noargsqlfunction.java

hibernate-distribution-3.3.1.GA-dist.zip源码

/*
 * 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.dialect.function;

import java.util.List;

import org.hibernate.QueryException;
import org.hibernate.engine.Mapping;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.type.Type;


/**
 * A function which takes no arguments
 * @author Michi
 */
public class NoArgSQLFunction implements SQLFunction {
    private Type returnType;
    private boolean hasParenthesesIfNoArguments;
    private String name;

    public NoArgSQLFunction(String name, Type returnType) {
        this(name, returnType, true);
    }

    public NoArgSQLFunction(String name, Type returnType, boolean hasParenthesesIfNoArguments) {
        this.returnType = returnType;
        this.hasParenthesesIfNoArguments = hasParenthesesIfNoArguments;
        this.name = name;
    }

    public Type getReturnType(Type columnType, Mapping mapping) throws QueryException {
        return returnType;
    }

    public boolean hasArguments() {
        return false;
    }

    public boolean hasParenthesesIfNoArguments() {
        return hasParenthesesIfNoArguments;
    }
    
    public String render(List args, SessionFactoryImplementor factory) throws QueryException {
    	if ( args.size()>0 ) {
    		throw new QueryException("function takes no arguments: " + name);
    	}
    	return hasParenthesesIfNoArguments ? name + "()" : name;
    }
}