Key concepts:

• Preferences should not be tied to concrete implementation, they should be an interface that you can easily mock in your tests
• You should be able to provide implementation gateway in your platform layer
• Get your values through RxJava's Observable
• Get rid of always specifying a string key when you get or set preference, this should be strongly typed so that your IDE can help with autocompletion and your key<->value pair is always in sync
• Leverage annotation processing to automatically generate the wiring code between your preferences and platform gateway

@Preferences(name = "temp")
public interface SomePreferences {
    @Default(name = "name") String DEFAULT_VALUE = "DEFAULT_VALUE";
    @Get(name = "name") Observable<String> getValueName();
    @Set(name = "name") void setValue(String newValue);
    ...
    @Contains Observable<Boolean> contains(String key);
    @Delete void remove(String key);
}

Natively supported types are Boolean, Float, Integer, Long and String.

For everything else you have to extend IPreferenceAdapter and implement storing your entity via supported types. You can look at example of generic EnumAdapter. To include your adapter into processing just annotate it with @Adapter.

Each adapter should have a no-args constructor

For each parameter you have to always supply a default value as a field in an interface annotated with @Default. Type of parameter should be the same as in getter and setter.

Temp_Preferences preferences = new Temp_Preferences(new SharedPreferencesGatewayBuilder(contextRef));

Probably you'd store this in your dependency graph and inject it by interface For additional info look at the sample

Gradle:

repositories {
    ...
    mavenCentral()
    ...
}
...
dependencies {
    ...
    apt "com.malinskiy.sheldon2:compiler:$version"
    compile "com.malinskiy.sheldon2:core:$version"
    compile "com.malinskiy.sheldon2:gateway-sharedpreferences:$version"
    ...
}

Copyright 2017 Anton Malinskiy

Licensed under the Apache License, Version 2.0 (the "License");
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