Typesafe Config 1.4.3 · com.typesafe.config.ConfigObject

Subtype of ConfigValue representing an object (AKA dictionary or map) value, as in JSON's curly brace { "a" : 42 } syntax.

An object may also be viewed as a Config by calling ConfigObject#toConfig().

ConfigObject implements java.util.Map<String, ConfigValue> so you can use it like a regular Java map. Or call unwrapped() to unwrap the map to a map with plain Java values rather than ConfigValue.

Like all ConfigValue subtypes, ConfigObject is immutable. This makes it threadsafe and you never have to create "defensive copies." The mutator methods from java.util.Map all throw java.lang.UnsupportedOperationException.

The ConfigValue#valueType method on an object returns ConfigValueType#OBJECT.

In most cases you want to use the Config interface rather than this one. Call toConfig() to convert a ConfigObject to a Config.

The API for a ConfigObject is in terms of keys, while the API for a Config is in terms of path expressions. Conceptually, ConfigObject is a tree of maps from keys to values, while a Config is a one-level map from paths to values.

Use ConfigUtil#joinPath and ConfigUtil#splitPath to convert between path expressions and individual path elements (keys).

A ConfigObject may contain null values, which will have ConfigValue#valueType() equal to ConfigValueType#NULL. If ConfigObject#get(Object) returns Java's null then the key was not present in the parsed file (or wherever this value tree came from). If get("key") returns a ConfigValue with type ConfigValueType#NULL then the key was set to null explicitly in the config file.

Do not implement interface ConfigObject; 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

Modifier and Type	Method and Description
public ConfigValue	Returns: the value at the key or null if none get(Object key to look up key) Redeclares java.util.Map.get. Gets a `ConfigValue` at the given key, or returns null if there is no value.
public Config	Returns: a `Config` with this object as its root toConfig() Converts this object to a `Config` instance, enabling you to use path expressions to find values in the object.
public Map<String, Object>	Returns: a `java.util.Map` containing plain Java objects unwrapped() Redeclares com.typesafe.config.ConfigValue.unwrapped. Recursively unwraps the object, returning a map from String to whatever plain Java values are unwrapped from the object's values.
public ConfigObject	withFallback(ConfigMergeable an object whose keys should be used as fallbacks, if the keys are not present in this one other) Redeclares com.typesafe.config.ConfigValue.withFallback. Returns a new value computed by merging this value with another, with keys in this value "winning" over the other one.
public ConfigObject	Returns: a copy of the object minus all keys except the one specified withOnlyKey(String key to keep key) Clone the object with only the given key (and its children) retained; all sibling keys are removed.
public ConfigObject	withOrigin(ConfigOrigin the origin set on the returned value origin) Redeclares com.typesafe.config.ConfigValue.withOrigin. Returns a `ConfigValue` based on this one, but with the given origin.
public ConfigObject	Returns: a copy of the object minus the specified key withoutKey(String key to remove key) Clone the object with the given key removed.
public ConfigObject	Returns: the new instance with the new map entry withValue(String key to add key, ConfigValue value at the new key value) Returns a `ConfigObject` based on this one, but with the given key set to the given value.

Method Detail

get back to summary

get	back to summary
public ConfigValue get(Object key) Redeclares java.util.Map.get. Gets a `ConfigValue` at the given key, or returns null if there is no value. The returned `ConfigValue` may have `ConfigValueType#NULL` or any other type, and the passed-in key must be a key in this object (rather than a path expression). Parameters key:Object key to look up Returns:ConfigValue the value at the key or null if none Annotations @Override

public ConfigValue get(Object key)

Redeclares java.util.Map.get.

Gets a ConfigValue at the given key, or returns null if there is no value. The returned ConfigValue may have ConfigValueType#NULL or any other type, and the passed-in key must be a key in this object (rather than a path expression).

Parameters

key:Object: key to look up

Returns:ConfigValue

the value at the key or null if none

Annotations

@Override

toConfig back to summary

toConfig	back to summary
public Config toConfig() Converts this object to a `Config` instance, enabling you to use path expressions to find values in the object. This is a constant-time operation (it is not proportional to the size of the object). Returns:Config a `Config` with this object as its root

public Config toConfig()

Converts this object to a Config instance, enabling you to use path expressions to find values in the object. This is a constant-time operation (it is not proportional to the size of the object).

Returns:Config: a Config with this object as its root

unwrapped back to summary

unwrapped	back to summary
public Map<String, Object> unwrapped() Redeclares com.typesafe.config.ConfigValue.unwrapped. Recursively unwraps the object, returning a map from String to whatever plain Java values are unwrapped from the object's values. Returns:Map<String, Object> a `java.util.Map` containing plain Java objects Annotations @Override

public Map<String, Object> unwrapped()

Redeclares com.typesafe.config.ConfigValue.unwrapped.

Recursively unwraps the object, returning a map from String to whatever plain Java values are unwrapped from the object's values.

