ConfigFactory

Obtains the default application-specific configuration, which defaults to parsing application.conf, application.json, and application.properties on the classpath, but can also be rerouted using the config.file, config.resource, and config.url system properties.

The no-arguments load() method automatically stacks the defaultReference(), defaultApplication(), and defaultOverrides() configs. You would use defaultApplication() directly only if you're somehow customizing behavior by reimplementing load().

The configuration returned by defaultApplication() will not be resolved already, in contrast to defaultReference() and defaultOverrides(). This is because application.conf would normally be resolved ''after'' merging with the reference and override configs.

If the system properties config.resource, config.file, or config.url are set, then the classpath resource, file, or URL specified in those properties will be used rather than the default application.{conf,json,properties]] classpath resources. These system properties should not be set in code (after all, you can just parse whatever you want manually and then use load(Config) if you don't want to use application.conf). The properties are intended for use by the person or script launching the application. For example someone might have a production.conf that include application.conf but then change a couple of values. When launching the app they could specify -Dconfig.resource=production.conf to get production mode.

If no system properties are set to change the location of the default configuration, defaultApplication() is equivalent to ConfigFactory.parseResources("application").

Like defaultApplication() but allows you to specify a class loader to use rather than the current context class loader.

Like defaultApplication() but allows you to specify parse options.

Obtains the default override configuration, which currently consists of system properties. The returned override configuration will already have substitutions resolved.

The load() methods merge this configuration for you automatically.

Future versions may get overrides in more places. It is not guaranteed that this method only uses system properties.

Like defaultOverrides() but allows you to specify a class loader to use rather than the current context class loader.

Obtains the default reference configuration, which is currently created by merging all resources "reference.conf" found on the classpath and overriding the result with system properties. The returned reference configuration will already have substitutions resolved.

Libraries and frameworks should ship with a "reference.conf" in their jar.

The reference config must be looked up in the class loader that contains the libraries that you want to use with this config, so the "reference.conf" for each library can be found. Use defaultReference(ClassLoader) if the context class loader is not suitable.

The load() methods merge this configuration for you automatically.

Future versions may look for reference configuration in more places. It is not guaranteed that this method ''only'' looks at "reference.conf".

Like defaultReference() but allows you to specify a class loader to use rather than the current context class loader.

Gets an empty configuration. See also empty(String) to create an empty configuration with a description, which may improve user-visible error messages.

Gets an empty configuration with a description to be used to create a ConfigOrigin for this Config. The description should be very short and say what the configuration is, like "default settings" or "foo settings" or something. (Presumably you will merge some actual settings into this empty config using Config.withFallback, making the description more useful.)

Reloads any cached configs, picking up changes to system properties for example. Because a Config is immutable, anyone with a reference to the old configs will still have the same outdated objects. However, new calls to load() or defaultOverrides() or defaultReference() may return a new object.

This method is primarily intended for use in unit tests, for example, that may want to update a system property then confirm that it's used correctly. In many cases, use of this method may indicate there's a better way to set up your code.

Caches may be reloaded immediately or lazily; once you call this method, the reload can occur at any time, even during the invalidation process. So FIRST make the changes you'd like the caches to notice, then SECOND call this method to invalidate caches. Don't expect that invalidating, making changes, then calling load(), will work. Make changes before you invalidate.

Loads an application's configuration from the given classpath resource or classpath resource basename, sandwiches it between default reference config and default overrides, and then resolves it. The classpath resource is "raw" (it should have no "/" prefix, and is not made relative to any package, so it's like ClassLoader.getResource not Class.getResource).

Resources are loaded from the current thread's Thread.getContextClassLoader. In general, a library needs its configuration to come from the class loader used to load that library, so the proper "reference.conf" are present.

The loaded object will already be resolved (substitutions have already been processed). As a result, if you add more fallbacks then they won't be seen by substitutions. Substitutions are the ${foo.bar} syntax. If you want to parse additional files or something then you need to use load(Config).

To load a standalone resource (without the default reference and default overrides), use parseResourcesAnySyntax(String) rather than this method. To load only the reference config use defaultReference() and to load only the overrides use defaultOverrides().

