Android-TriOrm
a 3d database ORM experiment for Android. (used in two commercial projects). based around small tables concept and JVM Serialization
.
How to use
simply fork or download the project, you can also download and create .aar
file yourself.
Explanation
TriOrm
is a very light, simple and efficient ORM
with partial SQL
wrapping, with the following theme:
- every Object (
TriData
extension) is serialized and saved in the database. - you can only query by three fields:
id
,time_created
andtype
. - familiar no fuss Builder pattern to construct database.
- easy API to query, save and load typed objects.
- a very small usage of annotation(Optional).
- no learning curve whatsoever, no Boiler-plate code.
- Database is ready to use in less than couple of minutes.
- everything is typed.
- most of the presistent is carried by
JVM Serialization
and minimal small SQL table.
construct your Model/Tables
Simply extend TriData
with the following annotations(Optional).
@TriTable(dbName = "myDataBase", tableName = "user") public class User extends TriData {
public String firstName = "John";
public String lastName = "Dow";
public User() {
}
public User(String id) {
super(id);
}
}
@TriTable(dbName = "myDataBase", tableName = "location") public class Location extends TriData {
public String city
= "city";
public String state
= "state";
public Location() {
}
}
every TriData
has the following indexed/query-able properties with getters/setters:
setId(..)
- you can set the id or it will be set automatically for you.setType(..)
- some auxiliary field.setTimeCreated(..)
- also set-up for you by default.
construct your Database
constructing a database takes one line of code
new TriDatabase.Builder(this).addTable(User.class).addTable(Location.class).build();
and without annotations:
new TriDatabase.Builder(this).name("myDataBase").addTable("user", User.class).addTable("location", Location.class).build();
Saving into your Database
Simply invoke the save()
method on your extended TriData
object.
User user
= new User();
user.setId("theDude");
user.setType("Java programmer");
user.firstName = "Jimi"; user.lastName
= "Hendrix"; user.save();
loading a single object from your Database
Simply use the TriOrm.load(..)
Singleton and use your typed object.
User user = TriOrm.load(User.class, "theDude");
querying from your Database
Simply use the TriOrm.query(..)
builder Singleton and use your typed object.
ArrayList<User> list_users = TriOrm.query(User.class).timeCreatedFrom(0).timeCreatedTo(100).type("Java programmer").build().query();
you can query anything from the three properties: id
, timeCreated
and type
.
getting an instance of a table
Simply use the TriOrm.table(..)
Singleton and use your typed object. With table you can have more options and some sandbox methods.
TriTable<User> table = TriOrm.table(User.class);
Important Notes
The presistent layer is built around JVM Serialization
, therefore there are important considerations for when evolving your model/tables like any other database solution, beware of the folowing:
- TriData is based on
JVM Serialization
, therefore:- adding new fields is compatible.
- deleting/renaming exiting fields is not compatible, Therefore you will have to implement your
writeObject/readObject
and be smart about it. - adding new methods, altering previous methods is incompatible.
- look here for more info Durable Java: Serialization
- I recommend using primitive types as much as possible when designing the model/table.
- for best performence and compatibility control, you can experiment with
Externalizable
interface for reflection free. - contributions are most welcome with regards to compatiblity/performence.
Dependencies
- AOSP
Terms
- completely free source code. Apache License, Version 2.0.
- if you like it -> star or share it with others