Package it.tidalwave.util

Class Parameters

java.lang.Object

it.tidalwave.util.Parameters

public final class Parameters
extends java.lang.Object

This class provides a few static utility methods to manipulate arguments to methods.

Author:

Fabrizio Giudici

Status: stable API

Constructor Summary

Constructors

Constructor	Description
Parameters()

Method Summary

Modifier and Type	Method	Description
static <T> java.util.Collection<T>	find(java.lang.Class<T> parameterClass, java.lang.Object... parameters)	Extracts multiple-value parameters of the given type from an array.
static <T> T	find(java.lang.Class<T> parameterClass, T defaultOption, java.lang.Object... parameters)	Extracts a singled-value parameter of the given type from an array.
static java.lang.Object	mustNotBeArrayOrCollection(java.lang.Object object, java.lang.String message)	This method is for internal implementation only. Ensures that a given object is neither an array nor a collection.
static java.util.Collection<java.lang.Object>	r(java.lang.Object... roles)	A convenience method for transforming a varargs of roles to a Collection.

Methods inherited from class java.lang.Object

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

Constructor Detail

Parameters

public Parameters()

Method Detail

r

@Nonnull
public static java.util.Collection<java.lang.Object> r(@Nonnull
                                                       java.lang.Object... roles)

A convenience method for transforming a varargs of roles to a Collection. It supports concatenating collections: that is, each varargs item that is a Collection is flattened.

Parameters:

roles - the roles as varargs

Returns:

the roles as collection

Since:

3.2-ALPHA-3

find

@CheckForNull
public static <T> T find(@Nonnull
                         java.lang.Class<T> parameterClass,
                         @CheckForNull
                         T defaultOption,
                         @Nonnull
                         java.lang.Object... parameters)
                  throws java.lang.IllegalArgumentException

Extracts a singled-value parameter of the given type from an array. If the parameter is not found, the default value is returned. If more than a single parameter is found, an IllegalArgumentException is thrown.

Type Parameters:

T - the static type of the parameter

Parameters:

parameterClass - the dynamic type of the parameter

defaultOption - the default value of the parameter

parameters - the array of parameters

Returns:

the value of the parameter

Throws:

java.lang.IllegalArgumentException - if more than a single value is found

find

@Nonnull
public static <T> java.util.Collection<T> find(@Nonnull
                                               java.lang.Class<T> parameterClass,
                                               @Nonnull
                                               java.lang.Object... parameters)

Extracts multiple-value parameters of the given type from an array. If the parameter is not found, an empty collection is returned.

Type Parameters:

T - the static type of the parameter

Parameters:

parameterClass - the class of the parameter to retrieve

parameters - the array of parameters

Returns:

the value of the parameter

mustNotBeArrayOrCollection

@Nonnull
public static java.lang.Object mustNotBeArrayOrCollection(@Nonnull
                                                          java.lang.Object object,
                                                          @Nonnull
                                                          java.lang.String message)

This method is for internal implementation only. Ensures that a given object is neither an array nor a collection.

Parameters:

object - the object to check

message - the message to put in the exception

Returns:

the object itself for calling this method as a function