Like ConfigFactory.load(String) but uses the supplied class loader instead of the current thread's context class loader.

To load a standalone resource (without the default reference and default overrides), use parseResourcesAnySyntax(ClassLoader,String) rather than this method. To load only the reference config use defaultReference(ClassLoader) and to load only the overrides use defaultOverrides(ClassLoader).

Like ConfigFactory.load(String) but allows you to specify parse and resolve options.

Like load(String,ConfigParseOptions,ConfigResolveOptions) but has a class loader parameter that overrides any from the ConfigParseOptions.

Assembles a standard configuration using a custom Config object rather than loading "application.conf". The Config object will be sandwiched between the default reference config and default overrides and then resolved.

Like load(Config) but allows you to specify the class loader for looking up resources.

Like load(Config) but allows you to specify ConfigResolveOptions.

Like load(Config,ConfigResolveOptions) but allows you to specify a class loader other than the context class loader.

Loads a default configuration, equivalent to load(Config) `ConfigFactory.load(defaultApplication()) in most cases. This configuration should be used by libraries and frameworks unless an application provides a different one.

This method may return a cached singleton so will not see changes to system properties or config files. (Use invalidateCaches() to force it to reload.)

Like load() but allows specifying parse options.

Like load() but allows specifying a class loader other than the thread's current context class loader.

Like load() but allows specifying a class loader other than the thread's current context class loader and also specify parse options.

Like load() but allows specifying a class loader other than the thread's current context class loader and also specify resolve options.

Like load() but allows specifying a class loader other than the thread's current context class loader, parse options, and resolve options.

Like load() but allows specifying parse options and resolve options.

Parses a file into a Config instance. Does not call Config.resolve() or merge the file with any other configuration; this method parses a single file and does nothing else. It does process "include" statements in the parsed file, and may end up doing other IO due to those statements.

Parses a file into a Config instance as with parseFile(File,ConfigParseOptions) but always uses the default parse options.

Parses a file with a flexible extension. If the fileBasename already ends in a known extension, this method parses it according to that extension (the file's syntax must match its extension). If the fileBasename does not end in an extension, it parses files with all known extensions and merges whatever is found.

In the current implementation, the extension ".conf" forces ConfigSyntax.CONF, ".json" forces ConfigSyntax.JSON, and ".properties" forces ConfigSyntax.PROPERTIES. When merging files, ".conf" falls back to ".json" falls back to ".properties".

Future versions of the implementation may add additional syntaxes or additional extensions. However, the ordering (fallback priority) of the three current extensions will remain the same.

If options forces a specific syntax, this method only parses files with an extension matching that syntax.

If ConfigParseOptions#getAllowMissing is true, then no files have to exist; if false, then at least one file has to exist.

Like parseFileAnySyntax(File,ConfigParseOptions) but always uses default parse options.

Creates a Config based on a java.util.Map from paths to plain Java values. Similar to ConfigValueFactory.fromMap(Map,String), except the keys in the map are path expressions, rather than keys; and correspondingly it returns a Config instead of a ConfigObject. This is more convenient if you are writing literal maps in code, and less convenient if you are getting your maps from some data source such as a parser.

An exception will be thrown (and it is a bug in the caller of the method) if a path is both an object and a value, for example if you had both "a=foo" and "a.b=bar", then "a" is both the string "foo" and the parent object of "b". The caller of this method should ensure that doesn't happen.

See the other overload of ConfigFactory.parseMap(Map,String) for details, this one just uses a default origin description.

Converts a Java java.util.Properties object to a ConfigObject using the rules documented in the HOCON spec The keys in the Properties object are split on the period character '.' and treated as paths. The values will all end up as string values. If you have both "a=foo" and "a.b=bar" in your properties file, so "a" is both the object containing "b" and the string "foo", then the string value is dropped.

If you want to have System.getProperties() as a ConfigObject, it's better to use the systemProperties method which returns a cached global singleton.

Like parseProperties(Properties, ConfigParseOptions) but uses default parse options.

Parses a Reader into a Config instance. Does not call Config.resolve() or merge the parsed stream with any other configuration; this method parses a single stream and does nothing else. It does process "include" statements in the parsed stream, and may end up doing other IO due to those statements.

