--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/parser/UnicodeReader.java Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,285 @@
+/*
+ * Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package com.sun.tools.javac.parser;
+
+import java.nio.CharBuffer;
+import java.util.Arrays;
+
+import com.sun.tools.javac.file.JavacFileManager;
+import com.sun.tools.javac.resources.CompilerProperties.Errors;
+import com.sun.tools.javac.util.ArrayUtils;
+import com.sun.tools.javac.util.Log;
+import com.sun.tools.javac.util.Name;
+import com.sun.tools.javac.util.Names;
+
+import static com.sun.tools.javac.util.LayoutCharacters.*;
+
+/** The char reader used by the javac lexer/tokenizer. Returns the sequence of
+ * characters contained in the input stream, handling unicode escape accordingly.
+ * Additionally, it provides features for saving chars into a buffer and to retrieve
+ * them at a later stage.
+ *
+ * <p><b>This is NOT part of any supported API.
+ * If you write code that depends on this, you do so at your own risk.
+ * This code and its internal interfaces are subject to change or
+ * deletion without notice.</b>
+ */
+public class UnicodeReader {
+
+ /** The input buffer, index of next character to be read,
+ * index of one past last character in buffer.
+ */
+ protected char[] buf;
+ protected int bp;
+ protected final int buflen;
+
+ /** The current character.
+ */
+ protected char ch;
+
+ /** The buffer index of the last converted unicode character
+ */
+ protected int unicodeConversionBp = -1;
+
+ protected Log log;
+ protected Names names;
+
+ /** A character buffer for saved chars.
+ */
+ protected char[] sbuf = new char[128];
+ protected int sp;
+
+ /**
+ * Create a scanner from the input array. This method might
+ * modify the array. To avoid copying the input array, ensure
+ * that {@code inputLength < input.length} or
+ * {@code input[input.length -1]} is a white space character.
+ *
+ * @param sf the factory which created this Scanner
+ * @param buffer the input, might be modified
+ * Must be positive and less than or equal to input.length.
+ */
+ protected UnicodeReader(ScannerFactory sf, CharBuffer buffer) {
+ this(sf, JavacFileManager.toArray(buffer), buffer.limit());
+ }
+
+ protected UnicodeReader(ScannerFactory sf, char[] input, int inputLength) {
+ log = sf.log;
+ names = sf.names;
+ if (inputLength == input.length) {
+ if (input.length > 0 && Character.isWhitespace(input[input.length - 1])) {
+ inputLength--;
+ } else {
+ input = Arrays.copyOf(input, inputLength + 1);
+ }
+ }
+ buf = input;
+ buflen = inputLength;
+ buf[buflen] = EOI;
+ bp = -1;
+ scanChar();
+ }
+
+ /** Read next character.
+ */
+ protected void scanChar() {
+ if (bp < buflen) {
+ ch = buf[++bp];
+ if (ch == '\\') {
+ convertUnicode();
+ }
+ }
+ }
+
+ /** Read next character in comment, skipping over double '\' characters.
+ */
+ protected void scanCommentChar() {
+ scanChar();
+ if (ch == '\\') {
+ if (peekChar() == '\\' && !isUnicode()) {
+ skipChar();
+ } else {
+ convertUnicode();
+ }
+ }
+ }
+
+ /** Append a character to sbuf.
+ */
+ protected void putChar(char ch, boolean scan) {
+ sbuf = ArrayUtils.ensureCapacity(sbuf, sp);
+ sbuf[sp++] = ch;
+ if (scan)
+ scanChar();
+ }
+
+ protected void putChar(char ch) {
+ putChar(ch, false);
+ }
+
+ protected void putChar(boolean scan) {
+ putChar(ch, scan);
+ }
+
+ Name name() {
+ return names.fromChars(sbuf, 0, sp);
+ }
+
+ String chars() {
+ return new String(sbuf, 0, sp);
+ }
+
+ /** Convert unicode escape; bp points to initial '\' character
+ * (Spec 3.3).
