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/* * Copyright 2002-2018 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 * * https://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.springframework.beans.PropertyAccessException; import org.springframework.context.support.DefaultMessageSourceResolvable; import org.springframework.util.Assert; import org.springframework.util.ObjectUtils; import org.springframework.util.StringUtils; /** * Default {@link BindingErrorProcessor} implementation. * * <p>Uses the "required" error code and the field name to resolve message codes * for a missing field error. * * <p>Creates a {@code FieldError} for each {@code PropertyAccessException} * given, using the {@code PropertyAccessException}'s error code ("typeMismatch", * "methodInvocation") for resolving message codes. * * @author Alef Arendsen * @author Juergen Hoeller * @since 1.2 * @see #MISSING_FIELD_ERROR_CODE * @see DataBinder#setBindingErrorProcessor * @see BeanPropertyBindingResult#addError * @see BeanPropertyBindingResult#resolveMessageCodes * @see org.springframework.beans.PropertyAccessException#getErrorCode * @see org.springframework.beans.TypeMismatchException#ERROR_CODE * @see org.springframework.beans.MethodInvocationException#ERROR_CODE */ public class DefaultBindingErrorProcessor implements BindingErrorProcessor { /** * Error code that a missing field error (i.e. a required field not * found in the list of property values) will be registered with: * "required". */ public static final String MISSING_FIELD_ERROR_CODE = "required"; @Override public void processMissingFieldError(String missingField, BindingResult bindingResult) { // Create field error with code "required". String fixedField = bindingResult.getNestedPath() + missingField; String[] codes = bindingResult.resolveMessageCodes(MISSING_FIELD_ERROR_CODE, missingField); Object[] arguments = getArgumentsForBindError(bindingResult.getObjectName(), fixedField); FieldError error = new FieldError(bindingResult.getObjectName(), fixedField, "", true, codes, arguments, "Field '" + fixedField + "' is required"); bindingResult.addError(error); } @Override public void processPropertyAccessException(PropertyAccessException ex, BindingResult bindingResult) { // Create field error with the exceptions's code, e.g. "typeMismatch". String field = ex.getPropertyName(); Assert.state(field != null, "No field in exception"); String[] codes = bindingResult.resolveMessageCodes(ex.getErrorCode(), field); Object[] arguments = getArgumentsForBindError(bindingResult.getObjectName(), field); Object rejectedValue = ex.getValue(); if (ObjectUtils.isArray(rejectedValue)) { rejectedValue = StringUtils.arrayToCommaDelimitedString(ObjectUtils.toObjectArray(rejectedValue)); } FieldError error = new FieldError(bindingResult.getObjectName(), field, rejectedValue, true, codes, arguments, ex.getLocalizedMessage()); error.wrap(ex); bindingResult.addError(error); } /** * Return FieldError arguments for a binding error on the given field. * Invoked for each missing required field and each type mismatch. * <p>The default implementation returns a single argument indicating the field name * (of type DefaultMessageSourceResolvable, with "objectName.field" and "field" as codes). * @param objectName the name of the target object * @param field the field that caused the binding error * @return the Object array that represents the FieldError arguments * @see org.springframework.validation.FieldError#getArguments * @see org.springframework.context.support.DefaultMessageSourceResolvable */ protected Object[] getArgumentsForBindError(String objectName, String field) { String[] codes = new String[] { objectName + Errors.NESTED_PATH_SEPARATOR + field, field }; return new Object[] { new DefaultMessageSourceResolvable(codes, field) }; } }