toml4j/README.md

toml4j

toml4j is a TOML 0.3.1 parser for Java.

For the bleeding-edge version integrating the latest specs, see the work-in-progress branch.

Installation

Add the following dependency to your POM (or equivalent for other dependency managers):

<dependency>
  <groupId>com.moandjiezana.toml</groupId>
  <artifactId>toml4j</artifactId>
  <version>0.3.1</version>
</dependency>

Requires Java 1.6.

Quick start

Toml toml = new Toml().parse(getTomlFile());
String someValue = toml.getString("someKey");
Date someDate = toml.getDate("someTable.someDate");
MyClass myClass = toml.to(MyClass.class);

Usage

A com.moandjiezana.toml.Toml instance is populated by calling one of parse(File), parse(InputStream), parse(Reader) or parse(String).

Toml toml = new Toml().parse("a=1");

An exception is thrown if the source is not valid TOML.

The data can then be accessed either by converting the Toml instance to your own class or by accessing tables and keys by name.

Custom classes

Toml#to(Class<T>) maps a Toml instance to the given class.

name = "Mwanji Ezana"

[address]
  street = "123 A Street"
  city = "AnyVille"
  
[contacts]
  "email address" = me@example.com

class Address {
  String street;
  String city;
}

class User {
  String name;
  Address address;
  Map<String, Object> contacts;
}

User user = new Toml().parse(tomlFile).to(User.class);

assert user.name.equals("Mwanji Ezana");
assert user.address.street.equals("123 A Street");
assert user.contacts.get("\"email address\"").equals("me@example.com");

Any keys not found in both the TOML and the class are ignored. Fields may be private.

Quoted keys cannot be mapped directly to a Java object, but they can be used as keys within a Map.

TOML primitives can be mapped to a number of Java types:

TOML	Java
Integer	int, long (or wrapper), java.math.BigInteger
Float	float, double (or wrapper), java.math.BigDecimal
String	String, enum, java.net.URI, java.net.URL
One-letter String	char, Character
Multiline and Literal Strings	String
Array	List, Set, array. The generic type can be anything that can be converted.
Table	Custom class, Map<String, Object>

Custom classes, Maps and collections thereof can be nested to any level. See TomlToClassTest#should_convert_fruit_table_array() for an example.

Key names

Use the getters to retrieve the data:

• getString(String)
• getDate(String)
• getBoolean(String)
• getLong(String)
• getDouble(String)
• getList(String)
• getTable(String) returns a new Toml instance containing only the keys in that table.
• getTables(String), for table arrays, returns List<Toml>.

You can also navigate values within a table with a compound key of the form table.key. Use a zero-based index such as tableArray[0].key to navigate table arrays.

Non-existent keys return null.

When retrieving quoted keys, the quotes must be used and the key must be spelled exactly the same way, including quotes and whitespace.

title = "TOML Example"
"sub title" = "Now with quoted keys"

[database]
  ports = [ 8001, 8001, 8002 ]
  enabled = true
  [database.credentials]
    password = "password"
    
[servers]
  cluster = "hyades"
  [servers.alpha]
  ip = "10.0.0.1"
  
[[networks]]
  name = "Level 1"
  [networks.status]
    bandwidth = 10

[[networks]]
  name = "Level 2"

[[networks]]
  name = "Level 3"
  [[networks.operators]]
    location = "Geneva"
  [[networks.operators]]
    location = "Paris"

Toml toml = new Toml().parse(getTomlFile());

String title = toml.getString("title");
String subTitle = toml.getString("\"sub title\"");
Boolean enabled = toml.getBoolean("database.enabled");
List<Long> ports = toml.getList("database.ports");
String password = toml.getString("database.credentials.password");

Toml servers = toml.getTable("servers");
String cluster = servers.getString("cluster"); // navigation is relative to current Toml instance
String ip = servers.getString("alpha.ip");

Toml network1 = toml.getTable("networks[0]");
String network2Name = toml.getString("networks[1].name"); // "Level 2"
List<Toml> network3Operators = toml.getTables("networks[2].operators");
String network3Operator2Location = toml.getString("networks[2].operators[1].location"); // "Paris"

Defaults

The constructor can be given a set of default values that will be used as fallbacks. For tables and table arrays, a shallow merge is performed.

# defaults
a = 2
b = 3

[table]
  c = 4
  d = 5

a = 1

[table]
  c = 2
  
[[array]]
  d = 3

Toml defaults = new Toml().parse(getDefaultsFile());
Toml toml = new Toml(defaults).parse(getTomlFile());

Long a = toml.getLong("a"); // returns 1, not 2
Long b = toml.getLong("b"); // returns 3
Long c = toml.getLong("c"); // returns null
Long tableC = toml.getLong("table.c"); // returns 2, not 4
Long tableD = toml.getLong("table.d"); // returns null, not 5
Long arrayD = toml.getLong("array[0].d"); // returns 3

Limitations

Date precision is limited to milliseconds.

License

toml4j is copyright of Moandji Ezana and is licensed under the MIT License