# SetGraphicsStateParameters.java

    /*
     * Licensed to the Apache Software Foundation (ASF) under one or more
     * contributor license agreements.  See the NOTICE file distributed with
     * this work for additional information regarding copyright ownership.
     * The ASF licenses this file to You under the Apache License, Version 2.0
     * (the "License"); you may not use this file except in compliance with
     * the License.  You may obtain a copy of the License at
     *
     *      http://www.apache.org/licenses/LICENSE-2.0
     *
     * Unless required by applicable law or agreed to in writing, software
     * distributed under the License is distributed on an "AS IS" BASIS,
     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     * See the License for the specific language governing permissions and
     * limitations under the License.
     */
    package org.apache.pdfbox.contentstream.operator.state;

    import java.io.IOException;
    import java.util.List;

    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;
    import org.apache.pdfbox.cos.COSBase;
    import org.apache.pdfbox.cos.COSName;
    import org.apache.pdfbox.pdmodel.graphics.state.PDExtendedGraphicsState;
    import org.apache.pdfbox.contentstream.operator.Operator;
    import org.apache.pdfbox.contentstream.operator.OperatorName;
    import org.apache.pdfbox.contentstream.operator.OperatorProcessor;
    import org.apache.pdfbox.contentstream.operator.MissingOperandException;

    /**
     * gs: Set parameters from graphics state parameter dictionary.
     *
     * @author Ben Litchfield
     */
    public class SetGraphicsStateParameters extends OperatorProcessor
    {
        private static final Log LOG = LogFactory.getLog(SetGraphicsStateParameters.class);

        @Override
        public void process(Operator operator, List<COSBase> arguments) throws IOException
        {
            if (arguments.isEmpty())
            {
                throw new MissingOperandException(operator, arguments);
            }
            COSBase base0 = arguments.get(0);
            if (!(base0 instanceof COSName))
            {
                return;
            }

            // set parameters from graphics state parameter dictionary
            COSName graphicsName = (COSName) base0;
            PDExtendedGraphicsState gs = context.getResources().getExtGState(graphicsName);
            if (gs == null)
            {
                LOG.error("name for 'gs' operator not found in resources: /" + graphicsName.getName());
                return;
            }
            gs.copyIntoGraphicsState( context.getGraphicsState() );
        }

        @Override
        public String getName()
        {
            return OperatorName.SET_GRAPHICS_STATE_PARAMS;
        }
    }