/* * 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. */ package java.lang; /** * A modifiable {@link CharSequence sequence of characters} for use in creating and modifying * Strings. This class is intended as a base class for {@link StringBuffer} and * {@link StringBuilder}. * * JUniversal REMOVED: * * codePoint (aka surrogate) related methods, for Unicode characters > 65K, aren't currently * supported and were removed. * * serialization related methods * * * @see StringBuffer * @see StringBuilder * @since 1.5 */ abstract class AbstractStringBuilder { static final int INITIAL_CAPACITY = 16; private char[] value; private int count; private boolean shared; /* * Returns the character array. */ final char[] getValue() { return value; } /* * Returns the underlying buffer and sets the shared flag. */ final char[] shareValue() { shared = true; return value; } AbstractStringBuilder() { value = new char[INITIAL_CAPACITY]; } AbstractStringBuilder(int capacity) { if (capacity < 0) { throw new java.lang.NegativeArraySizeException(); } value = new char[capacity]; } AbstractStringBuilder(String string) { count = string.length(); shared = false; value = new char[count + INITIAL_CAPACITY]; string.getChars(0, count, value, 0); } private void enlargeBuffer(int min) { int newSize = ((value.length >> 1) + value.length) + 2; char[] newData = new char[min > newSize ? min : newSize]; JUniversalHelper.arraycopy(value, newData, count); value = newData; shared = false; } final void appendNull() { int newSize = count + 4; if (newSize > value.length) { enlargeBuffer(newSize); } value[count++] = 'n'; value[count++] = 'u'; value[count++] = 'l'; value[count++] = 'l'; } final void append0(char[] chars) { int newSize = count + chars.length; if (newSize > value.length) { enlargeBuffer(newSize); } JUniversalHelper.arraycopy(chars, 0, value, count, chars.length); count = newSize; } final void append0(char[] chars, int offset, int length) { // Force null check of chars first! if (offset > chars.length || offset < 0) { // luni.12=Offset out of bounds \: {0} throw new java.lang.ArrayIndexOutOfBoundsException(new StringBuilder( "Offset out of bounds : ").append(offset).toString()); } if (length < 0 || chars.length - offset < length) { // luni.18=Length out of bounds \: {0} throw new java.lang.ArrayIndexOutOfBoundsException( new StringBuilder("Length out of bounds : ").append(length).toString()); } int newSize = count + length; if (newSize > value.length) { enlargeBuffer(newSize); } JUniversalHelper.arraycopy(chars, offset, value, count, length); count = newSize; } final void append0(char ch) { if (count == value.length) { enlargeBuffer(count + 1); } value[count++] = ch; } final void append0(String string) { if (string == null) { appendNull(); return; } int adding = string.length(); int newSize = count + adding; if (newSize > value.length) { enlargeBuffer(newSize); } string.getChars(0, adding, value, count); count = newSize; } final void append0(CharSequence s, int start, int end) { if (s == null) { s = "null"; //$NON-NLS-1$ } if (start < 0 || end < 0 || start > end || end > s.length()) { throw new java.lang.IndexOutOfBoundsException(); } append0(s.subSequence(start, end).toString()); } /** * Returns the number of characters that can be held without growing. * * @return the capacity * @see #ensureCapacity * @see #length */ public int capacity() { return value.length; } /** * Retrieves the character at the {@code index}. * * @param index * the index of the character to retrieve. * @return the char value. * @throws IndexOutOfBoundsException * if {@code index} is negative or greater than or equal to the * current {@link #length()}. */ public char charAt(int index) { if (index < 0 || index >= count) { throw new java.lang.StringIndexOutOfBoundsException(index); } return value[index]; } final void delete0(int start, int end) { if (start >= 0) { if (end > count) { end = count; } if (end == start) { return; } if (end > start) { int length = count - end; if (length >= 0) { if (!shared) { JUniversalHelper.arraycopy(value, end, value, start, length); } else { char[] newData = new char[value.length]; JUniversalHelper.arraycopy(value, 0, newData, 0, start); JUniversalHelper.arraycopy(value, end, newData, start, length); value = newData; shared = false; } } count -= end - start; return; } } throw new java.lang.StringIndexOutOfBoundsException(); } final void deleteCharAt0(int location) { if (0 > location || location >= count) { throw new java.lang.StringIndexOutOfBoundsException(location); } int length = count - location - 1; if (length > 0) { if (!shared) { JUniversalHelper.arraycopy(value, location + 1, value, location, length); } else { char[] newData = new char[value.length]; JUniversalHelper.arraycopy(value, newData, location); JUniversalHelper.arraycopy(value, location + 1, newData, location, length); value = newData; shared = false; } } count--; } /** * Ensures that this object has a minimum capacity available before * requiring the internal buffer to be enlarged. The general policy of this * method is that if the {@code minimumCapacity} is larger than the current * {@link #capacity()}, then the capacity will be increased to the largest * value of either the {@code minimumCapacity} or the current capacity * multiplied by two plus two. Although this is the general policy, there is * no guarantee that the capacity will change. * * @param min * the new minimum capacity to set. */ public void ensureCapacity(int min) { if (min > value.length) { int twice = (value.length << 1) + 2; enlargeBuffer(twice > min ? twice : min); } } /** * Copies the requested sequence of characters to the {@code char[]} passed * starting at {@code destStart}. * * @param start * the inclusive start index of the characters to copy. * @param end * the exclusive end index of the characters to copy. * @param dest * the {@code char[]} to copy the characters to. * @param destStart * the inclusive start index of {@code dest} to begin copying to. * @throws IndexOutOfBoundsException * if the {@code start} is negative, the {@code destStart} is * negative, the {@code start} is greater than {@code end}, the * {@code end} is greater than the current {@link #length()} or * {@code destStart + end - begin} is greater than * {@code dest.length}. */ public void getChars(int start, int end, char[] dest, int destStart) { if (start > count || end > count || start > end) { throw new java.lang.StringIndexOutOfBoundsException(); } JUniversalHelper.arraycopy(value, start, dest, destStart, end - start); } final void insert0(int index, char[] chars) { if (0 > index || index > count) { throw new java.lang.StringIndexOutOfBoundsException(index); } if (chars.length != 0) { move(chars.length, index); JUniversalHelper.arraycopy(chars, 0, value, index, chars.length); count += chars.length; } } final void insert0(int index, char[] chars, int start, int length) { if (0 <= index && index <= count) { // start + length could overflow, start/length maybe MaxInt if (start >= 0 && 0 <= length && length <= chars.length - start) { if (length != 0) { move(length, index); JUniversalHelper.arraycopy(chars, start, value, index, length); count += length; } return; } throw new java.lang.StringIndexOutOfBoundsException("offset " + start //$NON-NLS-1$ + ", length " + length //$NON-NLS-1$ + ", char[].length " + chars.length); //$NON-NLS-1$ } throw new java.lang.StringIndexOutOfBoundsException(index); } final void insert0(int index, char ch) { if (0 > index || index > count) { // RI compatible exception type throw new java.lang.ArrayIndexOutOfBoundsException(index); } move(1, index); value[index] = ch; count++; } final void insert0(int index, String string) { if (0 <= index && index <= count) { if (string == null) { string = "null"; //$NON-NLS-1$ } int min = string.length(); if (min != 0) { move(min, index); string.getChars(0, min, value, index); count += min; } } else { throw new java.lang.StringIndexOutOfBoundsException(index); } } final void insert0(int index, CharSequence s, int start, int end) { if (s == null) { s = "null"; //$NON-NLS-1$ } if (index < 0 || index > count || start < 0 || end < 0 || start > end || end > s.length()) { throw new java.lang.IndexOutOfBoundsException(); } insert0(index, s.subSequence(start, end).toString()); } /** * The current length. * * @return the number of characters contained in this instance. */ public int length() { return count; } private void move(int size, int index) { int newSize; if (value.length - count >= size) { if (!shared) { JUniversalHelper.arraycopy(value, index, value, index + size, count - index); // index == count case is no-op return; } newSize = value.length; } else { int a = count + size, b = (value.length << 1) + 2; newSize = a > b ? a : b; } char[] newData = new char[newSize]; JUniversalHelper.arraycopy(value, 0, newData, 0, index); // index == count case is no-op JUniversalHelper.arraycopy(value, index, newData, index + size, count - index); value = newData; shared = false; } final void replace0(int start, int end, String string) { if (start >= 0) { if (end > count) { end = count; } if (end > start) { int stringLength = string.length(); int diff = end - start - stringLength; if (diff > 0) { // replacing with fewer characters if (!shared) { // index == count case is no-op JUniversalHelper.arraycopy(value, end, value, start + stringLength, count - end); } else { char[] newData = new char[value.length]; JUniversalHelper.arraycopy(value, 0, newData, 0, start); // index == count case is no-op JUniversalHelper.arraycopy(value, end, newData, start + stringLength, count - end); value = newData; shared = false; } } else if (diff < 0) { // replacing with more characters...need some room move(-diff, end); } else if (shared) { value = value.clone(); shared = false; } string.getChars(0, stringLength, value, start); count -= diff; return; } if (start == end) { if (string == null) { throw new NullPointerException(); } insert0(start, string); return; } } throw new java.lang.StringIndexOutOfBoundsException(); } final void reverse0() { if (count < 2) { return; } if (!shared) { int end = count - 1; char frontHigh = value[0]; char endLow = value[end]; boolean allowFrontSur = true, allowEndSur = true; for (int i = 0, mid = count / 2; i < mid; i++, --end) { char frontLow = value[i + 1]; char endHigh = value[end - 1]; boolean surAtFront = allowFrontSur && frontLow >= 0xdc00 && frontLow <= 0xdfff && frontHigh >= 0xd800 && frontHigh <= 0xdbff; if (surAtFront && (count < 3)) { return; } boolean surAtEnd = allowEndSur && endHigh >= 0xd800 && endHigh <= 0xdbff && endLow >= 0xdc00 && endLow <= 0xdfff; allowFrontSur = allowEndSur = true; if (surAtFront == surAtEnd) { if (surAtFront) { // both surrogates value[end] = frontLow; value[end - 1] = frontHigh; value[i] = endHigh; value[i + 1] = endLow; frontHigh = value[i + 2]; endLow = value[end - 2]; i++; end--; } else { // neither surrogates value[end] = frontHigh; value[i] = endLow; frontHigh = frontLow; endLow = endHigh; } } else { if (surAtFront) { // surrogate only at the front value[end] = frontLow; value[i] = endLow; endLow = endHigh; allowFrontSur = false; } else { // surrogate only at the end value[end] = frontHigh; value[i] = endHigh; frontHigh = frontLow; allowEndSur = false; } } } if ((count & 1) == 1 && (!allowFrontSur || !allowEndSur)) { value[end] = allowFrontSur ? endLow : frontHigh; } } else { char[] newData = new char[value.length]; for (int i = 0, end = count; i < count; i++) { char high = value[i]; if ((i + 1) < count && high >= 0xd800 && high <= 0xdbff) { char low = value[i + 1]; if (low >= 0xdc00 && low <= 0xdfff) { newData[--end] = low; i++; } } newData[--end] = high; } value = newData; shared = false; } } /** * Sets the character at the {@code index}. * * @param index * the zero-based index of the character to replace. * @param ch * the character to set. * @throws IndexOutOfBoundsException * if {@code index} is negative or greater than or equal to the * current {@link #length()}. */ public void setCharAt(int index, char ch) { if (0 > index || index >= count) { throw new java.lang.StringIndexOutOfBoundsException(index); } if (shared) { value = value.clone(); shared = false; } value[index] = ch; } /** * Sets the current length to a new value. If the new length is larger than * the current length, then the new characters at the end of this object * will contain the {@code char} value of {@code \u0000}. * * @param length * the new length of this StringBuffer. * @exception IndexOutOfBoundsException * if {@code length < 0}. * @see #length */ public void setLength(int length) { if (length < 0) { throw new java.lang.StringIndexOutOfBoundsException(length); } if (length > value.length) { enlargeBuffer(length); } else { if (shared) { char[] newData = new char[value.length]; JUniversalHelper.arraycopy(value, newData, count); value = newData; shared = false; } else { if (count < length) { for (int i = count; i < length; ++i) value[i] = (char) 0; } } } count = length; } /** * Returns the String value of the subsequence from the {@code start} index * to the current end. * * @param start * the inclusive start index to begin the subsequence. * @return a String containing the subsequence. * @throws StringIndexOutOfBoundsException * if {@code start} is negative or greater than the current * {@link #length()}. */ public String substring(int start) { if (0 <= start && start <= count) { if (start == count) { return ""; //$NON-NLS-1$ } // Remove String sharing for more performance return new String(value, start, count - start); } throw new java.lang.StringIndexOutOfBoundsException(start); } /** * Returns the String value of the subsequence from the {@code start} index * to the {@code end} index. * * @param start * the inclusive start index to begin the subsequence. * @param end * the exclusive end index to end the subsequence. * @return a String containing the subsequence. * @throws StringIndexOutOfBoundsException * if {@code start} is negative, greater