package org.eclipse.dltk.internal.ui;


/**
 * A browser input contains an input element and
 * a previous and a next input, if available.
 *
 * The browser input also provides a human readable
 * name of its input element.
 *
 * @since 3.4
 */
public abstract class BrowserInput {

	private final BrowserInput fPrevious;
	private BrowserInput fNext;

	/**
	 * Create a new Browser input.
	 *
	 * @param previous the input previous to this or <code>null</code> if this is the first
	 */
	public BrowserInput(BrowserInput previous) {
		fPrevious= previous;
		if (previous != null)
			previous.fNext= this;
	}

	/**
	 * The previous input or <code>null</code> if this
	 * is the first.
	 *
	 * @return the previous input or <code>null</code>
	 */
	public BrowserInput getPrevious() {
		return fPrevious;
	}

	/**
	 * The next input or <code>null</code> if this
	 * is the last.
	 *
	 * @return the next input or <code>null</code>
	 */
	public BrowserInput getNext() {
		return fNext;
	}

	/**
	 * The element to use to set the browsers input.
	 *
	 * @return the input element
	 */
	public abstract Object getInputElement();

	/**
	 * A human readable name for the input.
	 *
	 * @return the input name
	 */
	public abstract String getInputName();
}