feat: add getTimestampInstant() method to FieldValue (#2350)

* feat: add getReadableTimestampValue() method to FieldValue * 🦉 Updates from OwlBot post-processor See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md * 🦉 Updates from OwlBot post-processor See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md * chore: return java.time.Instant * 🦉 Updates from OwlBot post-processor See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md * 🦉 Updates from OwlBot post-processor See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md * chore: change method name * Update FieldValue.java * 🦉 Updates from OwlBot post-processor See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: Neenu1995

google-cloud-bigquery/src/main/java/com/google/cloud/bigquery/FieldValue.java

@@ -18,6 +18,7 @@
 
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkState;
+import static java.time.temporal.ChronoUnit.MICROS;
 
 import com.google.api.client.util.Data;
 import com.google.api.core.BetaApi;
@@ -26,6 +27,7 @@
 import java.io.Serializable;
 import java.math.BigDecimal;
 import java.math.RoundingMode;
+import java.time.Instant;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
@@ -36,6 +38,7 @@
  * query or when listing table data.
  */
 public class FieldValue implements Serializable {
+
  private static final int MICROSECONDS = 1000000;
  private static final long serialVersionUID = 469098630191710061L;
 
@@ -191,6 +194,21 @@ public long getTimestampValue() {
  return scaled.longValue();
  }
 
+ /**
+ * Returns this field's value as a {@code String}, representing a timestamp as an Instant. This
+ * method should only be used if the corresponding field has {@link LegacySQLTypeName#TIMESTAMP}
+ * type.
+ *
+ * @throws ClassCastException if the field is not a primitive type
+ * @throws NumberFormatException if the field's value could not be converted to {@link Long}
+ * @throws NullPointerException if {@link #isNull()} returns {@code true}
+ */
+ @SuppressWarnings("unchecked")
+ public Instant getTimestampInstant() {
+ checkNotNull(value);
+ return Instant.EPOCH.plus(getTimestampValue(), MICROS);
+ }
+
  /**
  * Returns this field's value as a {@link java.math.BigDecimal}. This method should only be used
  * if the corresponding field has {@link LegacySQLTypeName#NUMERIC} type.

google-cloud-bigquery/src/test/java/com/google/cloud/bigquery/it/ITBigQueryTest.java

@@ -2382,6 +2382,23 @@ public void testMultipleStatementsQueryException() throws InterruptedException {
  }
  }
 
+ @Test
+ public void testTimestamp() throws InterruptedException {
+ String query = "SELECT TIMESTAMP '2022-01-24T23:54:25.095574Z'";
+ String timestampStringValueExpected = "2022-01-24T23:54:25.095574Z";
+
+ TableResult resultInteractive =
+ bigquery.query(
+ QueryJobConfiguration.newBuilder(query)
+ .setDefaultDataset(DatasetId.of(DATASET))
+ .build());
+ for (FieldValueList row : resultInteractive.getValues()) {
+ FieldValue timeStampCell = row.get(0);
+ Instant timestampStringValueActual = timeStampCell.getTimestampInstant();
+ assertEquals(timestampStringValueExpected, timestampStringValueActual.toString());
+ }
+ }
+
  /* TODO(prasmish): replicate the entire test case for executeSelect */
  @Test
  public void testQuery() throws InterruptedException {