+ */
+ protected void convertUnicode() {
+ if (ch == '\\' && unicodeConversionBp != bp) {
+ bp++; ch = buf[bp];
+ if (ch == 'u') {
+ do {
+ bp++; ch = buf[bp];
+ } while (ch == 'u');
+ int limit = bp + 3;
+ if (limit < buflen) {
+ int d = digit(bp, 16);
+ int code = d;
+ while (bp < limit && d >= 0) {
+ bp++; ch = buf[bp];
+ d = digit(bp, 16);
+ code = (code << 4) + d;
+ }
+ if (d >= 0) {
+ ch = (char)code;
+ unicodeConversionBp = bp;
+ return;
+ }
+ }
+ log.error(bp, Errors.IllegalUnicodeEsc);
+ } else {
+ bp--;
+ ch = '\\';
+ }
+ }
+ }
+
+ /** Are surrogates supported?
+ */
+ final static boolean surrogatesSupported = surrogatesSupported();
+ private static boolean surrogatesSupported() {
+ try {
+ Character.isHighSurrogate('a');
+ return true;
+ } catch (NoSuchMethodError ex) {
+ return false;
+ }
+ }
+
+ /** Scan surrogate pairs. If 'ch' is a high surrogate and
+ * the next character is a low surrogate, returns the code point
+ * constructed from these surrogates. Otherwise, returns -1.
+ * This method will not consume any of the characters.
+ */
+ protected int peekSurrogates() {
+ if (surrogatesSupported && Character.isHighSurrogate(ch)) {
+ char high = ch;
+ int prevBP = bp;
+
+ scanChar();
+
+ char low = ch;
+
+ ch = high;
+ bp = prevBP;
+
+ if (Character.isLowSurrogate(low)) {
+ return Character.toCodePoint(high, low);
+ }
+ }
+
+ return -1;
+ }
+
+ /** Convert an ASCII digit from its base (8, 10, or 16)
+ * to its value.
+ */
+ protected int digit(int pos, int base) {
+ char c = ch;
+ if ('0' <= c && c <= '9')
+ return Character.digit(c, base); //a fast common case
+ int codePoint = peekSurrogates();
+ int result = codePoint >= 0 ? Character.digit(codePoint, base) : Character.digit(c, base);
+ if (result >= 0 && c > 0x7f) {
+ log.error(pos + 1, Errors.IllegalNonasciiDigit);
+ if (codePoint >= 0)
+ scanChar();
+ ch = "0123456789abcdef".charAt(result);
+ }
+ return result;
+ }
+
+ protected boolean isUnicode() {
+ return unicodeConversionBp == bp;
+ }
+
+ protected void skipChar() {
+ bp++;
+ }
+
+ protected char peekChar() {
+ return buf[bp + 1];
+ }
+
+ /**
+ * Returns a copy of the input buffer, up to its inputLength.
+ * Unicode escape sequences are not translated.
+ */
+ public char[] getRawCharacters() {
+ char[] chars = new char[buflen];
+ System.arraycopy(buf, 0, chars, 0, buflen);
+ return chars;
+ }
+
+ /**
+ * Returns a copy of a character array subset of the input buffer.
+ * The returned array begins at the {@code beginIndex} and
+ * extends to the character at index {@code endIndex - 1}.
+ * Thus the length of the substring is {@code endIndex-beginIndex}.
+ * This behavior is like
+ * {@code String.substring(beginIndex, endIndex)}.
+ * Unicode escape sequences are not translated.
+ *
+ * @param beginIndex the beginning index, inclusive.
+ * @param endIndex the ending index, exclusive.
+ * @throws ArrayIndexOutOfBoundsException if either offset is outside of the
+ * array bounds
+ */
+ public char[] getRawCharacters(int beginIndex, int endIndex) {
+ int length = endIndex - beginIndex;
+ char[] chars = new char[length];
+ System.arraycopy(buf, beginIndex, chars, 0, length);
+ return chars;
+ }
+}