/*
 * 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
 *
 *      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.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.ObjectUtils;

/**
 * Encapsulates a field error, that is, a reason for rejecting a specific
 * field value.
 *
 * <p>See the {@link DefaultMessageCodesResolver} javadoc for details on
 * how a message code list is built for a {@code FieldError}.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @since 10.03.2003
 * @see DefaultMessageCodesResolver
 */
@SuppressWarnings("serial")
public class FieldError extends ObjectError {

	private final String field;

	@Nullable
	private final Object rejectedValue;

	private final boolean bindingFailure;


	/**
	 * Create a new FieldError instance.
	 * @param objectName the name of the affected object
	 * @param field the affected field of the object
	 * @param defaultMessage the default message to be used to resolve this message
	 */
	public FieldError(String objectName, String field, String defaultMessage) {
		this(objectName, field, null, false, null, null, defaultMessage);
	}

	/**
	 * Create a new FieldError instance.
	 * @param objectName the name of the affected object
	 * @param field the affected field of the object
	 * @param rejectedValue the rejected field value
	 * @param bindingFailure whether this error represents a binding failure
	 * (like a type mismatch); else, it is a validation failure
	 * @param codes the codes to be used to resolve this message
	 * @param arguments the array of arguments to be used to resolve this message
	 * @param defaultMessage the default message to be used to resolve this message
	 */
	public FieldError(String objectName, String field, @Nullable Object rejectedValue, boolean bindingFailure,
			@Nullable String[] codes, @Nullable Object[] arguments, @Nullable String defaultMessage) {

		super(objectName, codes, arguments, defaultMessage);
		Assert.notNull(field, "Field must not be null");
		this.field = field;
		this.rejectedValue = rejectedValue;
		this.bindingFailure = bindingFailure;
	}


	/**
	 * Return the affected field of the object.
	 */
	public String getField() {
		return this.field;
	}

	/**
	 * Return the rejected field value.
	 */
	@Nullable
	public Object getRejectedValue() {
		return this.rejectedValue;
	}

	/**
	 * Return whether this error represents a binding failure
	 * (like a type mismatch); otherwise it is a validation failure.
	 */
	public boolean isBindingFailure() {
		return this.bindingFailure;
	}


	@Override
	public boolean equals(@Nullable Object other) {
		if (this == other) {
			return true;
		}
		if (!super.equals(other)) {
			return false;
		}
		FieldError otherError = (FieldError) other;
		return (getField().equals(otherError.getField()) &&
				ObjectUtils.nullSafeEquals(getRejectedValue(), otherError.getRejectedValue()) &&
				isBindingFailure() == otherError.isBindingFailure());
	}

	@Override
	public int hashCode() {
		int hashCode = super.hashCode();
		hashCode = 29 * hashCode + getField().hashCode();
		hashCode = 29 * hashCode + ObjectUtils.nullSafeHashCode(getRejectedValue());
		hashCode = 29 * hashCode + (isBindingFailure() ? 1 : 0);
		return hashCode;
	}

	@Override
	public String toString() {
		return "Field error in object '" + getObjectName() + "' on field '" + this.field +
				"': rejected value [" + ObjectUtils.nullSafeToString(this.rejectedValue) + "]; " +
				resolvableToString();
	}

}
