Start line:  
End line:  

Snippet Preview

Snippet HTML Code

Stack Overflow Questions
  /*
   * 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.commons.lang;
 
 import java.util.Map;

Assists in validating arguments.

The class is based along the lines of JUnit. If an argument value is deemed invalid, an IllegalArgumentException is thrown. For example:

 Validate.isTrue( i > 0, "The value must be greater than zero: ", i);
 Validate.notNull( surname, "The surname must not be null");
 

Author(s):
Ola Berg
Stephen Colebourne
Gary Gregory
Norm Deane
Version:
$Id: Validate.java 437554 2006-08-28 06:21:41Z bayard $
Since:
2.0
 
 public class Validate {
     // Validate has no dependencies on other classes in Commons Lang at present
     
    
Constructor. This class should not normally be instantiated.
 
     public Validate() {
       super();
     }
     
     // isTrue
     //---------------------------------------------------------------------------------
 
    

Validate an argument, throwing IllegalArgumentException if the test result is false.

This is used when validating according to an arbitrary boolean expression, such as validating a primitive number or using your own custom validation expression.

 Validate.isTrue( myObject.isOk(), "The object is not OK: ", myObject);
 

For performance reasons, the object is passed as a separate parameter and appended to the message string only in the case of an error.

Parameters:
expression a boolean expression
message the exception message you would like to see if the expression is false
value the value to append to the message in case of error
Throws:
java.lang.IllegalArgumentException if expression is false
 
     public static void isTrue(boolean expressionString messageObject value) {
         if (expression == false) {
             throw new IllegalArgumentException(message + value);
         }
     }

    

Validate an argument, throwing IllegalArgumentException if the test result is false.

This is used when validating according to an arbitrary boolean expression, such as validating a primitive number or using your own custom validation expression.

 Validate.isTrue( i > 0, "The value must be greater than zero: ", i);
 

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.

Parameters:
expression a boolean expression
message the exception message you would like to see if the expression is false
value the value to append to the message in case of error
Throws:
java.lang.IllegalArgumentException if expression is false
    public static void isTrue(boolean expressionString messagelong value) {
        if (expression == false) {
            throw new IllegalArgumentException(message + value);
        }
    }

    

Validate an argument, throwing IllegalArgumentException if the test result is false.

This is used when validating according to an arbitrary boolean expression, such as validating a primitive number or using your own custom validation expression.

 Validate.isTrue( d > 0.0, "The value must be greater than zero: ", d);
 

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.

Parameters:
expression a boolean expression
message the exception message you would like to see if the expression is false
value the value to append to the message in case of error
Throws:
java.lang.IllegalArgumentException if expression is false
    public static void isTrue(boolean expressionString messagedouble value) {
        if (expression == false) {
            throw new IllegalArgumentException(message + value);
        }
    }

    

Validate an argument, throwing IllegalArgumentException if the test result is false.

This is used when validating according to an arbitrary boolean expression, such as validating a primitive number or using your own custom validation expression.

 Validate.isTrue( (i > 0), "The value must be greater than zero");
 Validate.isTrue( myObject.isOk(), "The object is not OK");
 

For performance reasons, the message string should not involve a string append, instead use the isTrue(boolean,java.lang.String,java.lang.Object) method.

Parameters:
expression a boolean expression
message the exception message you would like to see if the expression is false
Throws:
java.lang.IllegalArgumentException if expression is false
    public static void isTrue(boolean expressionString message) {
        if (expression == false) {
            throw new IllegalArgumentException(message);
        }
    }

    

Validate an argument, throwing IllegalArgumentException if the test result is false.

This is used when validating according to an arbitrary boolean expression, such as validating a primitive number or using your own custom validation expression.

 Validate.isTrue( i > 0 );
 Validate.isTrue( myObject.isOk() );
 

The message in the exception is 'The validated expression is false'.

