Validate.java
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.fulcrum.yaafi.framework.util;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;
import org.apache.commons.lang3.StringUtils;
/**
* <p>Assists in validating arguments.</p>
*
* <p>The class is based along the lines of JUnit. If an argument value is
* deemed invalid, an IllegalArgumentException is thrown. For example:</p>
*
* <pre>
* Validate.isTrue( i > 0, "The value must be greater than zero: ", i);
* Validate.notNull( surname, "The surname must not be null");
* </pre>
*
* @author <a href="mailto:ola.berg@arkitema.se">Ola Berg</a>
* @author Stephen Colebourne
* @author Gary Gregory
* @author Norm Deane
* @since 2.0
* @version $Id$
*/
public class Validate
{
/**
* Constructor. This class should not normally be instantiated.
*/
public Validate()
{
}
// isTrue
//---------------------------------------------------------------------------------
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the test result is <code>false</code>.</p>
*
* <p>This is used when validating according to an arbitrary boolean expression,
* such as validating a primitive number or using your own custom validation
* expression.</p>
*
* <pre>
* Validate.isTrue( myObject.isOk(), "The object is not OK: ", myObject);
* </pre>
*
* <p>For performance reasons, the object is passed as a separate parameter and
* appended to the message string only in the case of an error.</p>
*
* @param expression a boolean expression
* @param message the exception message you would like to see if the
* expression is <code>false</code>
* @param value the value to append to the message in case of error
* @throws IllegalArgumentException if expression is <code>false</code>
*/
public static void isTrue(boolean expression, String message, Object value)
{
if (expression == false)
{
throw new IllegalArgumentException( message + value );
}
}
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the test result is <code>false</code>.</p>
*
* <p>This is used when validating according to an arbitrary boolean expression,
* such as validating a primitive number or using your own custom validation
* expression.</p>
*
* <pre>
* Validate.isTrue( i > 0, "The value must be greater than zero: ", i);
* </pre>
*
* <p>For performance reasons, the long value is passed as a separate parameter and
* appended to the message string only in the case of an error.</p>
*
* @param expression a boolean expression
* @param message the exception message you would like to see if the expression is <code>false</code>
* @param value the value to append to the message in case of error
* @throws IllegalArgumentException if expression is <code>false</code>
*/
public static void isTrue(boolean expression, String message, long value)
{
if (expression == false)
{
throw new IllegalArgumentException( message + value );
}
}
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the test result is <code>false</code>.</p>
*
* <p>This is used when validating according to an arbitrary boolean expression,
* such as validating a primitive number or using your own custom validation
* expression.</p>
*
* <pre>
* Validate.isTrue( d > 0.0, "The value must be greater than zero: ", d);
* </pre>
*
* <p>For performance reasons, the double value is passed as a separate parameter and
* appended to the message string only in the case of an error.</p>
*
* @param expression a boolean expression
* @param message the exception message you would like to see if the expression
* is <code>false</code>
* @param value the value to append to the message in case of error
* @throws IllegalArgumentException if expression is <code>false</code>
*/
public static void isTrue(boolean expression, String message, double value)
{
if (expression == false)
{
throw new IllegalArgumentException( message + value );
}
}
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the test result is <code>false</code>.</p>
*
* <p>This is used when validating according to an arbitrary boolean expression,
* such as validating a primitive number or using your own custom validation
* expression.</p>
*
* <pre>
* Validate.isTrue( (i > 0), "The value must be greater than zero");
* Validate.isTrue( myObject.isOk(), "The object is not OK");
* </pre>
*
* <p>For performance reasons, the message string should not involve a string append,
* instead use the {@link #isTrue(boolean, String, Object)} method.</p>
*
* @param expression a boolean expression
* @param message the exception message you would like to see if the expression
* is <code>false</code>
* @throws IllegalArgumentException if expression is <code>false</code>
*/
public static void isTrue(boolean expression, String message)
{
if (expression == false)
{
throw new IllegalArgumentException( message );
}
}
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the test result is <code>false</code>.</p>
*
* <p>This is used when validating according to an arbitrary boolean expression,
* such as validating a primitive number or using your own custom validation
* expression.</p>
*
* <pre>
* Validate.isTrue( i > 0 );
* Validate.isTrue( myObject.isOk() );
* </pre>
*
* <p>The message in the exception is 'The validated expression is false'.</p>
*
* @param expression a boolean expression
* @throws IllegalArgumentException if expression is <code>false</code>
*/
public static void isTrue(boolean expression)
{
if (expression == false)
{
throw new IllegalArgumentException(
"The validated expression is false" );
}
}
// notNull
//---------------------------------------------------------------------------------
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument is <code>null</code>.</p>
*
* <pre>
* Validate.notNull(myObject, "The object must not be null");
* </pre>
*
* @param object the object to check is not <code>null</code>
* @param message the exception message you would like to see
* if the object is <code>null</code>
* @throws IllegalArgumentException if the object is <code>null</code>
*/
public static void notNull(Object object, String message)
{
if (object == null)
{
throw new IllegalArgumentException( message );
}
}
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument is <code>null</code>.</p>
*
* <pre>
* Validate.notNull(myObject);
* </pre>
*
* <p>The message in the exception is 'The validated object is null'.</p>
*
* @param object the object to check is not <code>null</code>
* @throws IllegalArgumentException if the object is <code>null</code>
*/
public static void notNull(Object object)
{
if (object == null)
{
throw new IllegalArgumentException( "The validated object is null" );
}
}
// notEmpty array
//---------------------------------------------------------------------------------
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument array is empty (<code>null</code> or no elements).</p>
*
* <pre>
* Validate.notEmpty(myArray, "The array must not be empty");
* </pre>
*
* @param array the array to check is not empty
* @param message the exception message you would like to see if the array is empty
* @throws IllegalArgumentException if the array is empty
*/
public static void notEmpty(Object [] array, String message)
{
if (array == null || array.length == 0)
{
throw new IllegalArgumentException( message );
}
}
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument array is empty (<code>null</code> or no elements).</p>
*
* <pre>
* Validate.notEmpty(myArray);
* </pre>
*
* <p>The message in the exception is 'The validated array is empty'.
