org.opencastproject.util

Class RequireUtil

java.lang.Object

org.opencastproject.util.RequireUtil

public final class RequireUtil
extends Object

Utility functions for handling common requirements.

Method Summary

Modifier and Type	Method and Description
static double	between(double value, double min, double max)
static int	min(int value, int min)
static long	min(long value, long min)
static String	notEmpty(String value, String valueName) The given value must not be null or empty.
static <A> A	notNull(A value, String valueName) The given value must not be null.
static String	nullOrNotEmpty(String value, String valueName) The value may be null but if it is not null it must not be of size 0.
static void	requireFalse(boolean expr, String exprName) Require an expression to be false.
static String	requireNotBlank(String value, String valueName) The given string value must not be blank, empty nor null.
static void	requireTrue(boolean expr, String exprName) Require an expression to hold true.

Methods inherited from class java.lang.Object

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

Method Detail

requireTrue

public static void requireTrue(boolean expr,
                               String exprName)

Require an expression to hold true.

Parameters:

expr - the expression

exprName - the name of the expression used to create an error message in case expr evaluates to false

Throws:

IllegalArgumentException - in case expr evaluates to false

requireFalse

public static void requireFalse(boolean expr,
                                String exprName)

Require an expression to be false.

Parameters:

expr - the expression

exprName - the name of the expression used to create an error message in case expr evaluates to false

Throws:

IllegalArgumentException - in case expr evaluates to true

notNull

public static <A> A notNull(A value,
                            String valueName)

The given value must not be null.

Example:

 class A {
   private String a;

   A(String a) {
     this.a = notNull(a, "a");
   }
 }
 

Parameters:

value - the value to check for null

valueName - the name of the value; used in error message

Returns:

the value, if it is not null

Throws:

IllegalArgumentException - in case of value being null

notEmpty

public static String notEmpty(String value,
                              String valueName)

The given value must not be null or empty.

Example:

 class A {
   private String a;

   A(String a) {
     this.a = notEmpty(a, "a");
   }
 }
 

Parameters:

value - the value to check for emptiness

valueName - the name of the value; used in error message

Returns:

the value, if it is not empty

Throws:

IllegalArgumentException - in case of value being empty

requireNotBlank

public static String requireNotBlank(String value,
                                     String valueName)

The given string value must not be blank, empty nor null. Otherwise, an IllegalArgumentException is thrown.

Parameters:

value - the value to check for not being empty

valueName - the name of the value

Returns:

the value, if not blank

nullOrNotEmpty

public static String nullOrNotEmpty(String value,
                                    String valueName)

The value may be null but if it is not null it must not be of size 0.

between

public static double between(double value,
                             double min,
                             double max)

min

public static int min(int value,
                      int min)

min

public static long min(long value,
                       long min)