Returns:Map<String, Object>

a java.util.Map containing plain Java objects

Annotations

@Override

withFallback back to summary

withFallback	back to summary
public ConfigObject withFallback(ConfigMergeable other) Redeclares com.typesafe.config.ConfigValue.withFallback. Doc from com.typesafe.config.ConfigMergeable.withFallback. Returns a new value computed by merging this value with another, with keys in this value "winning" over the other one. This associative operation may be used to combine configurations from multiple sources (such as multiple configuration files). The semantics of merging are described in the spec for HOCON. Merging typically occurs when either the same object is created twice in the same file, or two config files are both loaded. For example: foo = { a: 42 } foo = { b: 43 } Here, the two objects are merged as if you had written: foo = { a: 42, b: 43 } 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. This means 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, because non-objects such as strings and integers replace (rather than merging with) any prior value: foo = { a: 42 } foo = 10 Here, the number 10 "wins" and the value of `foo` would be simply 10. Again, for details see the spec. Parameters other:ConfigMergeable an object whose keys should be used as fallbacks, if the keys are not present in this one Returns:ConfigObject a new object (or the original one, if the fallback doesn't get used) Annotations @Override

public ConfigObject withFallback(ConfigMergeable other)

Redeclares com.typesafe.config.ConfigValue.withFallback.

Doc from com.typesafe.config.ConfigMergeable.withFallback.

Returns a new value computed by merging this value with another, with keys in this value "winning" over the other one.

This associative operation may be used to combine configurations from multiple sources (such as multiple configuration files).

The semantics of merging are described in the spec for HOCON. Merging typically occurs when either the same object is created twice in the same file, or two config files are both loaded. For example:

 foo = { a: 42 }
 foo = { b: 43 }

Here, the two objects are merged as if you had written:

 foo = { a: 42, b: 43 }

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. This means 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, because non-objects such as strings and integers replace (rather than merging with) any prior value:

foo = { a: 42 }
foo = 10

Here, the number 10 "wins" and the value of foo would be simply 10. Again, for details see the spec.

Parameters

other:ConfigMergeable: an object whose keys should be used as fallbacks, if the keys are not present in this one

Returns:ConfigObject

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

Annotations

@Override

withOnlyKey	back to summary
public ConfigObject withOnlyKey(String key) Clone the object with only the given key (and its children) retained; all sibling keys are removed. Parameters key:String key to keep Returns:ConfigObject a copy of the object minus all keys except the one specified

withOnlyKey

back to summary

public ConfigObject withOnlyKey(String key)

Clone the object with only the given key (and its children) retained; all sibling keys are removed.

Parameters

key:String: key to keep

Returns:ConfigObject

a copy of the object minus all keys except the one specified

withOrigin back to summary

withOrigin	back to summary
public ConfigObject withOrigin(ConfigOrigin origin) Redeclares com.typesafe.config.ConfigValue.withOrigin. Doc from com.typesafe.config.ConfigValue.withOrigin. Returns a `ConfigValue` based on this one, but with the given origin. This is useful when you are parsing a new format of file or setting comments for a single ConfigValue. Parameters origin:ConfigOrigin the origin set on the returned value Returns:ConfigObject the new ConfigValue with the given origin Annotations @Override

public ConfigObject withOrigin(ConfigOrigin origin)

Redeclares com.typesafe.config.ConfigValue.withOrigin.

Doc from com.typesafe.config.ConfigValue.withOrigin.

Returns a ConfigValue based on this one, but with the given origin. This is useful when you are parsing a new format of file or setting comments for a single ConfigValue.

Parameters

origin:ConfigOrigin: the origin set on the returned value

Returns:ConfigObject

the new ConfigValue with the given origin

Annotations

@Override

withoutKey	back to summary
public ConfigObject withoutKey(String key) Clone the object with the given key removed. Parameters key:String key to remove Returns:ConfigObject a copy of the object minus the specified key

withoutKey

back to summary

public ConfigObject withoutKey(String key)

Clone the object with the given key removed.

Parameters

key:String: key to remove

Returns:ConfigObject

a copy of the object minus the specified key

withValue back to summary

withValue	back to summary
public ConfigObject withValue(String key, ConfigValue value) Returns a `ConfigObject` based on this one, but with the given key set to the given value. Does not modify this instance (since it's immutable). If the key already has a value, that value is replaced. To remove a value, use `ConfigObject#withoutKey(String)`. Parameters key:String key to add value:ConfigValue value at the new key Returns:ConfigObject the new instance with the new map entry

public ConfigObject withValue(String key, ConfigValue value)

Returns a ConfigObject based on this one, but with the given key set to the given value. Does not modify this instance (since it's immutable). If the key already has a value, that value is replaced. To remove a value, use ConfigObject#withoutKey(String).

Parameters

key:String: key to add
value:ConfigValue: value at the new key

Returns:ConfigObject

the new instance with the new map entry

public Interface ConfigObject

Method Summary

Method Detail