au.gov.nehta.common.utils

Class ArgumentUtils

java.lang.Object

au.gov.nehta.common.utils.ArgumentUtils

public final class ArgumentUtils
extends Object

Utility class to perform validation on method arguments.

Public and protected methods should throw an exception if invalid arguments are passed to them. This class has convenience methods for commonly-used checks.

Example Usage:

 public void doSomething(String name) {
   ArgumentUtils.checkNotNullNorBlank(name, "name");
   ...
 }
 

Method Summary

Modifier and Type	Method and Description
static void	checkMaxLength(String value, int maxLen, String name) Check that the length of a string does not exceed a max length.
static void	checkNotNull(Object value, String name) Throws an exception if an argument value is null.
static void	checkNotNullNorBlank(String value, String name) Throws an exception if a string argument is null, is an empty string or is made of whitespace characters only.
static void	checkNotNullNorEmpty(Collection<?> collection, String name) Throws an exception if a collection argument is null or has no items.
static void	checkNullOrBlank(String value, String name) Check that an argument is blank (null or empty string).
static boolean	isEqual(Object value1, Object value2) Checks two arguments for equality, handling nulls.
static boolean	isNullOrBlank(String value) Checks if a string argument is null or has no non-whitespace characters.
static boolean	isNullOrEmpty(Collection<?> collection) Checks if a collection argument is null or has no items.

Methods inherited from class java.lang.Object

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

Method Detail

checkNotNull

public static void checkNotNull(Object value,
                                String name)

Throws an exception if an argument value is null.

Parameters:

value - Value of the argument to check.

name - Name of the argument.

Throws:

IllegalArgumentException - If the argument is null.

checkNotNullNorEmpty

public static void checkNotNullNorEmpty(Collection<?> collection,
                                        String name)

Throws an exception if a collection argument is null or has no items.

Parameters:

collection - A collection to check.

name - Name of the collection argument.

Throws:

NullPointerException - If the collection argument is null.

IllegalArgumentException - If the collection argument does not contain at least one item.

checkNotNullNorBlank

public static void checkNotNullNorBlank(String value,
                                        String name)

Throws an exception if a string argument is null, is an empty string or is made of whitespace characters only.

Parameters:

value - Value of the string argument to check.

name - Name of the string argument.

Throws:

NullPointerException - If the string argument is null.

IllegalArgumentException - If the string argument is an empty string or is made of whitespace characters only.

checkNullOrBlank

public static void checkNullOrBlank(String value,
                                    String name)

Check that an argument is blank (null or empty string).

Parameters:

value - Value of the string argument to check.

name - Name of the string argument.

Throws:

IllegalArgumentException - If the value argument is not null or an empty string.

checkMaxLength

public static void checkMaxLength(String value,
                                  int maxLen,
                                  String name)

Check that the length of a string does not exceed a max length.

Parameters:

value - Value of the string argument to check.

maxLen - Maximum length of the string argument.

name - Name of the string argument.

Throws:

IllegalArgumentException - Exception to notify of max length being exceeded.

isNullOrEmpty

public static boolean isNullOrEmpty(Collection<?> collection)

Checks if a collection argument is null or has no items.

Parameters:

collection - collection to check.

Returns:

true if collection is collection is null or has no items.

isNullOrBlank

public static boolean isNullOrBlank(String value)

Checks if a string argument is null or has no non-whitespace characters.

Parameters:

value - string value to check.

Returns:

true if collection is collection is null or has no items.

isEqual

public static boolean isEqual(Object value1,
                              Object value2)

Checks two arguments for equality, handling nulls.

Parameters:

value1 - first argument to check.

value2 - second argument to check.

Returns:

true if the two objects are both null or value1.equals(value2) returns true.