001package ezvcard.util;
002
003/*
004 Copyright (c) 2012-2023, Michael Angstadt
005 All rights reserved.
006
007 Redistribution and use in source and binary forms, with or without
008 modification, are permitted provided that the following conditions are met: 
009
010 1. Redistributions of source code must retain the above copyright notice, this
011 list of conditions and the following disclaimer. 
012 2. Redistributions in binary form must reproduce the above copyright notice,
013 this list of conditions and the following disclaimer in the documentation
014 and/or other materials provided with the distribution. 
015
016 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
017 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
018 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
019 DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
020 ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
021 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
022 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
023 ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
024 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
025 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
026
027 The views and conclusions contained in the software and documentation are those
028 of the authors and should not be interpreted as representing official policies, 
029 either expressed or implied, of the FreeBSD Project.
030 */
031
032/**
033 * Wraps a {@link StringBuilder} object, providing utility methods for clearing
034 * it.
035 */
036public class ClearableStringBuilder {
037        private final StringBuilder sb = new StringBuilder();
038
039        /**
040         * Clears the buffer.
041         * @return this
042         */
043        public ClearableStringBuilder clear() {
044                sb.setLength(0);
045                return this;
046        }
047
048        /**
049         * Gets the buffer's contents.
050         * @return the buffer's contents
051         */
052        public String get() {
053                return sb.toString();
054        }
055
056        /**
057         * Gets the buffer's contents, then clears it.
058         * @return the buffer's contents
059         */
060        public String getAndClear() {
061                String string = get();
062                clear();
063                return string;
064        }
065
066        /**
067         * Appends a character to the buffer.
068         * @param ch the character to append
069         * @return this
070         */
071        public ClearableStringBuilder append(char ch) {
072                sb.append(ch);
073                return this;
074        }
075
076        /**
077         * Appends a character sequence to the buffer.
078         * @param string the character sequence to append
079         * @return this
080         */
081        public ClearableStringBuilder append(CharSequence string) {
082                sb.append(string);
083                return this;
084        }
085
086        /**
087         * Appends a character array to the buffer.
088         * @param buffer the characters to append
089         * @param start the index of the first char to append
090         * @param length the number of chars to append
091         * @return this
092         */
093        public ClearableStringBuilder append(char[] buffer, int start, int length) {
094                sb.append(buffer, start, length);
095                return this;
096        }
097
098        /**
099         * Removes the last character from the buffer.
100         * @return this
101         */
102        public ClearableStringBuilder chop() {
103                sb.setLength(sb.length() - 1);
104                return this;
105        }
106
107        /**
108         * Gets the length of the buffer.
109         * @return the buffer's length
110         */
111        public int length() {
112                return sb.length();
113        }
114}