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Java example source code file (ScannerSupport.java)
The ScannerSupport.java Java example source code/* * Permission is hereby granted, free of charge, to any person obtaining a copy of * this software and associated documentation files (the "Software"), to deal in * the Software without restriction, including without limitation the rights to * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies * of the Software, and to permit persons to whom the Software is furnished to do * so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ package jdk.nashorn.internal.runtime.regexp.joni; import jdk.nashorn.internal.runtime.regexp.joni.encoding.IntHolder; import jdk.nashorn.internal.runtime.regexp.joni.exception.ErrorMessages; abstract class ScannerSupport extends IntHolder implements ErrorMessages { protected final char[] chars; // pattern protected int p; // current scanner position protected int stop; // pattern end (mutable) private int lastFetched; // last fetched value for unfetch support protected int c; // current code point private final int begin; // pattern begin position for reset() support private final int end; // pattern end position for reset() support protected int _p; // used by mark()/restore() to mark positions private final static int INT_SIGN_BIT = 1 << 31; protected ScannerSupport(char[] chars, int p, int end) { this.chars = chars; this.begin = p; this.end = end; reset(); } protected int getBegin() { return begin; } protected int getEnd() { return end; } protected final int scanUnsignedNumber() { int last = c; int num = 0; // long ??? while(left()) { fetch(); if (Character.isDigit(c)) { int onum = num; num = num * 10 + EncodingHelper.digitVal(c); if (((onum ^ num) & INT_SIGN_BIT) != 0) return -1; } else { unfetch(); break; } } c = last; return num; } protected final int scanUnsignedHexadecimalNumber(int maxLength) { int last = c; int num = 0; while(left() && maxLength-- != 0) { fetch(); if (EncodingHelper.isXDigit(c)) { int onum = num; int val = EncodingHelper.xdigitVal(c); num = (num << 4) + val; if (((onum ^ num) & INT_SIGN_BIT) != 0) return -1; } else { unfetch(); break; } } c = last; return num; } protected final int scanUnsignedOctalNumber(int maxLength) { int last = c; int num = 0; while(left() && maxLength-- != 0) { fetch(); if (Character.isDigit(c) && c < '8') { int onum = num; int val = EncodingHelper.odigitVal(c); num = (num << 3) + val; if (((onum ^ num) & INT_SIGN_BIT) != 0) return -1; } else { unfetch(); break; } } c = last; return num; } protected final void reset() { p = begin; stop = end; } protected final void mark() { _p = p; } protected final void restore() { p = _p; } protected final void inc() { lastFetched = p; p++; } protected final void fetch() { lastFetched = p; c = chars[p++]; } protected int fetchTo() { lastFetched = p; return chars[p++]; } protected final void unfetch() { p = lastFetched; } protected final int peek() { return p < stop ? chars[p] : 0; } protected final boolean peekIs(int c) { return peek() == c; } protected final boolean left() { return p < stop; } } Other Java examples (source code examples)Here is a short list of links related to this Java ScannerSupport.java source code file: |
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