*
* @param array the array to check is not empty
* @throws IllegalArgumentException if the array is empty
*/
public static void notEmpty(Object [] array)
{
if (array == null || array.length == 0)
{
throw new IllegalArgumentException( "The validated array is empty" );
}
}
// notEmpty collection
//---------------------------------------------------------------------------------
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument Collection is empty (<code>null</code> or no elements).</p>
*
* <pre>
* Validate.notEmpty(myCollection, "The collection must not be empty");
* </pre>
*
* @param collection the collection to check is not empty
* @param message the exception message you would like to see if the collection is empty
* @throws IllegalArgumentException if the collection is empty
*/
public static void notEmpty(Collection<?> collection, String message)
{
if (collection == null || collection.size() == 0)
{
throw new IllegalArgumentException( message );
}
}
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument Collection is empty (<code>null</code> or no elements).</p>
*
* <pre>
* Validate.notEmpty(myCollection);
* </pre>
*
* <p>The message in the exception is 'The validated collection is empty'.</p>
*
* @param collection the collection to check is not empty
* @throws IllegalArgumentException if the collection is empty
*/
public static void notEmpty(Collection<?> collection)
{
if (collection == null || collection.size() == 0)
{
throw new IllegalArgumentException(
"The validated collection is empty" );
}
}
// notEmpty map
//---------------------------------------------------------------------------------
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument Map is empty (<code>null</code> or no elements).</p>
*
* <pre>
* Validate.notEmpty(myMap, "The map must not be empty");
* </pre>
*
* @param map the map to check is not empty
* @param message the exception message you would like to see if the map is empty
* @throws IllegalArgumentException if the map is empty
*/
public static void notEmpty(Map<?, ?> map, String message)
{
if (map == null || map.size() == 0)
{
throw new IllegalArgumentException( message );
}
}
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument Map is empty (<code>null</code> or no elements).</p>
*
* <pre>
* Validate.notEmpty(myMap);
* </pre>
*
* <p>The message in the exception is 'The validated map is empty'.</p>
*
* @param map the map to check is not empty
* @throws IllegalArgumentException if the map is empty
*/
public static void notEmpty(Map<?, ?> map)
{
if (map == null || map.size() == 0)
{
throw new IllegalArgumentException( "The validated map is empty" );
}
}
// notEmpty string
//---------------------------------------------------------------------------------
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument String is empty (<code>null</code> or zero length).</p>
*
* <pre>
* Validate.notEmpty(myString, "The string must not be empty");
* </pre>
*
* @param string the string to check is not empty
* @param message the exception message you would like to see if the string is empty
* @throws IllegalArgumentException if the string is empty
*/
public static void notEmpty(String string, String message)
{
if ( StringUtils.isEmpty(string) )
throw new IllegalArgumentException( message );
}
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument String is empty (<code>null</code> or zero length).</p>
*
* <pre>
* Validate.notEmpty(myString);
* </pre>
*
* <p>The message in the exception is 'The validated string is empty'.</p>
*
* @param string the string to check is not empty
* @throws IllegalArgumentException if the string is empty
*/
public static void notEmpty(String string)
{
if ( StringUtils.isEmpty(string) )
throw new IllegalArgumentException( "The validated string is empty" );
}
// notNullElements array
//---------------------------------------------------------------------------------
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument array has <code>null</code> elements or is
* <code>null</code>.</p>
*
* <pre>
* Validate.noNullElements(myArray, "The array must not contain null elements");
* </pre>
*
* <p>If the array is null then the message in the exception is 'The validated object is null'.</p>
*
* @param array the array to check
* @param message the exception message if the array has
* <code>null</code> elements
* @throws IllegalArgumentException if the array has <code>null</code>
* elements or is <code>null</code>
*/
public static void noNullElements(Object [] array, String message)
{
Validate.notNull( array );
for (int i = 0; i < array.length; i++)
{
