Java并发编程: 常用的分布式锁总结

一、基于MySQL的分布式锁

主要利用到了MySQL中select + for update操作来达到互斥的效果。

public static <T> T lockWithMutex(String lockName, DataSource dataSource, Callable<T> runnable) throws Exception {
        Connection connection = null;
        boolean autoCommit = false;
        PreparedStatement stmt = null;
        long start = System.currentTimeMillis();
        T result;
        try {
            connection = dataSource.getConnection();
            autoCommit = connection.getAutoCommit();
            connection.setAutoCommit(false);
            stmt = connection.prepareStatement("SELECT lock_name FROM lock WHERE lock_name = '" + lockName + "' FOR UPDATE");
            stmt.execute();
            result = runnable.call();
        } catch (Exception exception) {
            log.error("operation with mutex fail", exception);
            throw exception;
        } finally {
            releaseMutex(stmt, connection, autoCommit);
        }
        return result;
    }
 private static void releaseMutex(PreparedStatement stmt, Connection connection, boolean autoCommit) {
        if (stmt != null) {
            try {
                stmt.close();
            } catch (SQLException e) {
                log.error("error occurred while closing prepared statement", e);
            }
        }

        if (connection != null) {
            try {
                connection.commit();
            } catch (SQLException e) {
                log.error("error occurred while committing transaction", e);
            }
            try {
                connection.setAutoCommit(autoCommit);
            } catch (SQLException e) {
                log.error("error occurred while setting auto commit property of connection", e);
            }
            try {
                connection.close();
            } catch (SQLException e) {
                log.error("error occurred while closing connection", e);
            }
        }
    }