Pipeline.java

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package streamer;

/**
 * Pipeline groups multiple elements.
 */
public interface Pipeline extends Element {

    static final String IN = Direction.IN.toString();
    static final String OUT = Direction.OUT.toString();

    /**
     * Add elements to pipeline.
     *
     * @param elements
     */
    void add(Element... elements);

    /**
     * Add elements to pipeline and link them in given order.
     *
     * @param elements
     */
    void addAndLink(Element... elements);

    /**
     * Link elements in given order using SyncLink. Element name can have prefix
     * "PADNAME< " or/and suffix " >PADNAME" to use given named pads instead of
     * "stdin" and "stdout". I.e. <code>link("foo", "bar", "baz");</code> is equal
     * to <code>link("foo >stdin", "stdout< bar >stdin", "stdout< baz");</code> .
     *
     * Special elements "IN" and "OUT" are pointing to pipeline outer interfaces,
     * so when pipeline will be connected with other elements, outside of this
     * pipeline, they will be connected to IN and OUT elements.
     *
     * Empty names are skipped.
     *
     * Example:
     *
     * <pre>
     * pipeline.link("IN", "foo", "bar", "OUT");
     * // Make additional branch from foo to baz, and then to OUT
     * pipeline.link("foo >baz_out", "baz", "baz_in< OUT");
     * </pre>
     *
     * @param elements
     *          elements to link
     */
    void link(String... elements);

    /**
     * Get element by name.
     *
     * @return an element
     */
    Element get(String elementName);

    /**
     * Get link by element name and pad name.
     */
    Link getLink(String elementName, String padName);

    /**
     * Set link by element name and pad name. Allows to link external elements
     * into internal elements of pipeline. Special elements "IN" and "OUT" are
     * pointing to pipeline outer interfaces.
     */
    void setLink(String elementName, String padName, Link link, Direction direction);

    /**
     * Get link connected to given pad in given element and run it main loop.
     * @param separateThread
     *          set to true to start main loop in separate thread.
     * @param waitForStartEvent TODO
     */
    void runMainLoop(String element, String padName, boolean separateThread, boolean waitForStartEvent);

}