org.yarnandtail.andhow

Class AndHow.AndHowBuilder

java.lang.Object

org.yarnandtail.andhow.AndHow.AndHowBuilder

Enclosing class:

AndHow

public static class AndHow.AndHowBuilder
extends Object

A builder class, which is the only supported way to construct an AndHow instance. Once an AndHow instance is built, it can never be rebuilt or reconfigured**., The builder code is intended to be concise and readable in use. Thus, 'set' or 'add' is dropped from method name prefixes where possible. For single valued properties, like namingStrategy, calling namingStrategy(new ANamingStrategy()) sets the value. For attributes that takes lists of of values, there are methods that add single values or multiple values, e.g. for PropertyGroups, calling builder.group(SomeGroup.class) would add a single group, builder.groups(aListOfGroups) would add an entire list. Usage always starts with AndHow.builder() and ends with build():

  
 		AndHow.builder()
			.loader(new PropFileLoader)
			.group(SomeGroup.class)
			.group(SomeOtherGroup.class)
			.cmdLineArgs([Array of cmd line arguments])
			.build();
 
 

There is no return value because there is no need to hold a reference to anything past framework startup. After a successful startup, Property values can be read directly. For instance, for a Property named 'MyInt': Integer value = MyInt.getValue(); Attempting to call build() a 2nd time will throw a RuntimeException, so it is important that a single entry and configuration loading point to your application is well defined. See buildForNonPropduction() for a small backdoor for unit testing, which provides a non-production, unsupported way to force the AndHow framework to reload its state.

Author:

eeverman

Constructor Summary

Constructors

Constructor and Description
AndHowBuilder()

Method Summary

Modifier and Type	Method and Description
void	build() Executes the AndHow framework startup.
AndHow.Reloader	buildForNonPropduction() Bootstraps the AndHow framework and returns a Reloader that can be used to destroy or reload the AndHow framework.
AndHow.AndHowBuilder	cmdLineArg(String key, String value) Adds a command line argument in key=value form.
AndHow.AndHowBuilder	cmdLineArgs(String[] commandLineArgs) Adds the command line arguments, keeping any previously added.
AndHow.AndHowBuilder	group(Class<? extends BasePropertyGroup> group) Add a group to the list of groups being built.
AndHow.AndHowBuilder	groups(Collection<Class<? extends BasePropertyGroup>> groups) Add a list of groups to the list of groups being built.
AndHow.AndHowBuilder	loader(Loader loader) Add a loader to the list of loaders.
AndHow.AndHowBuilder	loaders(Collection<Loader> loaders) Add a list of loaders to the list being built.
AndHow.AndHowBuilder	namingStrategy(NamingStrategy namingStrategy) Sets the naming strategy, which determines how the property names are realized when used in config files, JNDI and cmd line arguments.
void	reloadForNonPropduction(AndHow.Reloader reloader) After initial construction with buildForNonPropduction() this method forces a reload using the reloader instance.

Methods inherited from class java.lang.Object

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

Constructor Detail

AndHowBuilder

public AndHowBuilder()

Method Detail

loader

public AndHow.AndHowBuilder loader(Loader loader)

Add a loader to the list of loaders. Loaders are used in the order added.

Parameters:

loader -

Returns:

loaders

public AndHow.AndHowBuilder loaders(Collection<Loader> loaders)

Add a list of loaders to the list being built. Loaders are used in the order added.

Parameters:

loaders -

Returns:

group

public AndHow.AndHowBuilder group(Class<? extends BasePropertyGroup> group)

Add a group to the list of groups being built. Group order makes no difference, but for error reports and sample configuration files, the order is preserved.

Parameters:

group -

Returns:

groups

public AndHow.AndHowBuilder groups(Collection<Class<? extends BasePropertyGroup>> groups)

Add a list of groups to the list of groups being built. Group order makes no difference, but for error reports and sample configuration files, the order is preserved.

Parameters:

groups -

Returns:

cmdLineArgs

public AndHow.AndHowBuilder cmdLineArgs(String[] commandLineArgs)

Adds the command line arguments, keeping any previously added. Note that adding cmd line args implicitly add a StringArgumentLoader at the point in code where the first cmd line argument is added, thus determining the load order of cmd line arguments in relation to other loaders.

Parameters:

commandLineArgs -

Returns:

cmdLineArg

public AndHow.AndHowBuilder cmdLineArg(String key,
                                       String value)

Adds a command line argument in key=value form. If the value is null, only the key is added (ie its a flag).

Parameters:

key -

value -

Returns:

namingStrategy

public AndHow.AndHowBuilder namingStrategy(NamingStrategy namingStrategy)

Sets the naming strategy, which determines how the property names are realized when used in config files, JNDI and cmd line arguments. If unspecified, CaseInsensitiveNaming is used.

Parameters:

namingStrategy -

Returns:

build

public void build()
           throws AppFatalException

Executes the AndHow framework startup. There is no return value because there is no need to hold a reference to anything past framework startup. After a successful startup, Property values can be read directly. For instance, for a property named 'MyInt': Integer value = MyInt.getValue();

Throws:

AppFatalException - If the startup fails.

buildForNonPropduction

public AndHow.Reloader buildForNonPropduction()
                                       throws AppFatalException

Bootstraps the AndHow framework and returns a Reloader that can be used to destroy or reload the AndHow framework. Destroying or reloading is strictly for testing - Support for reloading, including dealing with the issue of inconsistent reads of the data, is not in place. Don't use this method in production, just use build(), which doesn't return the reloader. This method may be removed in a future version. You have been warned.

Returns:

Throws:

AppFatalException

reloadForNonPropduction

public void reloadForNonPropduction(AndHow.Reloader reloader)
                             throws AppFatalException

After initial construction with buildForNonPropduction() this method forces a reload using the reloader instance. Not for production, @See buildForNonPropduction

Parameters:

reloader - Must be the same instance given out by buildForNonPropduction.

Throws:

AppFatalException