org.apache.commons.crypto.utils

Class Utils

java.lang.Object

org.apache.commons.crypto.utils.Utils

public final class Utils
extends Object

General utility methods.

Method Summary

Modifier and Type	Method and Description
static void	checkArgument(boolean expression) Ensures the truth of an expression involving one or more parameters to the calling method.
static void	checkArgument(boolean expression, Object errorMessage) Checks the truth of an expression.
static <T> T	checkNotNull(T reference) Deprecated. Use Objects.requireNonNull(Object).
static void	checkState(boolean expression) Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
static void	checkState(boolean expression, String message) Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
static CryptoCipher	getCipherInstance(String transformation, Properties properties) Helper method to create a CryptoCipher instance and throws only IOException.
static Properties	getDefaultProperties() Gets a properties instance that defaults to the System Properties plus any other properties found in the file SYSTEM_PROPERTIES_FILE
static Properties	getProperties(Properties newProp) Gets the properties merged with default properties.
static List<String>	splitClassNames(String clazzNames, String separator) Splits class names sequence into substrings, Trim each substring into an entry,and returns an list of the entries.

Methods inherited from class java.lang.Object

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

Method Detail

checkArgument

public static void checkArgument(boolean expression)

Ensures the truth of an expression involving one or more parameters to the calling method.

Parameters:

expression - a boolean expression.

Throws:

IllegalArgumentException - if expression is false.

checkArgument

public static void checkArgument(boolean expression,
                                 Object errorMessage)

Checks the truth of an expression.

Parameters:

expression - a boolean expression.

errorMessage - the exception message to use if the check fails; will be converted to a string using String .valueOf(Object).

Throws:

IllegalArgumentException - if expression is false.

checkNotNull

@Deprecated
public static <T> T checkNotNull(T reference)

Deprecated. Use Objects.requireNonNull(Object).

Ensures that an object reference passed as a parameter to the calling method is not null.

Type Parameters:

T - the type of the object reference to be checked.

Parameters:

reference - an object reference.

Returns:

the non-null reference that was validated.

Throws:

NullPointerException - if reference is null.

checkState

public static void checkState(boolean expression)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

Parameters:

expression - a boolean expression.

Throws:

IllegalStateException - if expression is false.

checkState

public static void checkState(boolean expression,
                              String message)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

Parameters:

expression - a boolean expression.

message - Error message for the exception when the expression is false.

Throws:

IllegalStateException - if expression is false.

getCipherInstance

public static CryptoCipher getCipherInstance(String transformation,
                                             Properties properties)
                                      throws IOException

Helper method to create a CryptoCipher instance and throws only IOException.

Parameters:

properties - The Properties class represents a set of properties.

transformation - the name of the transformation, e.g., AES/CBC/PKCS5Padding. See the Java Cryptography Architecture Standard Algorithm Name Documentation for information about standard transformation names.

Returns:

the CryptoCipher instance.

Throws:

IOException - if an I/O error occurs.

getDefaultProperties

public static Properties getDefaultProperties()

Gets a properties instance that defaults to the System Properties plus any other properties found in the file SYSTEM_PROPERTIES_FILE

Returns:

a Properties instance with defaults

getProperties

public static Properties getProperties(Properties newProp)

Gets the properties merged with default properties.

Parameters:

newProp - User-defined properties

Returns:

User-defined properties with the default properties

splitClassNames

public static List<String> splitClassNames(String clazzNames,
                                           String separator)

Splits class names sequence into substrings, Trim each substring into an entry,and returns an list of the entries.

Parameters:

clazzNames - a string consist of a list of the entries joined by a delimiter, may be null or empty in which case an empty list is returned.

separator - a delimiter for the input string.

Returns:

a list of class entries.