java.time.LocalTime;
 import java.time.ZonedDateTime;
 import java.time.format.DateTimeFormatter;
-import java.time.format.DateTimeFormatterBuilder;
 import java.time.format.DateTimeParseException;
-import java.time.temporal.ChronoField;
 import java.time.temporal.ChronoUnit;
 import lombok.RequiredArgsConstructor;
 import org.opensearch.sql.data.type.ExprCoreType;
 import org.opensearch.sql.data.type.ExprType;
 import org.opensearch.sql.exception.SemanticCheckException;
 
+
 @RequiredArgsConstructor
 public class ExprDatetimeValue extends AbstractExprValue {
   private final LocalDateTime datetime;
 
-  private static final DateTimeFormatter FORMATTER_VARIABLE_NANOS;
-  private static final int MIN_FRACTION_SECONDS = 0;
-  private static final int MAX_FRACTION_SECONDS = 9;
-
-  static {
-    FORMATTER_VARIABLE_NANOS = new DateTimeFormatterBuilder()
-        .appendPattern("uuuu-MM-dd HH:mm:ss[xxx]")
-        .appendFraction(
-            ChronoField.NANO_OF_SECOND,
-            MIN_FRACTION_SECONDS,
-            MAX_FRACTION_SECONDS,
-            true)
-        .toFormatter();
-  }
-
   /**
    * Constructor with datetime string as input.
    */
   public ExprDatetimeValue(String datetime) {
     try {
-      this.datetime = LocalDateTime.parse(datetime, FORMATTER_VARIABLE_NANOS);
+      this.datetime = LocalDateTime.parse(datetime, DATE_TIME_FORMATTER_WITH_TZ);
     } catch (DateTimeParseException e) {
       throw new SemanticCheckException(String.format("datetime:%s in unsupported format, please "
           + "use yyyy-MM-dd HH:mm:ss[.SSSSSSSSS]", datetime));
@@ -70,7 +57,7 @@ public LocalTime timeValue() {
 
   @Override
   public Instant timestampValue() {
-    return ZonedDateTime.of(datetime, ExprTimestampValue.ZONE).toInstant();
+    return ZonedDateTime.of(datetime, UTC_ZONE_ID).toInstant();
   }
 
   @Override

core/src/main/java/org/opensearch/sql/data/model/ExprTimeValue.java

@@ -8,6 +8,7 @@
 
 import static java.time.format.DateTimeFormatter.ISO_LOCAL_TIME;
 import static org.opensearch.sql.utils.DateTimeFormatters.DATE_TIME_FORMATTER_VARIABLE_NANOS_OPTIONAL;
+import static org.opensearch.sql.utils.DateTimeUtils.UTC_ZONE_ID;
 
 import java.time.Instant;
 import java.time.LocalDate;
@@ -66,7 +67,7 @@ public LocalDateTime datetimeValue(FunctionProperties functionProperties) {
   }
 
   public Instant timestampValue(FunctionProperties functionProperties) {
-    return ZonedDateTime.of(dateValue(functionProperties), timeValue(), ExprTimestampValue.ZONE)
+    return ZonedDateTime.of(dateValue(functionProperties), timeValue(), UTC_ZONE_ID)
         .toInstant();
   }
 

core/src/main/java/org/opensearch/sql/data/model/ExprTimestampValue.java

@@ -8,12 +8,12 @@
 
 import static org.opensearch.sql.utils.DateTimeFormatters.DATE_TIME_FORMATTER_VARIABLE_NANOS;
 import static org.opensearch.sql.utils.DateTimeFormatters.DATE_TIME_FORMATTER_WITHOUT_NANO;
+import static org.opensearch.sql.utils.DateTimeUtils.UTC_ZONE_ID;
 
 import java.time.Instant;
 import java.time.LocalDate;
 import java.time.LocalDateTime;
 import java.time.LocalTime;
-import java.time.ZoneId;
 import java.time.format.DateTimeParseException;
 import java.time.temporal.ChronoUnit;
 import java.util.Objects;
@@ -27,10 +27,6 @@
  */
 @RequiredArgsConstructor
 public class ExprTimestampValue extends AbstractExprValue {
-  /**
-   * todo. only support UTC now.
-   */
-  public static final ZoneId ZONE = ZoneId.of("UTC");
 
   private final Instant timestamp;
 
