/*
* The MIT License
*
* Copyright (c) 2004-2009, Sun Microsystems, Inc., Kohsuke Kawaguchi
*
* 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 hudson.scheduler;
import antlr.ANTLRException;
import antlr.LLkParser;
import antlr.ParserSharedInputState;
import antlr.SemanticException;
import antlr.Token;
import antlr.TokenBuffer;
import antlr.TokenStream;
import antlr.TokenStreamException;
/**
* @author Kohsuke Kawaguchi
*/
abstract class BaseParser extends LLkParser {
// lower/uppser bounds of fields (inclusive)
static final int[] LOWER_BOUNDS = new int[] {0,0,1,1,0};
static final int[] UPPER_BOUNDS = new int[] {59,23,31,12,7};
/**
* Used to pick a value from within the range
*/
protected Hash hash = Hash.zero();
protected BaseParser(int i) {
super(i);
}
protected BaseParser(ParserSharedInputState parserSharedInputState, int i) {
super(parserSharedInputState, i);
}
protected BaseParser(TokenBuffer tokenBuffer, int i) {
super(tokenBuffer, i);
}
protected BaseParser(TokenStream tokenStream, int i) {
super(tokenStream, i);
}
public void setHash(Hash hash) {
if (hash==null) hash = Hash.zero();
this.hash = hash;
}
protected long doRange(int start, int end, int step, int field) throws ANTLRException {
rangeCheck(start, field);
rangeCheck(end, field);
if (step <= 0)
error(Messages.BaseParser_MustBePositive(step));
if (start>end)
error(Messages.BaseParser_StartEndReversed(end,start));
long bits = 0;
for (int i = start; i <= end; i += step) {
bits |= 1L << i;
}
return bits;
}
protected long doRange( int step, int field ) throws ANTLRException {
return doRange( LOWER_BOUNDS[field], UPPER_BOUNDS[field], step, field );
}
/**
* Uses {@link Hash} to choose a random (but stable) value from within this field.
*/
protected long doHash( int field ) {
int u = UPPER_BOUNDS[field];
if (field==2) u = 28; // day of month can vary depending on month, so to make life simpler, just use [1,28] that's always safe
if (field==4) u = 6; // Both 0 and 7 of day of week are Sunday. For better distribution, limit upper bound to 6
int h = hash.next(u+1 - LOWER_BOUNDS[field]); // upper bound is inclusive
return 1L << (h+LOWER_BOUNDS[field]);
}
protected long doHash( int s, int e ) {
return 1L << (s+hash.next(e+1-s));
}
protected void rangeCheck(int value, int field) throws ANTLRException {
if( value<LOWER_BOUNDS[field] || UPPER_BOUNDS[field]<value ) {
error(Messages.BaseParser_OutOfRange(value,LOWER_BOUNDS[field],UPPER_BOUNDS[field]));
}
}
private void error(String msg) throws TokenStreamException, SemanticException {
Token token = LT(0);
throw new SemanticException(
msg,
token.getFilename(),
token.getLine(),
token.getColumn()
);
}
protected Hash getHashForTokens() {
return HASH_TOKENS ? hash : Hash.zero();
}
/**
* This property hashes tokens in the cron tab tokens like @daily so that they spread evenly.
* This is more aggressive optimization that changes the semantics, so not on by default.
*/
public static boolean HASH_TOKENS = Boolean.getBoolean(BaseParser.class.getName()+".hash");
}