org.hibernate.hql.ast.util.PathHelper Maven / Gradle / Ivy
/*
* 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
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*
*/
package org.hibernate.hql.ast.util;
import org.hibernate.hql.antlr.HqlSqlTokenTypes;
import org.hibernate.util.StringHelper;
import antlr.ASTFactory;
import antlr.collections.AST;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Provides utility methods for paths.
*
* @author josh
*/
public final class PathHelper {
private static final Logger log = LoggerFactory.getLogger( PathHelper.class );
private PathHelper() {
}
/**
* Turns a path into an AST.
*
* @param path The path.
* @param factory The AST factory to use.
* @return An HQL AST representing the path.
*/
public static AST parsePath(String path, ASTFactory factory) {
String[] identifiers = StringHelper.split( ".", path );
AST lhs = null;
for ( int i = 0; i < identifiers.length; i++ ) {
String identifier = identifiers[i];
AST child = ASTUtil.create( factory, HqlSqlTokenTypes.IDENT, identifier );
if ( i == 0 ) {
lhs = child;
}
else {
lhs = ASTUtil.createBinarySubtree( factory, HqlSqlTokenTypes.DOT, ".", lhs, child );
}
}
if ( log.isDebugEnabled() ) {
log.debug( "parsePath() : " + path + " -> " + ASTUtil.getDebugString( lhs ) );
}
return lhs;
}
public static String getAlias(String path) {
return StringHelper.root( path );
}
}