/*
    * 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 &gt; 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 &gt; 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 &gt; 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 &gt; 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 &gt; 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 );
             }
         }
     }
 }