/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
* indicated by the @author tags or express copyright attribution
* statements applied by the authors. All third-party contributions are
* distributed under license by Red Hat Middleware LLC.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program 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 Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*
*/
package org.hibernate.engine.query.spi;
import org.hibernate.QueryException;
import org.hibernate.hql.internal.classic.ParserHelper;
import org.hibernate.internal.util.StringHelper;
/**
* The single available method {@link #parse} is responsible for parsing a
* query string and recognizing tokens in relation to parameters (either
* named, JPA-style, or ordinal) and providing callbacks about such
* recognitions.
*
* @author Steve Ebersole
*/
public class ParameterParser {
public static interface Recognizer {
public void outParameter(int position);
public void ordinalParameter(int position);
public void namedParameter(String name, int position);
public void jpaPositionalParameter(String name, int position);
public void other(char character);
}
/**
* Direct instantiation of ParameterParser disallowed.
*/
private ParameterParser() {
}
/**
* Performs the actual parsing and tokenizing of the query string making appropriate
* callbacks to the given recognizer upon recognition of the various tokens.
* <p/>
* Note that currently, this only knows how to deal with a single output
* parameter (for callable statements). If we later add support for
* multiple output params, this, obviously, needs to change.
*
* @param sqlString The string to be parsed/tokenized.
* @param recognizer The thing which handles recognition events.
* @throws QueryException Indicates unexpected parameter conditions.
*/
public static void parse(String sqlString, Recognizer recognizer) throws QueryException {
boolean hasMainOutputParameter = startsWithEscapeCallTemplate( sqlString );
boolean foundMainOutputParam = false;
int stringLength = sqlString.length();
boolean inQuote = false;
for ( int indx = 0; indx < stringLength; indx++ ) {
char c = sqlString.charAt( indx );
if ( inQuote ) {
if ( '\'' == c ) {
inQuote = false;
}
recognizer.other( c );
}
else if ( '\'' == c ) {
inQuote = true;
recognizer.other( c );
}
else if ( '\\' == c ) {
// skip sending the backslash and instead send then next character, treating is as a literal
recognizer.other( sqlString.charAt( ++indx ) );
}
else {
if ( c == ':' ) {
// named parameter
int right = StringHelper.firstIndexOfChar( sqlString, ParserHelper.HQL_SEPARATORS, indx + 1 );
int chopLocation = right < 0 ? sqlString.length() : right;
String param = sqlString.substring( indx + 1, chopLocation );
if ( StringHelper.isEmpty( param ) ) {
throw new QueryException(
"Space is not allowed after parameter prefix ':' [" + sqlString + "]"
);
}
recognizer.namedParameter( param, indx );
indx = chopLocation - 1;
}
else if ( c == '?' ) {
// could be either an ordinal or JPA-positional parameter
if ( indx < stringLength - 1 && Character.isDigit( sqlString.charAt( indx + 1 ) ) ) {
// a peek ahead showed this as an JPA-positional parameter
int right = StringHelper.firstIndexOfChar( sqlString, ParserHelper.HQL_SEPARATORS, indx + 1 );
int chopLocation = right < 0 ? sqlString.length() : right;
String param = sqlString.substring( indx + 1, chopLocation );
// make sure this "name" is an integral
try {
Integer.valueOf( param );
}
catch( NumberFormatException e ) {
throw new QueryException( "JPA-style positional param was not an integral ordinal" );
}
recognizer.jpaPositionalParameter( param, indx );
indx = chopLocation - 1;
}
else {
if ( hasMainOutputParameter && !foundMainOutputParam ) {
foundMainOutputParam = true;
recognizer.outParameter( indx );
}
else {
recognizer.ordinalParameter( indx );
}
}
}
else {
recognizer.other( c );
}
}
}
}
public static boolean startsWithEscapeCallTemplate(String sqlString) {
if ( ! ( sqlString.startsWith( "{" ) && sqlString.endsWith( "}" ) ) ) {
return false;
}
int chopLocation = sqlString.indexOf( "call" );
if ( chopLocation <= 0 ) {
return false;
}
final String checkString = sqlString.substring( 1, chopLocation + 4 );
final String fixture = "?=call";
int fixturePosition = 0;
boolean matches = true;
for ( int i = 0, max = checkString.length(); i < max; i++ ) {
final char c = Character.toLowerCase( checkString.charAt( i ) );
if ( Character.isWhitespace( c ) ) {
continue;
}
if ( c == fixture.charAt( fixturePosition ) ) {
fixturePosition++;
continue;
}
matches = false;
break;
}
return matches;
}
}