org.apache.pdfbox.util.PDFOperator Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of pdfbox Show documentation
The Apache PDFBox library is an open source Java tool for working with PDF documents.
There is a newer version: 3.0.2
/*
 * 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.util;

import java.util.concurrent.ConcurrentHashMap;

/**
 * This class represents an Operator in the content stream.
 *
 * @author Ben Litchfield
 * @version $Revision: 1.14 $
 */
public class PDFOperator
{
    private String theOperator;
    private byte[] imageData;
    private ImageParameters imageParameters;

    /** map for singleton operator objects; use {@link ConcurrentHashMap} for better scalability with multiple threads */
    private final static ConcurrentHashMap operators = new ConcurrentHashMap();

    /**
     * Constructor.
     *
     * @param aOperator The operator that this object will represent.
     */
    private PDFOperator( String aOperator )
    {
        theOperator = aOperator;
        if( aOperator.startsWith( "/" ) )
        {
            throw new RuntimeException( "Operators are not allowed to start with / '" + aOperator + "'" );
        }
    }

    /**
     * This is used to create/cache operators in the system.
     *
     * @param operator The operator for the system.
     *
     * @return The operator that matches the operator keyword.
     */
    public static PDFOperator getOperator( String operator )
    {
        PDFOperator operation = null;
        if( operator.equals( "ID" ) || operator.equals( "BI" ) )
        {
            //we can't cache the ID operators.
            operation = new PDFOperator( operator );
        }
        else
        {
            operation = operators.get( operator );
            if( operation == null )
            {
                // another thread may has already added an operator of this kind
                // make sure that we get the same operator
                operation = operators.putIfAbsent( operator, new PDFOperator( operator ) );
                if ( operation == null )
                {
                    operation = operators.get( operator );
                }
            }
        }

        return operation;
    }

    /**
     * This will get the operation that this operator represents.
     *
     * @return The string representation of the operation.
     */
    public String getOperation()
    {
        return theOperator;
    }

    /**
     * This will print a string rep of this class.
     *
     * @return A string rep of this class.
     */
    public String toString()
    {
        return "PDFOperator{" + theOperator + "}";
    }

    /**
     * This is the special case for the ID operator where there are just random
     * bytes inlined the stream.
     *
     * @return Value of property imageData.
     */
    public byte[] getImageData()
    {
        return this.imageData;
    }

    /**
     * This will set the image data, this is only used for the ID operator.
     *
     * @param imageDataArray New value of property imageData.
     */
    public void setImageData(byte[] imageDataArray)
    {
        imageData = imageDataArray;
    }

    /**
     * This will get the image parameters, this is only valid for BI operators.
     *
     * @return The image parameters.
     */
    public ImageParameters getImageParameters()
    {
        return imageParameters;
    }

    /**
     * This will set the image parameters, this is only valid for BI operators.
     *
     * @param params The image parameters.
     */
    public void setImageParameters( ImageParameters params)
    {
        imageParameters = params;
    }
}