Package dev.zemco.codegame.util

Class Preconditions

java.lang.Object

dev.zemco.codegame.util.Preconditions

public final class Preconditions
extends Object

Collection of utility functions for checking validity of arguments.

Author:

Erik Zemčík

Method Summary

Modifier and Type	Method	Description
static String	checkArgumentNotEmpty(String argument, String argumentName)	Throws formatted IllegalArgumentException if String argument is null or has no characters.
static <T extends Collection<?>> T	checkArgumentNotEmpty(T argument, String argumentName)	Throws formatted IllegalArgumentException if Collection argument is null or contains no elements.
static <T> T	checkArgumentNotNull(T argument, String argumentName)	Throws formatted IllegalArgumentException if argument is null.
static int	checkArgumentPositiveInteger(int argument, String argumentName)	Throws formatted IllegalArgumentException if argument is less than 0.

Methods inherited from class java.lang.Object

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

Method Details

checkArgumentNotNull

public static <T> T checkArgumentNotNull(T argument,
 String argumentName)

Throws formatted IllegalArgumentException if argument is null.

Type Parameters:

T - argument type

Parameters:

argument - argument to check

argumentName - name of the checked argument

Returns:

non-null instance passed to argument

Throws:

IllegalArgumentException - if argument is null

checkArgumentNotEmpty

public static String checkArgumentNotEmpty(String argument,
 String argumentName)

Throws formatted IllegalArgumentException if String argument is null or has no characters.

Parameters:

argument - argument to check

argumentName - name of the checked argument

Returns:

instance passed to argument

Throws:

IllegalArgumentException - if argument is null or empty

checkArgumentNotEmpty

public static <T extends Collection<?>> T checkArgumentNotEmpty(T argument,
 String argumentName)

Throws formatted IllegalArgumentException if Collection argument is null or contains no elements.

Type Parameters:

T - collection argument type

Parameters:

argument - argument to check

argumentName - name of the checked argument

Returns:

instance passed to argument

Throws:

IllegalArgumentException - if argument is null or empty

checkArgumentPositiveInteger

public static int checkArgumentPositiveInteger(int argument,
 String argumentName)

Throws formatted IllegalArgumentException if argument is less than 0.

Parameters:

argument - argument to check

argumentName - name of the checked argument

Returns:

int passed to argument

Throws:

IllegalArgumentException - if argument is less than 0