Merge branch '25-date-nano' into release-3.0.0-alpha2

Author: greenrobot-team

objectbox-java-api/src/main/java/io/objectbox/annotation/DatabaseType.java

@@ -0,0 +1,16 @@
+package io.objectbox.annotation;
+
+/**
+ * Use with {@link Type @Type} to specify how a property value is stored in the database.
+ * <p>
+ * This is e.g. useful for integer types that can mean different things depending on interpretation.
+ * For example a 64-bit long value might be interpreted as time in milliseconds, or as time in nanoseconds.
+ */
+public enum DatabaseType {
+
+    /**
+     * High precision time stored as a 64-bit long representing nanoseconds since 1970-01-01 (unix epoch).
+     */
+    DateNano
+
+}

objectbox-java-api/src/main/java/io/objectbox/annotation/Type.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2019 ObjectBox Ltd. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.objectbox.annotation;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Specifies the database type of an annotated property as one of {@link DatabaseType}.
+ */
+@Retention(RetentionPolicy.CLASS)
+@Target({ElementType.FIELD})
+public @interface Type {
+
+    DatabaseType value();
+
+}

objectbox-java/src/main/java/io/objectbox/model/PropertyFlags.java

@@ -82,5 +82,13 @@ private PropertyFlags() { }
    * Note: Don't combine with ID, they are always unsigned internally.
    */
   public static final int UNSIGNED = 8192;
+  /**
+   * By defining an ID companion property, the entity type uses a special ID encoding scheme involving this property
+   * in addition to the ID.
+   *
+   * For Time Series IDs, a companion property of type Date or DateNano represents the exact timestamp.
+   * (Future idea: string hash IDs, with a String companion property to store the full string ID).
+   */
+  public static final int ID_COMPANION = 16384;
 }
 

objectbox-java/src/main/java/io/objectbox/model/PropertyType.java

@@ -18,6 +18,9 @@
 
 package io.objectbox.model;
 
+/**
+ * Basic type of a property
+ */
 public final class PropertyType {
   private PropertyType() { }
   /**
@@ -34,14 +37,17 @@ private PropertyType() { }
   public static final short Double = 8;
   public static final short String = 9;
   /**
-   * Internally stored as a 64 bit long(?)
+   * Date/time stored as a 64 bit long representing milliseconds since 1970-01-01 (unix epoch)
    */
   public static final short Date = 10;
   /**
    * Relation to another entity
    */
   public static final short Relation = 11;
-  public static final short Reserved1 = 12;
+  /**
+   * High precision date/time stored as a 64 bit long representing nanoseconds since 1970-01-01 (unix epoch)
+   */
+  public static final short DateNano = 12;
   public static final short Reserved2 = 13;
   public static final short Reserved3 = 14;
   public static final short Reserved4 = 15;
@@ -61,8 +67,9 @@ private PropertyType() { }
   public static final short DoubleVector = 29;
   public static final short StringVector = 30;
   public static final short DateVector = 31;
+  public static final short DateNanoVector = 32;
 
-  public static final String[] names = { "Unknown", "Bool", "Byte", "Short", "Char", "Int", "Long", "Float", "Double", "String", "Date", "Relation", "Reserved1", "Reserved2", "Reserved3", "Reserved4", "Reserved5", "Reserved6", "Reserved7", "Reserved8", "Reserved9", "Reserved10", "BoolVector", "ByteVector", "ShortVector", "CharVector", "IntVector", "LongVector", "FloatVector", "DoubleVector", "StringVector", "DateVector", };
+  public static final String[] names = { "Unknown", "Bool", "Byte", "Short", "Char", "Int", "Long", "Float", "Double", "String", "Date", "Relation", "DateNano", "Reserved2", "Reserved3", "Reserved4", "Reserved5", "Reserved6", "Reserved7", "Reserved8", "Reserved9", "Reserved10", "BoolVector", "ByteVector", "ShortVector", "CharVector", "IntVector", "LongVector", "FloatVector", "DoubleVector", "StringVector", "DateVector", "DateNanoVector", };
 
   public static String name(int e) { return names[e]; }
 }