@@ -40,7 +36,7 @@ public class ExprTimestampValue extends AbstractExprValue {
   public ExprTimestampValue(String timestamp) {
     try {
       this.timestamp = LocalDateTime.parse(timestamp, DATE_TIME_FORMATTER_VARIABLE_NANOS)
-          .atZone(ZONE)
+          .atZone(UTC_ZONE_ID)
           .toInstant();
     } catch (DateTimeParseException e) {
       throw new SemanticCheckException(String.format("timestamp:%s in unsupported format, please "
@@ -51,9 +47,9 @@ public ExprTimestampValue(String timestamp) {
 
   @Override
   public String value() {
-    return timestamp.getNano() == 0 ? DATE_TIME_FORMATTER_WITHOUT_NANO.withZone(ZONE)
+    return timestamp.getNano() == 0 ? DATE_TIME_FORMATTER_WITHOUT_NANO.withZone(UTC_ZONE_ID)
         .format(timestamp.truncatedTo(ChronoUnit.SECONDS))
-        : DATE_TIME_FORMATTER_VARIABLE_NANOS.withZone(ZONE).format(timestamp);
+        : DATE_TIME_FORMATTER_VARIABLE_NANOS.withZone(UTC_ZONE_ID).format(timestamp);
   }
 
   @Override
@@ -68,17 +64,17 @@ public Instant timestampValue() {
 
   @Override
   public LocalDate dateValue() {
-    return timestamp.atZone(ZONE).toLocalDate();
+    return timestamp.atZone(UTC_ZONE_ID).toLocalDate();
   }
 
   @Override
   public LocalTime timeValue() {
-    return timestamp.atZone(ZONE).toLocalTime();
+    return timestamp.atZone(UTC_ZONE_ID).toLocalTime();
   }
 
   @Override
   public LocalDateTime datetimeValue() {
-    return timestamp.atZone(ZONE).toLocalDateTime();
+    return timestamp.atZone(UTC_ZONE_ID).toLocalDateTime();
   }
 
   @Override
@@ -93,12 +89,12 @@ public String toString() {
 
   @Override
   public int compare(ExprValue other) {
-    return timestamp.compareTo(other.timestampValue().atZone(ZONE).toInstant());
+    return timestamp.compareTo(other.timestampValue().atZone(UTC_ZONE_ID).toInstant());
   }
 
   @Override
   public boolean equal(ExprValue other) {
-    return timestamp.equals(other.timestampValue().atZone(ZONE).toInstant());
+    return timestamp.equals(other.timestampValue().atZone(UTC_ZONE_ID).toInstant());
   }
 
   @Override

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

@@ -501,7 +501,6 @@ public static FunctionExpression to_seconds(Expression... expressions) {
     return to_seconds(FunctionProperties.None, expressions);
   }
 
-
   public static FunctionExpression week(
       FunctionProperties functionProperties, Expression... expressions) {
     return compile(functionProperties, BuiltinFunctionName.WEEK, expressions);

core/src/main/java/org/opensearch/sql/expression/datetime/DateTimeFunction.java

@@ -43,6 +43,7 @@
 import static org.opensearch.sql.utils.DateTimeFormatters.SHORT_DATE_LENGTH;
 import static org.opensearch.sql.utils.DateTimeFormatters.SINGLE_DIGIT_MONTH_DATE_LENGTH;
 import static org.opensearch.sql.utils.DateTimeFormatters.SINGLE_DIGIT_YEAR_DATE_LENGTH;
+import static org.opensearch.sql.utils.DateTimeUtils.UTC_ZONE_ID;
 import static org.opensearch.sql.utils.DateTimeUtils.extractDate;
 import static org.opensearch.sql.utils.DateTimeUtils.extractDateTime;
 
