001/*
002 * Copyright 2002-2017 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.core.style;
018
019import org.springframework.lang.Nullable;
020
021/**
022 * A strategy interface for pretty-printing {@code toString()} methods.
023 * Encapsulates the print algorithms; some other object such as a builder
024 * should provide the workflow.
025 *
026 * @author Keith Donald
027 * @since 1.2.2
028 */
029public interface ToStringStyler {
030
031        /**
032         * Style a {@code toString()}'ed object before its fields are styled.
033         * @param buffer the buffer to print to
034         * @param obj the object to style
035         */
036        void styleStart(StringBuilder buffer, Object obj);
037
038        /**
039         * Style a {@code toString()}'ed object after it's fields are styled.
040         * @param buffer the buffer to print to
041         * @param obj the object to style
042         */
043        void styleEnd(StringBuilder buffer, Object obj);
044
045        /**
046         * Style a field value as a string.
047         * @param buffer the buffer to print to
048         * @param fieldName the he name of the field
049         * @param value the field value
050         */
051        void styleField(StringBuilder buffer, String fieldName, @Nullable Object value);
052
053        /**
054         * Style the given value.
055         * @param buffer the buffer to print to
056         * @param value the field value
057         */
058        void styleValue(StringBuilder buffer, Object value);
059
060        /**
061         * Style the field separator.
062         * @param buffer the buffer to print to
063         */
064        void styleFieldSeparator(StringBuilder buffer);
065
066}