dom/src/main/java/org/apache/james/mime4j/field/ContentTransferEncodingFieldImpl.java

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 * 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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package org.apache.james.mime4j.field;

import java.util.Locale;

import org.apache.james.mime4j.codec.DecodeMonitor;
import org.apache.james.mime4j.dom.FieldParser;
import org.apache.james.mime4j.dom.field.ContentTransferEncodingField;
import org.apache.james.mime4j.stream.Field;
import org.apache.james.mime4j.util.MimeUtil;

/**
 * Represents a <code>Content-Transfer-Encoding</code> field.
 */
public class ContentTransferEncodingFieldImpl extends AbstractField implements ContentTransferEncodingField {

    private boolean parsed = false;
    private String encoding;

    ContentTransferEncodingFieldImpl(Field rawField, DecodeMonitor monitor) {
        super(rawField, monitor);
    }

    private void parse() {
        parsed = true;
        String body = getBody();
        if (body != null) {
            encoding = body.trim().toLowerCase(Locale.US);
        } else {
            encoding = null;
        }
    }

    /**
     * @see org.apache.james.mime4j.dom.field.ContentTransferEncodingField#getEncoding()
     */
    public String getEncoding() {
        if (!parsed) {
            parse();
        }
        return encoding;
    }

    /**
     * Gets the encoding of the given field if. Returns the default
     * <code>7bit</code> if not set or if <code>f</code> is
     * <code>null</code>.
     *
     * @return the encoding.
     */
    public static String getEncoding(ContentTransferEncodingField f) {
        if (f != null && f.getEncoding().length() != 0) {
            return f.getEncoding();
        }
        return MimeUtil.ENC_7BIT;
    }

    public static final FieldParser<ContentTransferEncodingField> PARSER = new FieldParser<ContentTransferEncodingField>() {

        public ContentTransferEncodingField parse(final Field rawField, final DecodeMonitor monitor) {
            return new ContentTransferEncodingFieldImpl(rawField, monitor);
        }

    };
}