# COSBoolean.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.cos;

    import java.io.IOException;
    import java.io.OutputStream;

    /**
     * This class represents a boolean value in the PDF document.
     *
     * @author Ben Litchfield
     */
    public final class COSBoolean extends COSBase
    {
        /**
         * The true boolean token.
         */
        private static final byte[] TRUE_BYTES = new byte[] { 116, 114, 117, 101 }; // "true".getBytes("ISO-8859-1")
        /**
         * The false boolean token.
         */
        private static final byte[] FALSE_BYTES = new byte[] { 102, 97, 108, 115, 101 }; // "false".getBytes("ISO-8859-1")

        /**
         * The PDF true value.
         */
        public static final COSBoolean TRUE = new COSBoolean( true );

        /**
         * The PDF false value.
         */
        public static final COSBoolean FALSE = new COSBoolean( false );

        private final boolean value;

        /**
         * Constructor.
         *
         * @param aValue The boolean value.
         */
        private COSBoolean(boolean aValue)
        {
            value = aValue;
        }

        /**
         * This will get the value that this object wraps.
         *
         * @return The boolean value of this object.
         */
        public boolean getValue()
        {
            return value;
        }

        /**
         * This will get the value that this object wraps.
         *
         * @return The boolean value of this object.
         */
        public Boolean getValueAsObject()
        {
            return value ? Boolean.TRUE : Boolean.FALSE;
        }

        /**
         * This will get the boolean value.
         *
         * @param value Parameter telling which boolean value to get.
         *
         * @return The single boolean instance that matches the parameter.
         */
        public static COSBoolean getBoolean( boolean value )
        {
            return value ? TRUE : FALSE;
        }

        /**
         * This will get the boolean value.
         *
         * @param value Parameter telling which boolean value to get.
         *
         * @return The single boolean instance that matches the parameter.
         */
        public static COSBoolean getBoolean( Boolean value )
        {
            return getBoolean( value.booleanValue() );
        }

        /**
         * visitor pattern double dispatch method.
         *
         * @param visitor The object to notify when visiting this object.
         * @throws IOException If an error occurs while visiting this object.
         */
        @Override
        public void accept(ICOSVisitor visitor) throws IOException
        {
            visitor.visitFromBoolean(this);
        }

        /**
         * Return a string representation of this object.
         *
         * @return The string value of this object.
         */
        @Override
        public String toString()
        {
            return String.valueOf( value );
        }

        /**
         * {@inheritDoc}
         */
        @Override
        public int hashCode() {
            //taken from java.lang.Boolean
            return value ? 1231 : 1237;
        }

        /**
         * {@inheritDoc}
         */
        public boolean equals(Object obj) {
            if (obj instanceof COSBoolean) {
                return value == ((COSBoolean)obj).getValue();
            }
            return false;
        }

        /**
         * This will write this object out to a PDF stream.
         *
         * @param output The stream to write this object out to.
         *
         * @throws IOException If an error occurs while writing out this object.
         */
        public void writePDF( OutputStream output ) throws IOException
        {
            if( value )
            {
                output.write( TRUE_BYTES );
            }
            else
            {
                output.write( FALSE_BYTES );
            }
        }
    }