org.apache.deltaspike.core.api.config

Class ConfigResolver

java.lang.Object

org.apache.deltaspike.core.api.config.ConfigResolver

@Typed
public final class ConfigResolver
extends Object

The main entry point to the DeltaSpike configuration mechanism.

Resolves configured values of properties by going through the list of configured ConfigSources and using the one with the highest ordinal. If multiple ConfigSources have the same ordinal, their order is undefined.

You can provide your own lookup paths by implementing and registering additional PropertyFileConfig or ConfigSource or ConfigSourceProvider implementations.

The resolved configuration is also accessible by simple injection using the ConfigProperty qualifier.

See Also:

DeltaSpike Configuration Mechanism

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	ConfigResolver.ConfigChanged<T> Callback which can be used with TypedResolver#onChange(ConfigChanged)
static interface	ConfigResolver.ConfigHelper Some utility functions which are useful for implementing own ConfigSources, etc.
static interface	ConfigResolver.ConfigProvider Provide access to the underlying Config instance.
static interface	ConfigResolver.Converter<T> A very simple interface for conversion of configuration values from String to any Java type.
static interface	ConfigResolver.TypedResolver<T> A builder-based typed resolution mechanism for configuration values.
static interface	ConfigResolver.UntypedResolver<T> A builder-based optionally typed resolution mechanism for configuration values.

Field Summary

Fields

Modifier and Type	Field and Description
static String	DELTASPIKE_APP_NAME_CONFIG Can be used to tweak the application name.
static String	DELTASPIKE_LOG_CONFIG Set this to true if your application should log the whole ConfigSources and Configuration at startup.

Method Summary

Modifier and Type	Method and Description
static void	addConfigFilter(ConfigFilter configFilter) Add a ConfigFilter to the ConfigResolver.
static void	addConfigSources(List<ConfigSource> configSourcesToAdd) This method can be used for programmatically adding ConfigSources.
static String	filterConfigValue(String key, String value) Filter the configured value.
static String	filterConfigValueForLog(String key, String value) Filter the configured value for logging.
static void	freeConfigSources() Clear all ConfigSources for the current ClassLoader.
static Map<String,String>	getAllProperties() Returns a Map of all properties from all scannable config sources.
static List<String>	getAllPropertyValues(String key) Resolve all values for the given key.
static Config	getConfig()
static Config	getConfig(ClassLoader cl)
static List<ConfigFilter>	getConfigFilters()
static ConfigResolver.ConfigProvider	getConfigProvider()
static ConfigSource[]	getConfigSources()
static String	getProjectStageAwarePropertyValue(String key) Resolves the value configured for the given key in the current ProjectStage.
static String	getProjectStageAwarePropertyValue(String key, String defaultValue) getProjectStageAwarePropertyValue(String) which returns the provided default value if no configured value can be found (null or empty).
static String	getPropertyAwarePropertyValue(String key, String property) Resolves the value configured for the given key, parameterized by the current ProjectStage and by the value of a second property.
static String	getPropertyAwarePropertyValue(String key, String property, String defaultValue) getPropertyAwarePropertyValue(java.lang.String, java.lang.String) which returns the provided default value if no configured value can be found (null or empty).
static String	getPropertyValue(String key) Resolves the value configured for the given key.
static String	getPropertyValue(String key, boolean evaluateVariables) Resolves the value configured for the given key.
static String	getPropertyValue(String key, String defaultValue) getPropertyValue(java.lang.String) which returns the provided default value if no configured value can be found (null or empty).
static String	getPropertyValue(String key, String defaultValue, boolean evaluateVariables)
static ConfigResolver.UntypedResolver<String>	resolve(String name) The entry point to the builder-based optionally typed configuration resolution mechanism.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DELTASPIKE_APP_NAME_CONFIG

public static final String DELTASPIKE_APP_NAME_CONFIG

Can be used to tweak the application name. This will e.g. used in the JMX MBean to differentiate between applications.

See Also:

Constant Field Values

DELTASPIKE_LOG_CONFIG

public static final String DELTASPIKE_LOG_CONFIG

Set this to true if your application should log the whole ConfigSources and Configuration at startup.

See Also:

Constant Field Values

Method Detail

getConfig

public static Config getConfig()

getConfig

public static Config getConfig(ClassLoader cl)

addConfigSources

public static void addConfigSources(List<ConfigSource> configSourcesToAdd)

This method can be used for programmatically adding ConfigSources. It is not needed for normal 'usage' by end users, but only for Extension Developers!

Parameters:

configSourcesToAdd - the ConfigSources to add

freeConfigSources

public static void freeConfigSources()

Clear all ConfigSources for the current ClassLoader. This will also clean up all ConfigFilters.

addConfigFilter

public static void addConfigFilter(ConfigFilter configFilter)

Add a ConfigFilter to the ConfigResolver. This will only affect the current WebApp (or more precisely the current ClassLoader and it's children).

Parameters:

configFilter -

getConfigFilters

public static List<ConfigFilter> getConfigFilters()

Returns:

the ConfigFilters for the current application.

getPropertyValue

public static String getPropertyValue(String key,
                                      String defaultValue)

getPropertyValue(java.lang.String) which returns the provided default value if no configured value can be found (null or empty).

