Function.java example

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/* ================================================================
 * JSQLParser : java based sql parser 
 * ================================================================
 *
 * Project Info:  http://jsqlparser.sourceforge.net
 * Project Lead:  Leonardo Francalanci (leoonardoo@yahoo.it);
 *
 * (C) Copyright 2004, by Leonardo Francalanci
 *
 * This library is free software; you can redistribute it and/or modify it under the terms
 * of the GNU Lesser General Public License as published by the Free Software Foundation;
 * either version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 */

package net.sf.jsqlparser.expression;

import net.sf.jsqlparser.expression.operators.relational.ExpressionList;

/**
 * A function as MAX,COUNT...
 */
public class Function implements Expression {

	private String name;
	private ExpressionList parameters;
	private boolean allColumns = false;
	private boolean distinct = false;
	private boolean isEscaped = false;
	
	public void accept(ExpressionVisitor expressionVisitor) {
		expressionVisitor.visit(this);
	}
	
	/**
	 * The name of he function, i.e. "MAX"
	 * @return the name of he function
	 */
	public String getName() {
		return name;
	}

	public void setName(String string) {
		name = string;
	}

	/**
	 * true if the parameter to the function is "*"
	 * @return true if the parameter to the function is "*"
	 */
	public boolean isAllColumns() {
		return allColumns;
	}

	public void setAllColumns(boolean b) {
		allColumns = b;
	}

	/**
	 * true if the function is "distinct"
	 * @return true if the function is "distinct"
	 */
	public boolean isDistinct() {
		return distinct;
	}

	public void setDistinct(boolean b) {
		distinct = b;
	}

	/**
	 * The list of parameters of the function (if any, else null)
	 * If the parameter is "*", allColumns is set to true
	 * @return the list of parameters of the function (if any, else null)
	 */
	public ExpressionList getParameters() {
		return parameters;
	}

	public void setParameters(ExpressionList list) {
		parameters = list;
	}

    /**
     * Return true if it's in the form "{fn function_body() }" 
     * @return true if it's java-escaped
     */
    public boolean isEscaped() {
        return isEscaped;
    }
    
    public void setEscaped(boolean isEscaped) {
        this.isEscaped = isEscaped;
    }

    public String toString() {
    	String params = "";
    	
    	if(allColumns) {
    		params = "(*)";
    	}
    	else if(parameters != null) {
			params = parameters.toString();
    		if (isDistinct()) {
    			params = params.replaceFirst("\\(", "(DISTINCT ");
    		} 
    	}
    	
    	String ans = name+""+params+"";
    	
    	if(isEscaped) {
    		ans = "{fn "+ans+"}"; 
    	}
    	
    	return ans;
    }
}