/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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. * * JUniversal CHANGES: * The append method for StringBuffer was removed as StringBuffer isn't supported in JUniversal. */ package java.lang; /** * A modifiable {@link CharSequence sequence of characters} for use in creating and modifying * Strings. This class is intended as a direct replacement of {@link StringBuffer} for * non-concurrent use; unlike {@code StringBuffer} this class is not synchronized for thread safety. * <p> * The majority of the modification methods on this class return {@code StringBuilder}, so that, * like {@code StringBuffer}s, they can be used in chaining method calls together. For example, * {@code new StringBuilder("One * should ").append("always strive ").append("to achieve Harmony")}. * * JUniversal REMOVED: * * codePoint (aka surrogate) related methods, for Unicode characters > 65K, aren't currently * supported and were removed. * * serialization related methods * * append & insert methods for double and float * * * @see CharSequence * @see Appendable * @see StringBuffer * @see String * * @since 1.5 * */ public final class StringBuilder extends AbstractStringBuilder implements Appendable, CharSequence { /** * Constructs an instance with an initial capacity of {@code 16}. * * @see #capacity() */ public StringBuilder() { super(); } /** * Constructs an instance with the specified capacity. * * @param capacity * the initial capacity to use. * @throws NegativeArraySizeException * if the specified {@code capacity} is negative. * @see #capacity() */ public StringBuilder(int capacity) { super(capacity); } /** * Constructs an instance that's initialized with the contents of the * specified {@code CharSequence}. The capacity of the new builder will be * the length of the {@code CharSequence} plus 16. * * @param seq * the {@code CharSequence} to copy into the builder. * @throws NullPointerException * if {@code seq} is {@code null}. */ public StringBuilder(CharSequence seq) { super(seq.toString()); } /** * Constructs an instance that's initialized with the contents of the * specified {@code String}. The capacity of the new builder will be the * length of the {@code String} plus 16. * * @param str * the {@code String} to copy into the builder. * @throws NullPointerException * if {@code str} is {@code null}. */ public StringBuilder(String str) { super(str); } /** * Appends the string representation of the specified {@code boolean} value. * The {@code boolean} value is converted to a String according to the rule * defined by {@link String#valueOf(boolean)}. * * @param b * the {@code boolean} value to append. * @return this builder. * @see String#valueOf(boolean) */ public StringBuilder append(boolean b) { append0(b ? "true" : "false"); //$NON-NLS-1$ //$NON-NLS-2$ return this; } /** * Appends the string representation of the specified {@code char} value. * The {@code char} value is converted to a string according to the rule * defined by {@link String#valueOf(char)}. * * @param c * the {@code char} value to append. * @return this builder. * @see String#valueOf(char) */ public StringBuilder append(char c) { append0(c); return this; } /** * Appends the string representation of the specified {@code int} value. The * {@code int} value is converted to a string according to the rule defined * by {@link String#valueOf(int)}. * * @param i * the {@code int} value to append. * @return this builder. * @see String#valueOf(int) */ public StringBuilder append(int i) { append0(Integer.toString(i)); return this; } /** * Appends the string representation of the specified {@code long} value. * The {@code long} value is converted to a string according to the rule * defined by {@link String#valueOf(long)}. * * @param lng * the {@code long} value. * @return this builder. * @see String#valueOf(long) */ public StringBuilder append(long lng) { append0(Long.toString(lng)); return this; } /** * Appends the string representation of the specified {@code Object}. * The {@code Object} value is converted to a string according to the rule * defined by {@link String#valueOf(Object)}. * * @param obj * the {@code Object} to append. * @return this builder. * @see String#valueOf(Object) */ public StringBuilder append(Object obj) { if (obj == null) { appendNull(); } else { append0(obj.toString()); } return this; } /** * Appends the contents of the specified string. If the string is {@code * null}, then the string {@code "null"} is appended. * * @param str * the string to append. * @return this builder. */ public StringBuilder append(String str) { append0(str); return this; } /** * Appends the string representation of the specified {@code char[]}. * The {@code char[]} is converted to a string according to the rule * defined by {@link String#valueOf(char[])}. * * @param ch * the {@code char[]} to append.. * @return this builder. * @see String#valueOf(char[]) */ public StringBuilder append(char[] ch) { append0(ch); return this; } /** * Appends the string representation of the specified subset of the {@code * char[]}. The {@code char[]} value is converted to a String according to * the rule defined by {@link String#valueOf(char[],int,int)}. * * @param str * the {@code char[]} to append. * @param offset * the inclusive offset index. * @param len * the number of characters. * @return this builder. * @throws ArrayIndexOutOfBoundsException * if {@code offset} and {@code len} do not specify a valid * subsequence. * @see String#valueOf(char[],int,int) */ public StringBuilder append(char[] str, int offset, int len) { append0(str, offset, len); return this; } /** * Appends the string representation of the specified {@code CharSequence}. * If the {@code CharSequence} is {@code null}, then the string {@code * "null"} is appended. * * @param csq * the {@code CharSequence} to append. * @return this builder. */ public StringBuilder append(CharSequence csq) { if (csq == null) { appendNull(); } else { append0(csq.toString()); } return this; } /** * Appends the string representation of the specified subsequence of the * {@code CharSequence}. If the {@code CharSequence} is {@code null}, then * the string {@code "null"} is used to extract the subsequence from. * * @param csq * the {@code CharSequence} to append. * @param start * the beginning index. * @param end * the ending index. * @return this builder. * @throws IndexOutOfBoundsException * if {@code start} or {@code end} are negative, {@code start} * is greater than {@code end} or {@code end} is greater than * the length of {@code csq}. */ public StringBuilder append(CharSequence csq, int start, int end) { append0(csq, start, end); return this; } /** * Deletes a sequence of characters specified by {@code start} and {@code * end}. Shifts any remaining characters to the left. * * @param start * the inclusive start index. * @param end * the exclusive end index. * @return this builder. * @throws StringIndexOutOfBoundsException * if {@code start} is less than zero, greater than the current * length or greater than {@code end}. */ public StringBuilder delete(int start, int end) { delete0(start, end); return this; } /** * Deletes the character at the specified index. shifts any remaining * characters to the left. * * @param index * the index of the character to delete. * @return this builder. * @throws StringIndexOutOfBoundsException * if {@code index} is less than zero or is greater than or * equal to the current length. */ public StringBuilder deleteCharAt(int index) { deleteCharAt0(index); return this; } /** * Inserts the string representation of the specified {@code boolean} value * at the specified {@code offset}. The {@code boolean} value is converted * to a string according to the rule defined by * {@link String#valueOf(boolean)}. * * @param offset * the index to insert at. * @param b * the {@code boolean} value to insert. * @return this builder. * @throws StringIndexOutOfBoundsException * if {@code offset} is negative or greater than the current * {@code length}. * @see String#valueOf(boolean) */ public StringBuilder insert(int offset, boolean b) { insert0(offset, b ? "true" : "false"); //$NON-NLS-1$ //$NON-NLS-2$ return this; } /** * Inserts the string representation of the specified {@code char} value at * the specified {@code offset}. The {@code char} value is converted to a * string according to the rule defined by {@link String#valueOf(char)}. * * @param offset * the index to insert at. * @param c * the {@code char} value to insert. * @return this builder. * @throws IndexOutOfBoundsException * if {@code offset} is negative or greater than the current * {@code length()}. * @see String#valueOf(char) */ public StringBuilder insert(int offset, char c) { insert0(offset, c); return this; } /** * Inserts the string representation of the specified {@code int} value at * the specified {@code offset}. The {@code int} value is converted to a * String according to the rule defined by {@link String#valueOf(int)}. * * @param offset * the index to insert at. * @param i * the {@code int} value to insert. * @return this builder. * @throws StringIndexOutOfBoundsException * if {@code offset} is negative or greater than the current * {@code length()}. * @see String#valueOf(int) */ public StringBuilder insert(int offset, int i) { insert0(offset, Integer.toString(i)); return this; } /** * Inserts the string representation of the specified {@code long} value at * the specified {@code offset}. The {@code long} value is converted to a * String according to the rule defined by {@link String#valueOf(long)}. * * @param offset * the index to insert at. * @param l * the {@code long} value to insert. * @return this builder. * @throws StringIndexOutOfBoundsException * if {@code offset} is negative or greater than the current * {code length()}. * @see String#valueOf(long) */ public StringBuilder insert(int offset, long l) { insert0(offset, Long.toString(l)); return this; } /** * Inserts the string representation of the specified {@code Object} at the * specified {@code offset}. The {@code Object} value is converted to a * String according to the rule defined by {@link