com.typesafe.config
Interface ConfigValue

All Superinterfaces:

ConfigMergeable

All Known Subinterfaces:

ConfigList, ConfigObject

public interface ConfigValue
extends ConfigMergeable

An immutable value, following the JSON type schema.

Because this object is immutable, it is safe to use from multiple threads and there's no need for "defensive copies."

Do not implement ConfigValue; it should only be implemented by the config library. Arbitrary implementations will not work because the library internals assume a specific concrete implementation. Also, this interface is likely to grow new methods over time, so third-party implementations will break.

Method Summary

ConfigOrigin	origin() The origin of the value (file, line number, etc.), for debugging and error messages.
String	render() Renders the config value as a HOCON string.
String	render(ConfigRenderOptions options) Renders the config value to a string, using the provided options.
Object	unwrapped() Returns the value as a plain Java boxed value, that is, a String, Number, Boolean, Map<String,Object>, List<Object>, or null, matching the valueType() of this ConfigValue.
ConfigValueType	valueType() The ConfigValueType of the value; matches the JSON type schema.
ConfigValue	withFallback(ConfigMergeable other) Returns a new value computed by merging this value with another, with keys in this value "winning" over the other one.

Method Detail

origin

ConfigOrigin origin()

The origin of the value (file, line number, etc.), for debugging and error messages.

Returns:

where the value came from

valueType

ConfigValueType valueType()

The ConfigValueType of the value; matches the JSON type schema.

Returns:

value's type

unwrapped

Object unwrapped()

Returns the value as a plain Java boxed value, that is, a String, Number, Boolean, Map<String,Object>, List<Object>, or null, matching the valueType() of this ConfigValue. If the value is a ConfigObject or ConfigList, it is recursively unwrapped.

render

String render()

Renders the config value as a HOCON string. This method is primarily intended for debugging, so it tries to add helpful comments and whitespace.

If the config value has not been resolved (see Config.resolve()), it's possible that it can't be rendered as valid HOCON. In that case the rendering should still be useful for debugging but you might not be able to parse it.

This method is equivalent to render(ConfigRenderOptions.defaults()).

Returns:

the rendered value

render

String render(ConfigRenderOptions options)

Renders the config value to a string, using the provided options.

If the config value has not been resolved (see Config.resolve()), it's possible that it can't be rendered as valid HOCON. In that case the rendering should still be useful for debugging but you might not be able to parse it.

If the config value has been resolved and the options disable all HOCON-specific features (such as comments), the rendering will be valid JSON. If you enable HOCON-only features such as comments, the rendering will not be valid JSON.

Parameters:

options - the rendering options

Returns:

the rendered value

withFallback

ConfigValue withFallback(ConfigMergeable other)

Description copied from interface: ConfigMergeable

Returns a new value computed by merging this value with another, with keys in this value "winning" over the other one. Only ConfigObject and Config instances do anything in this method (they need to merge the fallback keys into themselves). All other values just return the original value, since they automatically override any fallback.

The semantics of merging are described in the spec for HOCON.

Note that objects do not merge "across" non-objects; if you write object.withFallback(nonObject).withFallback(otherObject), then otherObject will simply be ignored. This is an intentional part of how merging works. Both non-objects, and any object which has fallen back to a non-object, block subsequent fallbacks.

Specified by:

withFallback in interface ConfigMergeable

Parameters:

other - an object whose keys should be used if the keys are not present in this one

Returns:

a new object (or the original one, if the fallback doesn't get used)