Application: gvSIG desktop

package org.gvsig.expressionevaluator.impl.function.string;

import java.util.Objects;

import org.apache.commons.lang3.Range;

import static org.gvsig.expressionevaluator.ExpressionBuilder.FUNCTION_CONCAT;

import org.gvsig.expressionevaluator.Interpreter;

import org.gvsig.expressionevaluator.spi.AbstractFunction;

public class ConcatFunction extends AbstractFunction {

    public ConcatFunction() {

        super("String", FUNCTION_CONCAT, Range.between(1,Integer.MAX_VALUE));

    }

    @Override

    public boolean allowConstantFolding() {

        return true;

    }

    @Override

    public Object call(Interpreter interpreter, Object[] args) throws Exception {

        StringBuilder builder = new StringBuilder();

        for( Object arg : args ) {

            if( arg != null ) {

                builder.append(Objects.toString(arg, ""));

            }

        }

        return builder.toString();

    }

}