Parameters:
expression a boolean expression
Throws:
java.lang.IllegalArgumentException if expression is false
    public static void isTrue(boolean expression) {
        if (expression == false) {
            throw new IllegalArgumentException("The validated expression is false");
        }
    }
    // notNull
    //---------------------------------------------------------------------------------

    

Validate an argument, throwing IllegalArgumentException if the argument is null.

 Validate.notNull(myObject, "The object must not be null");
 

Parameters:
object the object to check is not null
message the exception message you would like to see if the object is null
Throws:
java.lang.IllegalArgumentException if the object is null
    public static void notNull(Object objectString message) {
        if (object == null) {
            throw new IllegalArgumentException(message);
        }
    }

    

Validate an argument, throwing IllegalArgumentException if the argument is null.

 Validate.notNull(myObject);
 

The message in the exception is 'The validated object is null'.

Parameters:
object the object to check is not null
Throws:
java.lang.IllegalArgumentException if the object is null
    public static void notNull(Object object) {
        if (object == null) {
            throw new IllegalArgumentException("The validated object is null");
        }
    }
    // notEmpty array
    //---------------------------------------------------------------------------------

    

Validate an argument, throwing IllegalArgumentException if the argument array is empty (null or no elements).

 Validate.notEmpty(myArray, "The array must not be empty");
 

Parameters:
array the array to check is not empty
message the exception message you would like to see if the array is empty
Throws:
java.lang.IllegalArgumentException if the array is empty
    public static void notEmpty(Object[] arrayString message) {
        if (array == null || array.length == 0) {
            throw new IllegalArgumentException(message);
        }
    }

    

Validate an argument, throwing IllegalArgumentException if the argument array is empty (null or no elements).

 Validate.notEmpty(myArray);
 

The message in the exception is 'The validated array is empty'.

Parameters:
array the array to check is not empty
Throws:
java.lang.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
    //---------------------------------------------------------------------------------

    

Validate an argument, throwing IllegalArgumentException if the argument Collection is empty (null or no elements).

 Validate.notEmpty(myCollection, "The collection must not be empty");
 

Parameters:
collection the collection to check is not empty
message the exception message you would like to see if the collection is empty
Throws:
java.lang.IllegalArgumentException if the collection is empty
    public static void notEmpty(Collection collectionString message) {
        if (collection == null || collection.size() == 0) {
            throw new IllegalArgumentException(message);
        }
    }

    

Validate an argument, throwing IllegalArgumentException if the argument Collection is empty (null or no elements).

 Validate.notEmpty(myCollection);
 

The message in the exception is 'The validated collection is empty'.

Parameters:
collection the collection to check is not empty
Throws:
java.lang.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
    //---------------------------------------------------------------------------------

    

Validate an argument, throwing IllegalArgumentException if the argument Map is empty (null or no elements).

 Validate.notEmpty(myMap, "The map must not be empty");
 

Parameters:
map the map to check is not empty
message the exception message you would like to see if the map is empty
Throws:
java.lang.IllegalArgumentException if the map is empty
    public static void notEmpty(Map mapString message) {
        if (map == null || map.size() == 0) {
            throw new IllegalArgumentException(message);
        }
    }

    

Validate an argument, throwing IllegalArgumentException if the argument Map is empty (null or no elements).

 Validate.notEmpty(myMap);
 

The message in the exception is 'The validated map is empty'.

Parameters:
map the map to check is not empty
Throws:
java.lang.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
    //---------------------------------------------------------------------------------

    

Validate an argument, throwing IllegalArgumentException if the argument String is empty (null or zero length).

 Validate.notEmpty(myString, "The string must not be empty");
 

Parameters:
string the string to check is not empty
message the exception message you would like to see if the string is empty
Throws:
java.lang.IllegalArgumentException if the string is empty
    public static void notEmpty(String stringString message) {
        if (string == null || string.length() == 0) {
            throw new IllegalArgumentException(message);
        }
    }

    

Validate an argument, throwing IllegalArgumentException if the argument String is empty (null or zero length).

