Properties To Settings

Generate at compile time settings classes (java 8) that can load java properties files or HOCON files.

Add the following dependency to your pom:

 <dependencies>
<dependency>
<groupId>org.backuity.p2s</groupId>
<artifactId>p2s</artifactId>
<version>2.5</version>
</dependency>
</dependencies>

Here is an example from the p2s tests:

importorg.p2s.Settings;
importjava.util.Optional;
@SettingspublicinterfaceSomeSettings {
Optional<Integer> timeout();
Stringname();
StringtheSurname();
}

You can then automatically load properties file :

 name = John Doe
timeout = 1234
the.surname = Toto

With the following code :

SomeSettingssettings = JulSettingsFactory.from("your-properties-from-classpath.properties")
.load(SomeSettings.class);
assertEquals("Toto", settings.theSurname());
assertEquals(Optional.of(1234), settings.timeout());

HOCON

The Human-Optimized Config Object Notation files are parsed using https://github.com/typesafehub/config.

To load configuration from an HOCON file add the following dependency to your pom:

 <dependencies>
<dependency>
<groupId>org.backuity.p2s</groupId>
<artifactId>p2s-hocon</artifactId>
<version>2.5</version>
</dependency>
</dependencies>

And use HoconSettingsFactory instead of JulSettingsFactory. So given the following HOCON file :

 name = "John Doe"
timeout = 1234
the.surname = "Toto"
# or alternatively:
# the { surname = "Toto" }

SomeSettingssettings = HoconSettingsFactory.from("your-hoconfrom-classpath.conf")
.load(SomeSettings.class);
assertEquals("Toto", settings.theSurname());
assertEquals(Optional.of(1234), settings.timeout());

This especially shines when used with nested types or arrays.

Basic Types

The following "basic" types are supported:

• Integer and int
• Long and long
• Boolean and boolean
• String

Lists

You can use parameters of type List:

@SettingspublicinterfaceListSettings {
List<String> languages();
List<Integer> sizes();
}

Using HOCON:

languages = ["fr", "en", "it"]
sizes = [12, 200, 3]

Or Properties (ids don't have to be sequential):

languages.1 = fr
languages.2 = en
languages.3 = it
sizes.1 = 12
sizes.20 = 200
sizes.300 = 3

Nested types

You can use nested settings interfaces :

@SettingspublicinterfaceParentSettings {
PersonSettingsmother();
PersonSettingsfather();
}
publicinterfacePersonSettings {
StringfirstName();
StringlastName();
Integerage();
AddressSettingsaddress();
}
publicinterfaceAddressSettings {
Stringcity();
Stringstreet();
}

You can load up a Parent with the following HOCON file :

mother {
first.name = "Mary Jane"
last.name = "Watson"
age = 32
address {
city = "Manhattan"
street = "1st avenue"
}
}
father {
first { name { "Cab" } }
last { name { "Calloway" } }
# ...
}

Or a properties:

mother.first.name = Alice
mother.last.name = Watt
mother.age = 31
mother.address.street = 3 rue de la paix
mother.address.city = Toulon
father.first.name = Bob
# ...

Nested types can also be used in lists:

@SettingspublicinterfaceListSettings {
List<AddressSettings> addresses();
}

With a HOCON file:

addresses = [{
city = "Marseille"
street = "Rue du bourg"
},{
city = "NYC"
street = "1st avenue"
}]

or with a Properties:

addresses.1.city = Marseille
addresses.1.street = Rue du bourg
addresses.2.city = NYC
addresses.2.street = 1st avenue

Nested types can be optional:

@SettingspublicinterfaceOptionalAddressSetting {
Optional<AddressSettings> address();
}

Fallback

From properties:

SomeSettingssettings = JulSettingsFactory.from("your-properties-from-classpath.properties")
.withFallback("a-fallback-from-classpath.properties")
.load(SomeSettings.class);

From code:

SomeSettingssettings = JulSettingsFactory.from("your-properties-from-classpath.properties")
.withFallback("the.surname", "Fantastic")
.withFallback("timeout", "123")
.load(SomeSettings.class);

Override settings

SomeSettingssettings = JulSettingsFactory.from("your-properties-from-classpath.properties")
.override("the.surname", "Fantastic")
.override("timeout", "789")
.load(SomeSettings.class);
assertEquals("Fantastic", settings.theSurname());
assertEquals(Optional.of(789), settings.timeout()); 

Release

See http://central.sonatype.org/pages/apache-maven.html.

cd p2s
# deploy a snapshot
mvn clean deploy
# perform a release - NOTE : you need to have a published gpg key installed on your system # update the version manually - commit push and tag
mvn clean deploy -P release
# promote to central (through the web interface)

Licence

The project is licenced under the Apache 2 licence.