org.yarnandtail.andhow.load

Class KeyValuePairLoader

java.lang.Object

org.yarnandtail.andhow.load.BaseLoader

org.yarnandtail.andhow.load.KeyValuePairLoader

All Implemented Interfaces:

Loader, ReadLoader

Direct Known Subclasses:

StdMainStringArgsLoader

public class KeyValuePairLoader
extends BaseLoader
implements ReadLoader

Intended to reads properties from the command line, but could be used for other sources where properties can be passed as an array of strings, each of the form name=value. This loader trims incoming values for String type properties using the Trimmer of the associated Property. This loader considers it a problem to find unrecognized properties on the command line and will throw a RuntimeException if that happens. For FlgProp properties (flags), the KeyValuePairLoader will interpret the presence of the property name as setting the property true. The JVM considers whitespace as breaks between values, however, it can be escaped with a backslash to include it in the value passed to the KeyValuePairLoader. After the KeyValuePairLoader receives the value, each individual Property will use its Trimmer to remove whitespace according to its own rules. Generally that means the QuotedSpacePreservingTrimmer for strings and the TrimToNullTrimmer for everything else.

Author:

eeverman

Field Summary

Fields

Modifier and Type	Field and Description
static String	KVP_DELIMITER The default delimiter between a key and a value.
protected boolean	unknownPropertyAProblem

Constructor Summary

Constructors

Constructor and Description
KeyValuePairLoader()

Method Summary

Modifier and Type	Method and Description
String	getLoaderDialect() The type dialect of the loader.
String	getLoaderType() The type of the loader, such as JNDI, PropertyFile, SystemProperty, etc..
String	getSpecificLoadDescription() For this particular load, where was info loaded from? This may vary from run to run based on config params.
boolean	isTrimmingRequiredForStringValues() If true, values for string properties are trimmed by the Trimmer of the property they are associated with.
boolean	isUnknownPropertyAProblem() If true, an unrecognized name is considered a problem that will stop application startup.
LoaderValues	load(StaticPropertyConfiguration appConfigDef, ValidatedValuesWithContext existingValues) Builds up a list of LoaderValues by loading property values from a configuration source.
void	releaseResources() Release any resources held by this loader.
void	setKeyValuePairs(List<String> keyValuePairs) Sets the list of string arguments, each string containing a key-value pair or just a key for flag type values.
void	setKeyValuePairs(String... keyValuePairs) Sets the list of string arguments, each string containing a key-value pair or just a key for flag type values.
void	setUnknownPropertyAProblem(boolean isAProblem) If true, an unrecognized property name is considered a problem/error.

Methods inherited from class org.yarnandtail.andhow.load.BaseLoader

attemptToAdd, attemptToAdd, createValue, findDuplicateProperty, getClassConfig, getConfigSamplePrinter, getInstanceConfig

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.yarnandtail.andhow.api.Loader

getClassConfig, getConfigSamplePrinter, getInstanceConfig

Field Detail

unknownPropertyAProblem

protected boolean unknownPropertyAProblem

KVP_DELIMITER

public static final String KVP_DELIMITER

The default delimiter between a key and a value.

See Also:

Constant Field Values

Constructor Detail

KeyValuePairLoader

public KeyValuePairLoader()

Method Detail

setKeyValuePairs

public void setKeyValuePairs(List<String> keyValuePairs)

Sets the list of string arguments, each string containing a key-value pair or just a key for flag type values. Values are copied, so changes to the passed list are not tracked. KVPs are split by KVP.splitKVP using '=' as the delimiter, as defined in AndHow.KVP_DELIMITER.

Parameters:

keyValuePairs -

setKeyValuePairs

public void setKeyValuePairs(String... keyValuePairs)

Sets the list of string arguments, each string containing a key-value pair or just a key for flag type values. Values are copied, so changes to the passed array are not tracked. KVPs are split by KVP.splitKVP using '=' as the delimiter, as defined in AndHow.KVP_DELIMITER.

Parameters:

keyValuePairs -

load

public LoaderValues load(StaticPropertyConfiguration appConfigDef,
                         ValidatedValuesWithContext existingValues)

Description copied from interface: Loader

Builds up a list of LoaderValues by loading property values from a configuration source. Loaders find and load values and associate them with the correct Property. If there is a problem while doing that, they register one or more LoaderProblems in the returned LoaderValues. Validation of Property values is not Loader's responsibility and will be handled outside this method.

Specified by:

load in interface Loader

Returns:

getSpecificLoadDescription

public String getSpecificLoadDescription()

Description copied from interface: Loader

For this particular load, where was info loaded from? This may vary from run to run based on config params. For instance, The PropFileLoader will look multiple places to find a properties file. This method should return the actual location it was found. Assume the text is prefixed with "This loader loaded from: ". An example would be "/home/user/config/my-props.properties" No ending punctuation should be used.

Specified by:

getSpecificLoadDescription in interface Loader

Returns:

isTrimmingRequiredForStringValues

public boolean isTrimmingRequiredForStringValues()

Description copied from interface: Loader

If true, values for string properties are trimmed by the Trimmer of the property they are associated with. If false, no trimming is done. Non-String type property values (like Integer or Date type values) are not affected by this. Loaders that read from text files need to trim values to separate white space and carriage returns from the value. Loaders that read from more tightly defined sources, like reading properties from java.lang.System.getProperties(), can assume that trimming has already happened.

Specified by:

isTrimmingRequiredForStringValues in interface Loader

Returns:

getLoaderType

public String getLoaderType()

Description copied from interface: Loader

The type of the loader, such as JNDI, PropertyFile, SystemProperty, etc.. The actual return value is arbitrary, but should be consistent between loaders of the same type. The values returned by getLoaderType and getLoaderDialect are used to removed duplicate loader types when printing sample files. If two loader instances are of the same type and dialect, only one will print the sample file.

Specified by:

getLoaderType in interface Loader

Returns:

Must never returns null.

getLoaderDialect

public String getLoaderDialect()

Description copied from interface: Loader

The type dialect of the loader. For property files, this might be either KeyValuePair or xml for example. The actual return value is arbitrary, but should be consistent between loaders of the same type and dialect. The values returned by getLoaderType and getLoaderDialect are used to removed duplicate loader types when printing sample files. If two loader instances are of the same type and dialect, only one will print the sample file.

Specified by:

getLoaderDialect in interface Loader

Returns:

May return null if there is no meaningful dialect for this type.

setUnknownPropertyAProblem

public void setUnknownPropertyAProblem(boolean isAProblem)

Description copied from interface: ReadLoader

If true, an unrecognized property name is considered a problem/error.

Specified by:

setUnknownPropertyAProblem in interface ReadLoader

isUnknownPropertyAProblem

public boolean isUnknownPropertyAProblem()

Description copied from interface: ReadLoader

If true, an unrecognized name is considered a problem that will stop application startup. This is a safety feature because a unrecognized property name in a properties file could be a typo. For other property sources, however, like System.properties, there are many non-AndHow related values that are expected to be present, so this rule cannot be enforced.

Specified by:

isUnknownPropertyAProblem in interface ReadLoader

Returns:

releaseResources

public void releaseResources()

Description copied from interface: Loader

Release any resources held by this loader. Loaders have done their job after loading values to properties. However, they may be held in memory for auditing and reporting. To prevent holding additional resources in memory, this method is called after loading is complete.

Specified by:

releaseResources in interface Loader

Overrides:

releaseResources in class BaseLoader