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 * 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   *
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 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
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package org.apache.james.mime4j.stream;

/**
 * A descriptor containing common MIME content properties.
 */
public interface ContentDescriptor {

    /**
     * Returns the body descriptors MIME type.
     * @see #getMediaType()
     * @see #getSubType()
     * @return The MIME type, which has been parsed from the
     *   content-type definition. Must not be null, but
     *   "text/plain", if no content-type was specified.
     */
    String getMimeType();

    /**
     * Gets the defaulted MIME media type for this content.
     * For example <code>TEXT</code>, <code>IMAGE</code>, <code>MULTIPART</code>
     * @see #getMimeType()
     * @return the MIME media type when content-type specified,
     * otherwise the correct default (<code>TEXT</code>)
     */
    String getMediaType();

    /**
     * Gets the defaulted MIME sub type for this content.
     * @see #getMimeType()
     * @return the MIME media type when content-type is specified,
     * otherwise the correct default (<code>PLAIN</code>)
     */
    String getSubType();

    /**
     * <p>The body descriptors character set, defaulted appropriately for the MIME type.</p>
     * <p>
     * For <code>TEXT</code> types, this will be defaulted to <code>us-ascii</code>.
     * For other types, when the charset parameter is missing this property will be null.
     * </p>
     * @return Character set, which has been parsed from the
     *   content-type definition. Not null for <code>TEXT</code> types, when unset will
     *   be set to default <code>us-ascii</code>. For other types, when unset,
     *   null will be returned.
     */
    String getCharset();

    /**
     * Returns the body descriptors transfer encoding.
     * @return The transfer encoding. Must not be null, but "7bit",
     *   if no transfer-encoding was specified.
     */
    String getTransferEncoding();

    /**
     * Returns the body descriptors content-length.
     * @return Content length, if known, or -1, to indicate the absence of a
     *   content-length header.
     */
    long getContentLength();

}
