// $Id: ASTAppender.java 7460 2005-07-12 20:27:29Z steveebersole $
package org.hibernate.hql.ast.util;
import antlr.ASTFactory;
import antlr.collections.AST;
/**
* Appends child nodes to a parent efficiently.
*
* @author josh Jul 24, 2004 8:28:23 AM
*/
public class ASTAppender {
private AST parent;
private AST last;
private ASTFactory factory;
public ASTAppender(ASTFactory factory, AST parent) {
this( parent );
this.factory = factory;
}
public ASTAppender(AST parent) {
this.parent = parent;
this.last = ASTUtil.getLastChild( parent );
}
public AST append(int type, String text, boolean appendIfEmpty) {
if ( text != null && ( appendIfEmpty || text.length() > 0 ) ) {
return append( factory.create( type, text ) );
}
else {
return null;
}
}
public AST append(AST child) {
if ( last == null ) {
parent.setFirstChild( child );
}
else {
last.setNextSibling( child );
}
last = child;
return last;
}
}
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