Parses a reader into a Config instance as with parseReader(Reader, ConfigParseOptions) but always uses the default parse options.

Parses all resources on the classpath with the given name and merges them into a single Config.

If the resource name does not begin with a "/", it will have the supplied class's package added to it, in the same way as java.lang.Class.getResource.

Duplicate resources with the same name are merged such that ones returned earlier from ClassLoader.getResources fall back to (have higher priority than) the ones returned later# This implies that resources earlier in the classpath override those later in the classpath when they configure the same setting# However, in practice real applications may not be consistent about classpath ordering, so be careful# It may be best to avoid assuming too much#

Like parseResources(Class,String,ConfigParseOptions) but always uses default parse options.

Parses all resources on the classpath with the given name and merges them into a single Config.

This works like java.lang.ClassLoader.getResource, not like java.lang.Class.getResource, so the name never begins with a slash.

See parseResources(Class,String,ConfigParseOptions) for full details.

Like parseResources(ClassLoader,String,ConfigParseOptions) but always uses default parse options.

Like parseResources(ClassLoader,String,ConfigParseOptions) but uses thread's current context class loader if none is set in the ConfigParseOptions.

Like parseResources(ClassLoader,String) but uses thread's current context class loader.

Parses classpath resources with a flexible extension. In general, this method has the same behavior as parseFileAnySyntax(File,ConfigParseOptions) but for classpath resources instead, as in parseResources(String).

There is a thorny problem with this method, which is that java.lang.ClassLoader.getResources must be called separately for each possible extension. The implementation ends up with separate lists of resources called "basename.conf" and "basename.json" for example. As a result, the ideal ordering between two files with different extensions is unknown; there is no way to figure out how to merge the two lists in classpath order. To keep it simple, the lists are simply concatenated, with the same syntax priorities as parseFileAnySyntax(File,ConfigParseOptions)

• all ".conf" resources are ahead of all ".json" resources which are ahead of all ".properties" resources.

Like parseResourcesAnySyntax(Class,String,ConfigParseOptions) but always uses default parse options.

Parses classpath resources with a flexible extension. In general, this method has the same behavior as parseFileAnySyntax(File,ConfigParseOptions) but for classpath resources instead, as in parseResources(ClassLoader,String,ConfigParseOptions).

parseResourcesAnySyntax(Class,String,ConfigParseOptions) differs in the syntax for the resource name, but it is useful to review for some details and caveats on this method.

Like parseResourcesAnySyntax(ClassLoader,String,ConfigParseOptions) but always uses default parse options.

Like parseResourcesAnySyntax(ClassLoader,String,ConfigParseOptions) but uses thread's current context class loader.

Like parseResourcesAnySyntax(ClassLoader,String) but uses thread's current context class loader.

Parses a string (which should be valid HOCON or JSON by default, or the syntax specified in the options otherwise).

Parses a string (which should be valid HOCON or JSON).

Parses a URL into a Config instance. Does not call Config.resolve() or merge the parsed stream with any other configuration; this method parses a single stream and does nothing else. It does process "include" statements in the parsed stream, and may end up doing other IO due to those statements.

Parses a url into a Config instance as with ConfigFactory.parseURL(URL,ConfigParseOptions) but always uses the default parse options.

Gets a Config containing the system's environment variables. This method can return a global immutable singleton.

Environment variables are used as fallbacks when resolving substitutions whether or not this object is included in the config being resolved, so you probably don't need to use this method for most purposes. It can be a nicer API for accessing environment variables than raw java.lang.System.getenv(String) though, since you can use methods such as Config.getInt.

Gets a Config containing the system properties from java.lang.System.getProperties(), parsed and converted as with parseProperties(Properties).

This method can return a global immutable singleton, so it's preferred over parsing system properties yourself.

ConfigFactory.load() will include the system properties as overrides already, as will defaultReference() and defaultOverrides().

Because this returns a singleton, it will not notice changes to system properties made after the first time this method is called. Use invalidateCaches() to force the singleton to reload if you modify system properties.