/*
* Copyright 2002-2007 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.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</code> 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 Log logger = LogFactory.getLog(ValidationUtils.class);
/**
* Invoke the given {@link Validator} for the supplied object and
* {@link Errors} instance.
* @param validator the <code>Validator</code> to be invoked (must not be <code>null</code>)
* @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</code>)
* @throws IllegalArgumentException if either of the <code>Validator</code> or <code>Errors</code> arguments is <code>null</code>;
* or if the supplied <code>Validator</code> 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) {
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() + "]");
}
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</code> 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</code> 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</code> 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</code> 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 codea nd error arguments
* if the value is empty.
* <p>An 'empty' value in this context means either <code>null</code> 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</code> 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</code>)
*/
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</code> 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</code> 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</code>)
* @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</code>,
* 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</code> 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</code>,
* 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</code> 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</code>,
* 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</code> 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</code>)
*/
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</code>,
* 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</code> 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</code>)
* @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);
}
}
}