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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 java.beans.PropertyEditor; import java.io.Serializable; import java.util.Collections; import java.util.HashMap; import java.util.HashSet; import java.util.LinkedHashMap; import java.util.LinkedList; import java.util.List; import java.util.Map; import java.util.Set; import org.springframework.beans.PropertyEditorRegistry; import org.springframework.lang.Nullable; import org.springframework.util.Assert; import org.springframework.util.ObjectUtils; import org.springframework.util.StringUtils; /** * Abstract implementation of the {@link BindingResult} interface and * its super-interface {@link Errors}. Encapsulates common management of * {@link ObjectError ObjectErrors} and {@link FieldError FieldErrors}. * * @author Juergen Hoeller * @author Rob Harrop * @since 2.0 * @see Errors */ @SuppressWarnings("serial") public abstract class AbstractBindingResult extends AbstractErrors implements BindingResult, Serializable { private final String objectName; private MessageCodesResolver messageCodesResolver = new DefaultMessageCodesResolver(); private final List<ObjectError> errors = new LinkedList<>(); private final Map<String, Class<?>> fieldTypes = new HashMap<>(); private final Map<String, Object> fieldValues = new HashMap<>(); private final Set<String> suppressedFields = new HashSet<>(); /** * Create a new AbstractBindingResult instance. * @param objectName the name of the target object * @see DefaultMessageCodesResolver */ protected AbstractBindingResult(String objectName) { this.objectName = objectName; } /** * Set the strategy to use for resolving errors into message codes. * Default is DefaultMessageCodesResolver. * @see DefaultMessageCodesResolver */ public void setMessageCodesResolver(MessageCodesResolver messageCodesResolver) { Assert.notNull(messageCodesResolver, "MessageCodesResolver must not be null"); this.messageCodesResolver = messageCodesResolver; } /** * Return the strategy to use for resolving errors into message codes. */ public MessageCodesResolver getMessageCodesResolver() { return this.messageCodesResolver; } //--------------------------------------------------------------------- // Implementation of the Errors interface //--------------------------------------------------------------------- @Override public String getObjectName() { return this.objectName; } @Override public void reject(String errorCode, @Nullable Object[] errorArgs, @Nullable String defaultMessage) { addError(new ObjectError(getObjectName(), resolveMessageCodes(errorCode), errorArgs, defaultMessage)); } @Override public void rejectValue(@Nullable String field, String errorCode, @Nullable Object[] errorArgs, @Nullable String defaultMessage) { if ("".equals(getNestedPath()) && !StringUtils.hasLength(field)) { // We're at the top of the nested object hierarchy, // so the present level is not a field but rather the top object. // The best we can do is register a global error here... reject(errorCode, errorArgs, defaultMessage); return; } String fixedField = fixedField(field); Object newVal = getActualFieldValue(fixedField); FieldError fe = new FieldError(getObjectName(), fixedField, newVal, false, resolveMessageCodes(errorCode, field), errorArgs, defaultMessage); addError(fe); } @Override public void addAllErrors(Errors errors) { if (!errors.getObjectName().equals(getObjectName())) { throw new IllegalArgumentException("Errors object needs to have same object name"); } this.errors.addAll(errors.getAllErrors()); } @Override public boolean hasErrors() { return !this.errors.isEmpty(); } @Override public int getErrorCount() { return this.errors.size(); } @Override public List<ObjectError> getAllErrors() { return Collections.unmodifiableList(this.errors); } @Override public List<ObjectError> getGlobalErrors() { List<ObjectError> result = new LinkedList<>(); for (ObjectError objectError : this.errors) { if (!(objectError instanceof FieldError)) { result.add(objectError); } } return Collections.unmodifiableList(result); } @Override @Nullable public ObjectError getGlobalError() { for (ObjectError objectError : this.errors) { if (!(objectError instanceof FieldError)) { return objectError; } } return null; } @Override public List<FieldError> getFieldErrors() { List<FieldError> result = new LinkedList<>(); for (ObjectError objectError : this.errors) { if (objectError instanceof FieldError) { result.add((FieldError) objectError); } } return Collections.unmodifiableList(result); } @Override @Nullable public FieldError getFieldError() { for (ObjectError objectError : this.errors) { if (objectError instanceof FieldError) { return (FieldError) objectError; } } return null; } @Override public List<FieldError> getFieldErrors(String field) { List<FieldError> result = new LinkedList<>(); String fixedField = fixedField(field); for (ObjectError objectError : this.errors) { if (objectError instanceof FieldError && isMatchingFieldError(fixedField, (FieldError) objectError)) { result.add((FieldError) objectError); } } return Collections.unmodifiableList(result); } @Override @Nullable public FieldError getFieldError(String field) { String fixedField = fixedField(field); for (ObjectError objectError : this.errors) { if (objectError instanceof FieldError) { FieldError fieldError = (FieldError) objectError; if (isMatchingFieldError(fixedField, fieldError)) { return fieldError; } } } return null; } @Override @Nullable public Object getFieldValue(String field) { FieldError fieldError = getFieldError(field); // Use rejected value in case of error, current field value otherwise. if (fieldError != null) { Object value = fieldError.getRejectedValue(); // Do not apply formatting on binding failures like type mismatches. return (fieldError.isBindingFailure() || getTarget() == null ? value : formatFieldValue(field, value)); } else if (getTarget() != null) { Object value = getActualFieldValue(fixedField(field)); return formatFieldValue(field, value); } else { return this.fieldValues.get(field); } } /** * This default implementation determines the type based on the actual * field value, if any. Subclasses should override this to determine * the type from a descriptor, even for {@code null} values. * @see #getActualFieldValue */ @Override @Nullable public Class<?