Parameters:

key - the property key

defaultValue - fallback value

Returns:

the configured property value from the ConfigSource with the highest ordinal or the defaultValue if there is no value explicitly configured

getPropertyValue

public static String getPropertyValue(String key,
                                      String defaultValue,
                                      boolean evaluateVariables)

getPropertyValue

public static String getPropertyValue(String key)

Resolves the value configured for the given key.

Parameters:

key - the property key

Returns:

the configured property value from the ConfigSource with the highest ordinal or null if there is no configured value for it

getPropertyValue

public static String getPropertyValue(String key,
                                      boolean evaluateVariables)

Resolves the value configured for the given key.

Parameters:

key - the property key

evaluateVariables - whether to evaluate any '${variablename}' variable expressions

Returns:

the configured property value from the ConfigSource with the highest ordinal or null if there is no configured value for it

getProjectStageAwarePropertyValue

public static String getProjectStageAwarePropertyValue(String key)

Resolves the value configured for the given key in the current ProjectStage.

First, it will search for a value configured for the given key suffixed with the current ProjectStage (e.g. 'myproject.myconfig.Production'), and in case this value is not found (null or empty), it will look up the given key without any suffix.

Attention This method must only be used after all ConfigSources got registered and it also must not be used to determine the ProjectStage itself.

Parameters:

key -

Returns:

the value configured for <given key>.<current project stage>, or just the configured value of <given key> if the project-stage-specific value is not found (null or empty)

getProjectStageAwarePropertyValue

public static String getProjectStageAwarePropertyValue(String key,
                                                       String defaultValue)

getProjectStageAwarePropertyValue(String) which returns the provided default value if no configured value can be found (null or empty).

Parameters:

key -

defaultValue - fallback value

Returns:

the configured value or if non found the defaultValue

getPropertyAwarePropertyValue

public static String getPropertyAwarePropertyValue(String key,
                                                   String property)

Resolves the value configured for the given key, parameterized by the current ProjectStage and by the value of a second property.

Example:
Suppose the current ProjectStage is UnitTest and we are looking for the value of datasource parameterized by the configured dbvendor.

The first step is to resolve the value of the second property, dbvendor. This will also take the current ProjectStage into account. The following lookup is performed:

• dbvendor.UnitTest

and if this value is not found then we will do a 2nd lookup for

• dbvendor

If a value was found for the second property (e.g. dbvendor = 'mysql') then we will use its value for the main lookup. If no value is found for the parameterized key <key>.<second property value>.<project stage>, we will do the <key>.<second property value>, then <key>.<project stage> and finally a <key> lookup:

• datasource.mysql.UnitTest
• datasource.mysql
• datasource.UnitTest
• datasource

Attention This method must only be used after all ConfigSources got registered and it also must not be used to determine the ProjectStage itself.

Parameters:

key -

property - the property to look up first and use as the parameter for the main lookup

Returns:

the configured value or null if no value is found for any of the key variants

getPropertyAwarePropertyValue

public static String getPropertyAwarePropertyValue(String key,
                                                   String property,
                                                   String defaultValue)

getPropertyAwarePropertyValue(java.lang.String, java.lang.String) which returns the provided default value if no configured value can be found (null or empty).

Attention This method must only be used after all ConfigSources got registered and it also must not be used to determine the ProjectStage itself.

Parameters:

key -

property - the property to look up first and use as the parameter for the main lookup

defaultValue - fallback value

Returns:

the configured value or if non found the defaultValue

getAllPropertyValues

public static List<String> getAllPropertyValues(String key)

Resolve all values for the given key.

Parameters:

key -

Returns:

a List of all found property values, sorted by their ordinal in ascending order

See Also:

ConfigSource.getOrdinal()

getAllProperties

public static Map<String,String> getAllProperties()

Returns a Map of all properties from all scannable config sources. The values of the properties reflect the values that would be obtained by a call to getPropertyValue(java.lang.String), that is, the value of the property from the ConfigSource with the highest ordinal.

See Also:

ConfigSource.isScannable()

getConfigSources

public static ConfigSource[] getConfigSources()

filterConfigValue

public static String filterConfigValue(String key,
                                       String value)

Filter the configured value. This can e.g. be used for decryption.

Returns:

the filtered value

filterConfigValueForLog

public static String filterConfigValueForLog(String key,
                                             String value)

Filter the configured value for logging. This can e.g. be used for displaying ***** instead of a real password.

Returns:

the filtered value

resolve

public static ConfigResolver.UntypedResolver<String> resolve(String name)

The entry point to the builder-based optionally typed configuration resolution mechanism. String is the default type for configuration entries and is not considered a 'type' by this resolver. Therefore an UntypedResolver is returned by this method. To convert the configuration value to another type, call ConfigResolver.UntypedResolver.as(Class).

Parameters:

name - The property key to resolve

Returns:

A builder for configuration resolution.

getConfigProvider

public static ConfigResolver.ConfigProvider getConfigProvider()