Implemented a LocalDate-to-Date converter
authorKai Moritz <kai@juplo.de>
Mon, 21 Dec 2015 21:50:33 +0000 (22:50 +0100)
committerKai Moritz <kai@juplo.de>
Tue, 15 Aug 2017 17:44:37 +0000 (19:44 +0200)
src/main/java/de/juplo/jpa/converters/LocalDateConverter.java [new file with mode: 0644]

diff --git a/src/main/java/de/juplo/jpa/converters/LocalDateConverter.java b/src/main/java/de/juplo/jpa/converters/LocalDateConverter.java
new file mode 100644 (file)
index 0000000..d6a5c51
--- /dev/null
@@ -0,0 +1,39 @@
+package de.juplo.jpa.converters;
+
+import java.time.Instant;
+import java.time.LocalDate;
+import java.time.LocalDateTime;
+import java.time.LocalTime;
+import java.time.ZoneOffset;
+import java.util.Date;
+import javax.persistence.AttributeConverter;
+import javax.persistence.Converter;
+
+
+/**
+ * Converts a {@link LocalDate} to a {@link Date}, by converting it into
+ * an {@Instant} for the GMT-timezone at {@link LocalTime.MIDNIGHT} and then
+ * convering that {@link Instant} into a {@link Date} as suggested in the
+ * official Java 8 Time tutorial.
+ * <p>
+ * The {@link Date} can then be persisted as
+ * {@link java.persistene.TemporalType.DATE} with the help of the
+ * {@link java.persist.Tmporal}-annotation.
+ * @see https://docs.oracle.com/javase/tutorial/datetime/iso/legacy.html
+ * @author Kai Moritz
+ */
+@Converter(autoApply = true)
+public class LocalDateConverter implements AttributeConverter<LocalDate, Date>
+{
+  @Override
+  public Date convertToDatabaseColumn(LocalDate ld)
+  {
+    return Date.from(LocalDateTime.of(ld, LocalTime.MIDNIGHT).toInstant(ZoneOffset.UTC));
+  }
+
+  @Override
+  public LocalDate convertToEntityAttribute(Date date)
+  {
+    return LocalDate.from(date.toInstant());
+  }
+}