> getFieldType(@Nullable String field) { if (getTarget() != null) { Object value = getActualFieldValue(fixedField(field)); if (value != null) { return value.getClass(); } } return this.fieldTypes.get(field); } //--------------------------------------------------------------------- // Implementation of BindingResult interface //--------------------------------------------------------------------- /** * Return a model Map for the obtained state, exposing an Errors * instance as '{@link #MODEL_KEY_PREFIX MODEL_KEY_PREFIX} + objectName' * and the object itself. * <p>Note that the Map is constructed every time you're calling this method. * Adding things to the map and then re-calling this method will not work. * <p>The attributes in the model Map returned by this method are usually * included in the ModelAndView for a form view that uses Spring's bind tag, * which needs access to the Errors instance. * @see #getObjectName * @see #MODEL_KEY_PREFIX */ @Override public Map<String, Object> getModel() { Map<String, Object> model = new LinkedHashMap<>(2); // Mapping from name to target object. model.put(getObjectName(), getTarget()); // Errors instance, even if no errors. model.put(MODEL_KEY_PREFIX + getObjectName(), this); return model; } @Override @Nullable public Object getRawFieldValue(String field) { return (getTarget() != null ? getActualFieldValue(fixedField(field)) : null); } /** * This implementation delegates to the * {@link #getPropertyEditorRegistry() PropertyEditorRegistry}'s * editor lookup facility, if available. */ @Override @Nullable public PropertyEditor findEditor(@Nullable String field, @Nullable Class<?> valueType) { PropertyEditorRegistry editorRegistry = getPropertyEditorRegistry(); if (editorRegistry != null) { Class<?> valueTypeToUse = valueType; if (valueTypeToUse == null) { valueTypeToUse = getFieldType(field); } return editorRegistry.findCustomEditor(valueTypeToUse, fixedField(field)); } else { return null; } } /** * This implementation returns {@code null}. */ @Override @Nullable public PropertyEditorRegistry getPropertyEditorRegistry() { return null; } @Override public String[] resolveMessageCodes(String errorCode) { return getMessageCodesResolver().resolveMessageCodes(errorCode, getObjectName()); } @Override public String[] resolveMessageCodes(String errorCode, @Nullable String field) { return getMessageCodesResolver().resolveMessageCodes(errorCode, getObjectName(), fixedField(field), getFieldType(field)); } @Override public void addError(ObjectError error) { this.errors.add(error); } @Override public void recordFieldValue(String field, Class<?> type, @Nullable Object value) { this.fieldTypes.put(field, type); this.fieldValues.put(field, value); } /** * Mark the specified disallowed field as suppressed. * <p>The data binder invokes this for each field value that was * detected to target a disallowed field. * @see DataBinder#setAllowedFields */ @Override public void recordSuppressedField(String field) { this.suppressedFields.add(field); } /** * Return the list of fields that were suppressed during the bind process. * <p>Can be used to determine whether any field values were targeting * disallowed fields. * @see DataBinder#setAllowedFields */ @Override public String[] getSuppressedFields() { return StringUtils.toStringArray(this.suppressedFields); } @Override public boolean equals(@Nullable Object other) { if (this == other) { return true; } if (!(other instanceof BindingResult)) { return false; } BindingResult otherResult = (BindingResult) other; return (getObjectName().equals(otherResult.getObjectName()) && ObjectUtils.nullSafeEquals(getTarget(), otherResult.getTarget()) && getAllErrors().equals(otherResult.getAllErrors())); } @Override public int hashCode() { return getObjectName().hashCode(); } //--------------------------------------------------------------------- // Template methods to be implemented/overridden by subclasses //--------------------------------------------------------------------- /** * Return the wrapped target object. */ @Override @Nullable public abstract Object getTarget(); /** * Extract the actual field value for the given field. * @param field the field to check * @return the current value of the field */ @Nullable protected abstract Object getActualFieldValue(String field); /** * Format the given value for the specified field. * <p>The default implementation simply returns the field value as-is. * @param field the field to check * @param value the value of the field (either a rejected value * other than from a binding error, or an actual field value) * @return the formatted value */ @Nullable protected Object formatFieldValue(String field, @Nullable Object value) { return value; } }