/*
* Copyright 2002-2014 the original author or authors.
*
* Licensed 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.springframework.validation;
import org.apache.commons.logging.
Log;
import org.apache.commons.logging.
LogFactory;
import org.springframework.util.
Assert;
import org.springframework.util.
ObjectUtils;
import org.springframework.util.
StringUtils;
/**
* Utility class offering convenient methods for invoking a {@link Validator}
* and for rejecting empty fields.
*
* <p>Checks for an empty field in {@code Validator} implementations can become
* one-liners when using {@link #rejectIfEmpty} or {@link #rejectIfEmptyOrWhitespace}.
*
* @author Juergen Hoeller
* @author Dmitriy Kopylenko
* @since 06.05.2003
* @see Validator
* @see Errors
*/
public abstract class
ValidationUtils {
private static final
Log logger =
LogFactory.
getLog(
ValidationUtils.class);
/**
* Invoke the given {@link Validator} for the supplied object and
* {@link Errors} instance.
* @param validator the {@code Validator} to be invoked (must not be {@code null})
* @param obj the object to bind the parameters to
* @param errors the {@link Errors} instance that should store the errors (must not be {@code null})
* @throws IllegalArgumentException if either of the {@code Validator} or {@code Errors} arguments is
* {@code null}, or if the supplied {@code Validator} does not {@link Validator#supports(Class) support}
* the validation of the supplied object's type
*/
public static void
invokeValidator(
Validator validator,
Object obj,
Errors errors) {
invokeValidator(
validator,
obj,
errors, (
Object[]) null);
}
/**
* Invoke the given {@link Validator}/{@link SmartValidator} for the supplied object and
* {@link Errors} instance.
* @param validator the {@code Validator} to be invoked (must not be {@code null})
* @param obj the object to bind the parameters to
* @param errors the {@link Errors} instance that should store the errors (must not be {@code null})
* @param validationHints one or more hint objects to be passed to the validation engine
* @throws IllegalArgumentException if either of the {@code Validator} or {@code Errors} arguments is
* {@code null}, or if the supplied {@code Validator} does not {@link Validator#supports(Class) support}
* the validation of the supplied object's type
*/
public static void
invokeValidator(
Validator validator,
Object obj,
Errors errors,
Object...
validationHints) {
Assert.
notNull(
validator, "Validator must not be null");
Assert.
notNull(
errors, "Errors object must not be null");
if (
logger.
isDebugEnabled()) {
logger.
debug("Invoking validator [" +
validator + "]");
}
if (
obj != null && !
validator.
supports(
obj.
getClass())) {
throw new
IllegalArgumentException(
"Validator [" +
validator.
getClass() + "] does not support [" +
obj.
getClass() + "]");
}
if (!
ObjectUtils.
isEmpty(
validationHints) &&
validator instanceof
SmartValidator) {
((
SmartValidator)
validator).
validate(
obj,
errors,
validationHints);
}
else {
validator.
validate(
obj,
errors);
}
if (
logger.
isDebugEnabled()) {
if (
errors.
hasErrors()) {
logger.
debug("Validator found " +
errors.
getErrorCount() + " errors");
}
else {
logger.
debug("Validator found no errors");
}
}
}
/**
* Reject the given field with the given error code if the value is empty.
* <p>An 'empty' value in this context means either {@code null} or
* the empty string "".
* <p>The object whose field is being validated does not need to be passed
* in because the {@link Errors} instance can resolve field values by itself
* (it will usually hold an internal reference to the target object).
* @param errors the {@code Errors} instance to register errors on
* @param field the field name to check
* @param errorCode the error code, interpretable as message key
*/
public static void
rejectIfEmpty(
Errors errors,
String field,
String errorCode) {
rejectIfEmpty(
errors,
field,
errorCode, null, null);
}
/**
* Reject the given field with the given error code and default message
* if the value is empty.
* <p>An 'empty' value in this context means either {@code null} or
* the empty string "".
* <p>The object whose field is being validated does not need to be passed
* in because the {@link Errors} instance can resolve field values by itself
* (it will usually hold an internal reference to the target object).
* @param errors the {@code Errors} instance to register errors on
* @param field the field name to check
* @param errorCode error code, interpretable as message key
* @param defaultMessage fallback default message
*/
public static void
rejectIfEmpty(
Errors errors,
String field,
String errorCode,
String defaultMessage) {
rejectIfEmpty(
errors,
field,
errorCode, null,
defaultMessage);
}
/**
* Reject the given field with the given error code and error arguments
* if the value is empty.
* <p>An 'empty' value in this context means either {@code null} or
* the empty string "".
* <p>The object whose field is being validated does not need to be passed
* in because the {@link Errors} instance can resolve field values by itself
* (it will usually hold an internal reference to the target object).