String#valueOf(Object)}. * * @param offset * the index to insert at. * @param obj * the {@code Object} to insert. * @return this builder. * @throws StringIndexOutOfBoundsException * if {@code offset} is negative or greater than the current * {@code length()}. * @see String#valueOf(Object) */ public StringBuilder insert(int offset, Object obj) { insert0(offset, obj == null ? "null" : obj.toString()); //$NON-NLS-1$ return this; } /** * Inserts the specified string at the specified {@code offset}. If the * specified string is null, then the String {@code "null"} is inserted. * * @param offset * the index to insert at. * @param str * the {@code String} to insert. * @return this builder. * @throws StringIndexOutOfBoundsException * if {@code offset} is negative or greater than the current * {@code length()}. */ public StringBuilder insert(int offset, String str) { insert0(offset, str); return this; } /** * Inserts the string representation of the specified {@code char[]} at the * specified {@code offset}. The {@code char[]} value is converted to a * String according to the rule defined by {@link String#valueOf(char[])}. * * @param offset * the index to insert at. * @param ch * the {@code char[]} to insert. * @return this builder. * @throws StringIndexOutOfBoundsException * if {@code offset} is negative or greater than the current * {@code length()}. * @see String#valueOf(char[]) */ public StringBuilder insert(int offset, char[] ch) { insert0(offset, ch); return this; } /** * Inserts the string representation of the specified subsequence of the * {@code char[]} at the specified {@code offset}. The {@code char[]} value * is converted to a String according to the rule defined by * {@link String#valueOf(char[],int,int)}. * * @param offset * the index to insert at. * @param str * the {@code char[]} to insert. * @param strOffset * the inclusive index. * @param strLen * the number of characters. * @return this builder. * @throws StringIndexOutOfBoundsException * if {@code offset} is negative or greater than the current * {@code length()}, or {@code strOffset} and {@code strLen} do * not specify a valid subsequence. * @see String#valueOf(char[],int,int) */ public StringBuilder insert(int offset, char[] str, int strOffset, int strLen) { insert0(offset, str, strOffset, strLen); return this; } /** * Inserts the string representation of the specified {@code CharSequence} * at the specified {@code offset}. The {@code CharSequence} is converted * to a String as defined by {@link CharSequence#toString()}. If {@code s} * is {@code null}, then the String {@code "null"} is inserted. * * @param offset * the index to insert at. * @param s * the {@code CharSequence} to insert. * @return this builder. * @throws IndexOutOfBoundsException * if {@code offset} is negative or greater than the current * {@code length()}. * @see CharSequence#toString() */ public StringBuilder insert(int offset, CharSequence s) { insert0(offset, s == null ? "null" : s.toString()); //$NON-NLS-1$ return this; } /** * Inserts the string representation of the specified subsequence of the * {@code CharSequence} at the specified {@code offset}. The {@code * CharSequence} is converted to a String as defined by * {@link CharSequence#subSequence(int, int)}. If the {@code CharSequence} * is {@code null}, then the string {@code "null"} is used to determine the * subsequence. * * @param offset * the index to insert at. * @param s * the {@code CharSequence} to insert. * @param start * the start of the subsequence of the character sequence. * @param end * the end of the subsequence of the character sequence. * @return this builder. * @throws IndexOutOfBoundsException * if {@code offset} is negative or greater than the current * {@code length()}, or {@code start} and {@code end} do not * specify a valid subsequence. * @see CharSequence#subSequence(int, int) */ public StringBuilder insert(int offset, CharSequence s, int start, int end) { insert0(offset, s, start, end); return this; } /** * Replaces the specified subsequence in this builder with the specified * string. * * @param start * the inclusive begin index. * @param end * the exclusive end index. * @param str * the replacement string. * @return this builder. * @throws StringIndexOutOfBoundsException * if {@code start} is negative, greater than the current * {@code length()} or greater than {@code end}. * @throws NullPointerException * if {@code str} is {@code null}. */ public StringBuilder replace(int start, int end, String str) { replace0(start, end, str); return this; } /** * Reverses the order of characters in this builder. * * @return this buffer. */ public StringBuilder reverse() { reverse0(); return this; } /** * Returns the contents of this builder. * * @return the string representation of the data in this builder. */ @Override public String toString() { /* Note: This method is required to workaround a compiler bug * in the RI javac (at least in 1.5.0_06) that will generate a * reference to the non-public AbstractStringBuilder if we don't * override it here. */ return super.toString(); } }