if (array[i] == null)
{
throw new IllegalArgumentException( message );
}
}
}
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument array has <code>null</code> elements or is
* <code>null</code>.</p>
*
* <pre>
* Validate.noNullElements(myArray);
* </pre>
*
* <p>If the array has a null element the message in the exception is
* 'The validated array contains null element at index: '.</p>
*
* <p>If the array is null then the message in the exception is 'The validated object is null'.</p>
*
* @param array the array to check
* @throws IllegalArgumentException if the array has <code>null</code>
* elements or is <code>null</code>
*/
public static void noNullElements(Object [] array)
{
Validate.notNull( array );
for (int i = 0; i < array.length; i++)
{
if (array[i] == null)
{
throw new IllegalArgumentException(
"The validated array contains null element at index: "
+ i );
}
}
}
// notNullElements collection
//---------------------------------------------------------------------------------
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument Collection has <code>null</code> elements or is
* <code>null</code>.</p>
*
* <pre>
* Validate.noNullElements(myCollection, "The collection must not contain null elements");
* </pre>
*
* <p>If the collection is null then the message in the exception is 'The validated object is null'.</p>
*
* @param collection the collection to check
* @param message the exception message if the collection has
* <code>null</code> elements
* @throws IllegalArgumentException if the collection has
* <code>null</code> elements or is <code>null</code>
*/
public static void noNullElements(Collection<?> collection, String message)
{
Validate.notNull( collection );
for (Iterator<?> it = collection.iterator(); it.hasNext();)
{
if (it.next() == null)
{
throw new IllegalArgumentException( message );
}
}
}
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument Collection has <code>null</code> elements or is
* <code>null</code>.</p>
*
* <pre>
* Validate.noNullElements(myCollection);
* </pre>
*
* <p>The message in the exception is 'The validated collection contains null element at index: '.</p>
*
* <p>If the collection is null then the message in the exception is 'The validated object is null'.</p>
*
* @param collection the collection to check
* @throws IllegalArgumentException if the collection has
* <code>null</code> elements or is <code>null</code>
*/
public static void noNullElements(Collection<?> collection)
{
Validate.notNull( collection );
int i = 0;
for (Iterator<?> it = collection.iterator(); it.hasNext(); i++)
{
if (it.next() == null)
{
throw new IllegalArgumentException(
"The validated collection contains null element at index: "
+ i );
}
}
}
/**
* <p>Validate an argument, throwing <code>IllegalArgumentException</code>
* if the argument collection is <code>null</code> or has elements that
* are not of type <code>clazz</code> or a subclass.</p>
*
* <pre>
* Validate.allElementsOfType(collection, String.class, "Collection has invalid elements");
* </pre>
*
* @param collection the collection to check, not null
* @param clazz the <code>Class</code> which the collection's elements are expected to be, not null
* @param message the exception message if the <code>Collection</code> has elements not of type <code>clazz</code>
* @since 2.1
*/
public static void allElementsOfType(Collection<?> collection, Class<?> clazz,
String message)
{
Validate.notNull( collection );
Validate.notNull( clazz );
for (Iterator<?> it = collection.iterator(); it.hasNext();)
{
if (clazz.isInstance( it.next() ) == false)
{
throw new IllegalArgumentException( message );
}
}
}
/**
* <p>
* Validate an argument, throwing <code>IllegalArgumentException</code> if the argument collection is
* <code>null</code> or has elements that are not of type <code>clazz</code> or a subclass.
* </p>
*
* <pre>
* Validate.allElementsOfType(collection, String.class);
* </pre>
*
* <p>
* The message in the exception is 'The validated collection contains an element not of type clazz at index: '.
* </p>
*
* @param collection
* the collection to check, not null
* @param clazz
* the <code>Class</code> which the collection's elements are expected to be, not null
* @since 2.1
*/
public static void allElementsOfType(Collection<?> collection, Class<?> clazz)
{
Validate.notNull( collection );
Validate.notNull( clazz );
int i = 0;
for (Iterator<?> it = collection.iterator(); it.hasNext(); i++)
{
if (clazz.isInstance( it.next() ) == false)
{
throw new IllegalArgumentException(
"The validated collection contains an element not of type "
+ clazz.getName()
+ " at index: " + i );
}
}
}
}