@@ -67,14 +68,12 @@
 import java.time.format.TextStyle;
 import java.time.temporal.ChronoUnit;
 import java.time.temporal.TemporalAmount;
-import java.util.Arrays;
 import java.util.Locale;
 import java.util.Map;
 import java.util.TimeZone;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Stream;
 import lombok.experimental.UtilityClass;
-import org.apache.commons.lang3.StringUtils;
 import org.apache.commons.lang3.tuple.Pair;
 import org.opensearch.sql.data.model.ExprDateValue;
 import org.opensearch.sql.data.model.ExprDatetimeValue;
@@ -84,11 +83,9 @@
 import org.opensearch.sql.data.model.ExprNullValue;
 import org.opensearch.sql.data.model.ExprStringValue;
 import org.opensearch.sql.data.model.ExprTimeValue;
-import org.opensearch.sql.data.model.ExprTimestampValue;
 import org.opensearch.sql.data.model.ExprValue;
 import org.opensearch.sql.data.type.ExprCoreType;
 import org.opensearch.sql.exception.ExpressionEvaluationException;
-import org.opensearch.sql.exception.SemanticCheckException;
 import org.opensearch.sql.expression.function.BuiltinFunctionName;
 import org.opensearch.sql.expression.function.BuiltinFunctionRepository;
 import org.opensearch.sql.expression.function.DefaultFunctionResolver;
@@ -191,6 +188,7 @@ public void register(BuiltinFunctionRepository repository) {
     repository.register(datediff());
     repository.register(datetime());
     repository.register(date_add());
+    repository.register(date_format());
     repository.register(date_sub());
     repository.register(day());
     repository.register(dayName());
@@ -236,13 +234,12 @@ public void register(BuiltinFunctionRepository repository) {
     repository.register(timestamp());
     repository.register(timestampadd());
     repository.register(timestampdiff());
-    repository.register(utc_date());
-    repository.register(utc_time());
-    repository.register(utc_timestamp());
-    repository.register(date_format());
     repository.register(to_days());
     repository.register(to_seconds());
     repository.register(unix_timestamp());
+    repository.register(utc_date());
+    repository.register(utc_time());
+    repository.register(utc_timestamp());
     repository.register(week(BuiltinFunctionName.WEEK));
     repository.register(week(BuiltinFunctionName.WEEKOFYEAR));
     repository.register(week(BuiltinFunctionName.WEEK_OF_YEAR));
@@ -1286,7 +1283,6 @@ private ExprValue exprConvertTZ(ExprValue startingDateTime, ExprValue fromTz, Ex
       return new ExprDatetimeValue(
           zonedDateTime.withZoneSameInstant(convertedToTz).toLocalDateTime());
 
-
       // Catches exception for invalid timezones.
       // ex. "+0:00" is an invalid timezone and would result in this exception being thrown.
     } catch (ExpressionEvaluationException | DateTimeException e) {
@@ -1334,7 +1330,6 @@ private ExprValue exprDateDiff(FunctionProperties functionProperties,
   private ExprValue exprDateTime(ExprValue dateTime, ExprValue timeZone) {
     String defaultTimeZone = TimeZone.getDefault().getID();
 
-
     try {
       LocalDateTime ldtFormatted =
           LocalDateTime.parse(dateTime.stringValue(), DATE_TIME_FORMATTER_STRICT_WITH_TZ);
@@ -1490,7 +1485,7 @@ private ExprValue exprFromUnixTime(ExprValue time) {
   private LocalDateTime exprFromUnixTimeImpl(ExprValue time) {
     return LocalDateTime.ofInstant(
             Instant.ofEpochSecond((long)Math.floor(time.doubleValue())),
-            ZoneId.of("UTC"))
+            UTC_ZONE_ID)
         .withNano((int)((time.doubleValue() % 1) * 1E9));
   }
 
@@ -1994,7 +1989,7 @@ private ExprValue exprUtcTime(FunctionProperties functionProperties) {
    */
   private ExprValue exprUtcTimeStamp(FunctionProperties functionProperties) {
     var zdt = ZonedDateTime.now(functionProperties.getQueryStartClock())
-        .withZoneSameInstant(ZoneId.of("UTC"));
+        .withZoneSameInstant(UTC_ZONE_ID);
     return new ExprDatetimeValue(zdt.toLocalDateTime());
   }