Easy DB

A simple and easy database system developed for Android.

Installation

Using maven you can include the repository com.mauriciogiordano:easydb:0.1.0.

In gradle using maven compile "com.mauriciogiordano:easydb:0.1.0".

The JAR can be found here

Quick Usage

Currently this DB system uses the SharedPreferences mixed with json to store the data.

Up to this day it is only available simple collections with one-to-one and one-to-many relations.

You need to use the annotation @ModelField for every database field.

User.java

public class User extends HasManyModel<User, Note> {

    @ModelField
    private String id = "";
    @ModelField
    private String name = "";

    // required empty constructor!
    public User() {
        // current class, related class, cache opt
        super(User.class, Note.class, true);
    }

    // always use with context, otherwise you need to set it
    // manually with setContext method.
    public User(Context context) {
        // current class, related class, cache opt, context
        super(User.class, Note.class, true, context);
    }

    @Override
    public String getId() { return id;  }
    public void setId(String id) { this.id = id; }
    public String getName() { return name; }
    public void setName(String name) { this.name = name; }

    public static User fromJson(JSONObject json, Context context) {
        User dummy = new User(context);

        return dummy.fromJson(json);
    }

    public static User find(String id, Context context) {
        User dummy = new User(context);

        return dummy.find(id);
    }
}

Note.java

public class Note extends Model<Note> {

    @ModelField
    private String id = "";
    @ModelField
    private String title = "";
    @ModelField
    private String content = "";

    // required empty constructor!
    public Note() {
        // current class, cache opt
        super(Note.class, true);
    }

    // always use with context, otherwise you need to set it
    // manually with setContext method.
    public Note(Context context) {
        // current class, cache opt, context
        super(Note.class, true, context);
    }

    @Override
    public String getId() { return id;  }
    public void setId(String id) { this.id = id; }
    public String getTitle() { return title; }
    public void setTitle(String title) { this.title = title; }
    public String getContent() { return content; }
    public void setContent(String content) { this.content = content; }

    public static Note fromJson(JSONObject json, Context context) {
        Note dummy = new Note(context);

        return dummy.fromJson(json);
    }

    public static Note find(String id, Context context) {
        Note dummy = new Note(context);

        return dummy.find(id);
    }
}

Now you can test your application:

ExampleActivity.java

public class ExampleActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        User user = new User(this);

        user.setId("1");
        user.setName("Tom");

        Note a = new Note(this);

        a.setId("1");
        a.setTitle("First title");
        a.setContent("First content");

        Note b = new Note(this);

        b.setId("2");
        b.setTitle("Second title");
        b.setContent("Second content");

        user.save();
        a.save();
        b.save();

        user.addChild(a);
        user.addChild(b);

        user = null;

        user = User.find("1", this);

        if(user != null) {
            List<Note> children = user.findAllChildren();

            Log.d("User", user.toJson().toString());

            for(int i=0; i<children.size(); i++) {
                Log.d("Note " + i, children.get(i).toJson().toString());
            }
        }
    }
}

API

model.fromJson

Creates an object from a JSON representation. To access it statically, you need to create a dummy instance.

User user = User.fromJson(new JSONObject({ "id" : "1", "name" : "example" }));
user.setContext(context); // required if doing any operation like #save, #remove, etc.

model.toJson()

Returns a representation of the object in JSON format.

System.out.println(user.toJson()); // outputs: { "id" : "1", "name" : "example" }

model.find(String id)

Finds an object with id id. To access it statically, you need to create a dummy instance.

User user = User.find("1");
user.setContext(context); // required if doing any operation like #save, #remove, etc.

model.findAll()

Finds all object of that model. You need to create a dummy instance.

List<User> userList = User.findAll();

model.save()

Saves the object.

user.save();

model.remove()

Removes the object.

user.remove();

model.addOnUpdateListener(onUpdateListener)

Adds an onUpdateListener that will be triggered whenever the object is CREATED|UPDATED|REMOVED.

user.addOnUpdateListener(new OnUpdateListener {
    @Override
    public void onUpdate(Model model, Status status) {
        ...
    }
});

TODO

• Support id of any class that implements Comparable.
• Allow context as parameter for model.find, model.findAll, etc.

There are also available some listeners, such as OnUpdateListener

Built With

• java