than {@code end} or if * {@code end} is greater than the current {@link #length()}. */ public String substring(int start, int end) { if (0 <= start && start <= end && end <= count) { if (start == end) { return ""; //$NON-NLS-1$ } // Remove String sharing for more performance return new String(value, start, end - start); } throw new java.lang.StringIndexOutOfBoundsException(); } /** * Returns the current String representation. * * JUniversal CHANGE: Made so always creates a new string, that's never shared * * @return a String containing the characters in this instance. */ @Override public String toString() { if (count == 0) { return ""; //$NON-NLS-1$ } return new String(value, 0, count); } /** * Returns a {@code CharSequence} of the subsequence from the {@code start} * index to the {@code end} index. * * @param start * the inclusive start index to begin the subsequence. * @param end * the exclusive end index to end the subsequence. * @return a CharSequence containing the subsequence. * @throws IndexOutOfBoundsException * if {@code start} is negative, greater than {@code end} or if * {@code end} is greater than the current {@link #length()}. * @since 1.4 */ public CharSequence subSequence(int start, int end) { return substring(start, end); } /** * Searches for the first index of the specified character. The search for * the character starts at the beginning and moves towards the end. * * @param string * the string to find. * @return the index of the specified character, -1 if the character isn't * found. * @see #lastIndexOf(String) * @since 1.4 */ public int indexOf(String string) { return indexOf(string, 0); } /** * Searches for the index of the specified character. The search for the * character starts at the specified offset and moves towards the end. * * @param subString * the string to find. * @param start * the starting offset. * @return the index of the specified character, -1 if the character isn't * found * @see #lastIndexOf(String,int) * @since 1.4 */ public int indexOf(String subString, int start) { if (start < 0) { start = 0; } int subCount = subString.length(); if (subCount > 0) { if (subCount + start > count) { return -1; } // TODO optimize charAt to direct array access char firstChar = subString.charAt(0); while (true) { int i = start; boolean found = false; for (; i < count; i++) { if (value[i] == firstChar) { found = true; break; } } if (!found || subCount + i > count) { return -1; // handles subCount > count || start >= count } int o1 = i, o2 = 0; while (++o2 < subCount && value[++o1] == subString.charAt(o2)) { // Intentionally empty } if (o2 == subCount) { return i; } start = i + 1; } } return (start < count || start == 0) ? start : count; } /** * Searches for the last index of the specified character. The search for * the character starts at the end and moves towards the beginning. * * @param string * the string to find. * @return the index of the specified character, -1 if the character isn't * found. * @throws NullPointerException * if {@code string} is {@code null}. * @see String#lastIndexOf(java.lang.String) * @since 1.4 */ public int lastIndexOf(String string) { return lastIndexOf(string, count); } /** * Searches for the index of the specified character. The search for the * character starts at the specified offset and moves towards the beginning. * * @param subString * the string to find. * @param start * the starting offset. * @return the index of the specified character, -1 if the character isn't * found. * @throws NullPointerException * if {@code subString} is {@code null}. * @see String#lastIndexOf(String,int) * @since 1.4 */ public int lastIndexOf(String subString, int start) { int subCount = subString.length(); if (subCount <= count && start >= 0) { if (subCount > 0) { if (start > count - subCount) { start = count - subCount; // count and subCount are both } // >= 1 // TODO optimize charAt to direct array access char firstChar = subString.charAt(0); while (true) { int i = start; boolean found = false; for (; i >= 0; --i) { if (value[i] == firstChar) { found = true; break; } } if (!found) { return -1; } int o1 = i, o2 = 0; while (++o2 < subCount && value[++o1] == subString.charAt(o2)) { // Intentionally empty } if (o2 == subCount) { return i; } start = i - 1; } } return start < count ? start : count; } return -1; } /** * Trims off any extra capacity beyond the current length. Note, this method * is NOT guaranteed to change the capacity of this object. * * @since 1.5 */ public void trimToSize() { if (count < value.length) { char[] newValue = new char[count]; JUniversalHelper.arraycopy(value, newValue, count); value = newValue; shared = false; } } }