 Validate.notEmpty(myString);
 

The message in the exception is 'The validated string is empty'.

Parameters:
string the string to check is not empty
Throws:
java.lang.IllegalArgumentException if the string is empty
    public static void notEmpty(String string) {
        if (string == null || string.length() == 0) {
            throw new IllegalArgumentException("The validated string is empty");
        }
    }
    // notNullElements array
    //---------------------------------------------------------------------------------

    

Validate an argument, throwing IllegalArgumentException if the argument array has null elements or is null.

 Validate.noNullElements(myArray, "The array must not contain null elements");
 

If the array is null then the message in the exception is 'The validated object is null'.

Parameters:
array the array to check
message the exception message if the array has null elements
Throws:
java.lang.IllegalArgumentException if the array has null elements or is null
    public static void noNullElements(Object[] arrayString message) {
        Validate.notNull(array);
        for (int i = 0; i < array.lengthi++) {
            if (array[i] == null) {
                throw new IllegalArgumentException(message);
            }
        }
    }

    

Validate an argument, throwing IllegalArgumentException if the argument array has null elements or is null.

 Validate.noNullElements(myArray);
 

If the array has a null element the message in the exception is 'The validated array contains null element at index: '.

If the array is null then the message in the exception is 'The validated object is null'.

Parameters:
array the array to check
Throws:
java.lang.IllegalArgumentException if the array has null elements or is null
    public static void noNullElements(Object[] array) {
        Validate.notNull(array);
        for (int i = 0; i < array.lengthi++) {
            if (array[i] == null) {
                throw new IllegalArgumentException("The validated array contains null element at index: " + i);
            }
        }
    }
    // notNullElements collection
    //---------------------------------------------------------------------------------

    

Validate an argument, throwing IllegalArgumentException if the argument Collection has null elements or is null.

 Validate.noNullElements(myCollection, "The collection must not contain null elements");
 

If the collection is null then the message in the exception is 'The validated object is null'.

Parameters:
collection the collection to check
message the exception message if the collection has null elements
Throws:
java.lang.IllegalArgumentException if the collection has null elements or is null
    public static void noNullElements(Collection collectionString message) {
        Validate.notNull(collection);
        for (Iterator it = collection.iterator(); it.hasNext();) {
            if (it.next() == null) {
                throw new IllegalArgumentException(message);
            }
        }
    }

    

Validate an argument, throwing IllegalArgumentException if the argument Collection has null elements or is null.

 Validate.noNullElements(myCollection);
 

The message in the exception is 'The validated collection contains null element at index: '.

If the collection is null then the message in the exception is 'The validated object is null'.

Parameters:
collection the collection to check
Throws:
java.lang.IllegalArgumentException if the collection has null elements or is null
    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);
            }
        }
    }

    

Validate an argument, throwing IllegalArgumentException if the argument collection is null or has elements that are not of type clazz or a subclass.

 Validate.allElementsOfType(collection, String.class, "Collection has invalid elements");
 

Parameters:
collection the collection to check, not null
clazz the Class which the collection's elements are expected to be, not null
message the exception message if the Collection has elements not of type clazz
Since:
2.1
    public static void allElementsOfType(Collection collectionClass clazzString message) {
        Validate.notNull(collection);
        Validate.notNull(clazz);
        for (Iterator it = collection.iterator(); it.hasNext(); ) {
            if (clazz.isInstance(it.next()) == false) {
                throw new IllegalArgumentException(message);
            }
        }
    }

    

Validate an argument, throwing IllegalArgumentException if the argument collection is null or has elements that are not of type clazz or a subclass.

 Validate.allElementsOfType(collection, String.class);
 

The message in the exception is 'The validated collection contains an element not of type clazz at index: '.

Parameters:
collection the collection to check, not null
clazz the Class which the collection's elements are expected to be, not null
Since:
2.1
    public static void allElementsOfType(Collection collectionClass 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);
            }
        }
    }
New to GrepCode? Check out our FAQ X