* @param errors the {@code Errors} instance to register errors on
* @param field the field name to check
* @param errorCode the error code, interpretable as message key
* @param errorArgs the error arguments, for argument binding via MessageFormat
* (can be {@code null})
*/
public static void
rejectIfEmpty(
Errors errors,
String field,
String errorCode,
Object[]
errorArgs) {
rejectIfEmpty(
errors,
field,
errorCode,
errorArgs, null);
}
/**
* Reject the given field with the given error code, error arguments
* and default message if the value is empty.
* <p>An 'empty' value in this context means either {@code null} or
* the empty string "".
* <p>The object whose field is being validated does not need to be passed
* in because the {@link Errors} instance can resolve field values by itself
* (it will usually hold an internal reference to the target object).
* @param errors the {@code Errors} instance to register errors on
* @param field the field name to check
* @param errorCode the error code, interpretable as message key
* @param errorArgs the error arguments, for argument binding via MessageFormat
* (can be {@code null})
* @param defaultMessage fallback default message
*/
public static void
rejectIfEmpty(
Errors errors,
String field,
String errorCode,
Object[]
errorArgs,
String defaultMessage) {
Assert.
notNull(
errors, "Errors object must not be null");
Object value =
errors.
getFieldValue(
field);
if (
value == null || !
StringUtils.
hasLength(
value.
toString())) {
errors.
rejectValue(
field,
errorCode,
errorArgs,
defaultMessage);
}
}
/**
* Reject the given field with the given error code if the value is empty
* or just contains whitespace.
* <p>An 'empty' value in this context means either {@code null},
* the empty string "", or consisting wholly of whitespace.
* <p>The object whose field is being validated does not need to be passed
* in because the {@link Errors} instance can resolve field values by itself
* (it will usually hold an internal reference to the target object).
* @param errors the {@code Errors} instance to register errors on
* @param field the field name to check
* @param errorCode the error code, interpretable as message key
*/
public static void
rejectIfEmptyOrWhitespace(
Errors errors,
String field,
String errorCode) {
rejectIfEmptyOrWhitespace(
errors,
field,
errorCode, null, null);
}
/**
* Reject the given field with the given error code and default message
* if the value is empty or just contains whitespace.
* <p>An 'empty' value in this context means either {@code null},
* the empty string "", or consisting wholly of whitespace.
* <p>The object whose field is being validated does not need to be passed
* in because the {@link Errors} instance can resolve field values by itself
* (it will usually hold an internal reference to the target object).
* @param errors the {@code Errors} instance to register errors on
* @param field the field name to check
* @param errorCode the error code, interpretable as message key
* @param defaultMessage fallback default message
*/
public static void
rejectIfEmptyOrWhitespace(
Errors errors,
String field,
String errorCode,
String defaultMessage) {
rejectIfEmptyOrWhitespace(
errors,
field,
errorCode, null,
defaultMessage);
}
/**
* Reject the given field with the given error code and error arguments
* if the value is empty or just contains whitespace.
* <p>An 'empty' value in this context means either {@code null},
* the empty string "", or consisting wholly of whitespace.
* <p>The object whose field is being validated does not need to be passed
* in because the {@link Errors} instance can resolve field values by itself
* (it will usually hold an internal reference to the target object).
* @param errors the {@code Errors} instance to register errors on
* @param field the field name to check
* @param errorCode the error code, interpretable as message key
* @param errorArgs the error arguments, for argument binding via MessageFormat
* (can be {@code null})
*/
public static void
rejectIfEmptyOrWhitespace(
Errors errors,
String field,
String errorCode,
Object[]
errorArgs) {
rejectIfEmptyOrWhitespace(
errors,
field,
errorCode,
errorArgs, null);
}
/**
* Reject the given field with the given error code, error arguments
* and default message if the value is empty or just contains whitespace.
* <p>An 'empty' value in this context means either {@code null},
* the empty string "", or consisting wholly of whitespace.
* <p>The object whose field is being validated does not need to be passed
* in because the {@link Errors} instance can resolve field values by itself
* (it will usually hold an internal reference to the target object).
* @param errors the {@code Errors} instance to register errors on
* @param field the field name to check
* @param errorCode the error code, interpretable as message key
* @param errorArgs the error arguments, for argument binding via MessageFormat
* (can be {@code null})
* @param defaultMessage fallback default message
*/
public static void
rejectIfEmptyOrWhitespace(
Errors errors,
String field,
String errorCode,
Object[]
errorArgs,
String defaultMessage) {
Assert.
notNull(
errors, "Errors object must not be null");
Object value =
errors.
getFieldValue(
field);
if (
value == null ||!
StringUtils.
hasText(
value.
toString())) {
errors.
rejectValue(
field,
errorCode,
errorArgs,
defaultMessage);
}
}
}