FooterLine.java

/*
 * Copyright (C) 2009, Google Inc. and others
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0 which is available at
 * https://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

package org.eclipse.jgit.revwalk;

import java.nio.charset.Charset;

import org.eclipse.jgit.util.RawParseUtils;

/**
 * Single line at the end of a message, such as a "Signed-off-by: someone".
 * <p>
 * These footer lines tend to be used to represent additional information about
 * a commit, like the path it followed through reviewers before finally being
 * accepted into the project's main repository as an immutable commit.
 *
 * @see RevCommit#getFooterLines()
 */
public final class FooterLine {
    private final byte[] buffer;

    private final Charset enc;

    private final int keyStart;

    private final int keyEnd;

    private final int valStart;

    private final int valEnd;

    FooterLine(final byte[] b, final Charset e, final int ks, final int ke,
            final int vs, final int ve) {
        buffer = b;
        enc = e;
        keyStart = ks;
        keyEnd = ke;
        valStart = vs;
        valEnd = ve;
    }

    /**
     * Whether keys match
     *
     * @param key
     *            key to test this line's key name against.
     * @return true if {@code key.getName().equalsIgnorecase(getKey())}.
     */
    public boolean matches(FooterKey key) {
        final byte[] kRaw = key.raw;
        final int len = kRaw.length;
        int bPtr = keyStart;
        if (keyEnd - bPtr != len)
            return false;
        for (int kPtr = 0; kPtr < len;) {
            byte b = buffer[bPtr++];
            if ('A' <= b && b <= 'Z')
                b += (byte) ('a' - 'A');
            if (b != kRaw[kPtr++])
                return false;
        }
        return true;
    }

    /**
     * Get key name of this footer.
     *
     * @return key name of this footer; that is the text before the ":" on the
     *         line footer's line. The text is decoded according to the commit's
     *         specified (or assumed) character encoding.
     */
    public String getKey() {
        return RawParseUtils.decode(enc, buffer, keyStart, keyEnd);
    }

    /**
     * Get value of this footer.
     *
     * @return value of this footer; that is the text after the ":" and any
     *         leading whitespace has been skipped. May be the empty string if
     *         the footer has no value (line ended with ":"). The text is
     *         decoded according to the commit's specified (or assumed)
     *         character encoding.
     */
    public String getValue() {
        return RawParseUtils.decode(enc, buffer, valStart, valEnd);
    }

    /**
     * Extract the email address (if present) from the footer.
     * <p>
     * If there is an email address looking string inside of angle brackets
     * (e.g. "&lt;a@b&gt;"), the return value is the part extracted from inside the
     * brackets. If no brackets are found, then {@link #getValue()} is returned
     * if the value contains an '@' sign. Otherwise, null.
     *
     * @return email address appearing in the value of this footer, or null.
     */
    public String getEmailAddress() {
        final int lt = RawParseUtils.nextLF(buffer, valStart, '<');
        if (valEnd <= lt) {
            final int at = RawParseUtils.nextLF(buffer, valStart, '@');
            if (valStart < at && at < valEnd)
                return getValue();
            return null;
        }
        final int gt = RawParseUtils.nextLF(buffer, lt, '>');
        if (valEnd < gt)
            return null;
        return RawParseUtils.decode(enc, buffer, lt, gt - 1);
    }

    /** {@inheritDoc} */
    @Override
    public String toString() {
        return getKey() + ": " + getValue(); //$NON-NLS-1$
    }
}