/* Path.java{{IS_NOTE	Purpose:			Description:			History:		Thu Jan 19 14:07:44     2006, Created by tomyeh}}IS_NOTECopyright (C) 2006 Potix Corporation. All Rights Reserved.{{IS_RIGHT	This program is distributed under GPL Version 2.0 in the hope that	it will be useful, but WITHOUT ANY WARRANTY.}}IS_RIGHT*/package org.zkoss.zk.ui;import java.util.Collection;import org.zkoss.zk.mesg.MZk;import org.zkoss.zk.ui.sys.ComponentsCtrl;import org.zkoss.zk.ui.sys.ExecutionCtrl;/** * A representation of a component path. * * @author tomyeh */public class Path {	private final String _path;	public Path() {		this((String)null);	}	public Path(String path) {		_path = normalize(path);	}	public Path(String parent, String child) {		this(parent == null || parent.length() == 0 ? child:			child == null || child.length() == 0 ? parent:				parent + '/' + child);	}	public Path(Path parent, String child) {		this(parent != null ? parent.getPath(): null, child);	}	/** Returns the path of the specified component. */	public Path(Component comp) {		this(getPath(comp));	}	/** Returns the path (after normalized).	 */	public String getPath() {		return _path;	}	/** Returns the component with this path, or null if no such component.	 */	public Component getComponent() {		return getComponent0(null, _path);	}	/** Returns the path of the specified component.	 */	public static final String getPath(Component comp) {		final StringBuffer sb = new StringBuffer(64);		for (;;) {			if (sb.length() > 0) sb.insert(0, '/');			final String compId = comp.getId();			if (ComponentsCtrl.isAutoId(compId))				throw new UiException(MZk.AUTO_ID_NOT_ALLOWED_IN_PATH, comp);			sb.insert(0, compId);			IdSpace is = comp.getSpaceOwner();			if (is instanceof Page) break; //done			if (is == comp) {				final Component p = ((Component)is).getParent();				if (p == null) break; //topmost				is = p.getSpaceOwner();				if (is instanceof Page) break; //done			}			comp = (Component)is;		}		sb.insert(0, '/');		return sb.toString();	}	/** Returns the component of the specified path, or null if no such component.	 */	public static final Component getComponent(String path) {		return getComponent0(null, normalize(path));	}	/** Returns the component of the specified path which is related	 * to the specified ID space, or null if no such component.	 *	 * @param is the current ID space. It is required only if path is related	 * (in other words, not starting with / or //).	 */	public static final Component getComponent(IdSpace is, String path) {		return getComponent0(is, normalize(path));	}	private static final Component getComponent0(IdSpace is, String path) {		Component found = null;		for (int j = 0, k;; j = k + 1) {			k = path.indexOf('/', j);			if (k == 0) { //starts with /				final Execution exec = Executions.getCurrent();				final Desktop desktop = exec.getDesktop();				Page page = ((ExecutionCtrl)exec).getCurrentPage();				if (page == null) {					final Collection pages = desktop.getPages();					if (pages.isEmpty())						return null;					page = (Page)pages.iterator().next();						//the first page assumed				}				if (path.length() == 1) // "/" only					return getFirstRoot(page); //the first root assumed				if (path.charAt(1) == '/') { //starts with //					k = path.indexOf('/', 2);					if (k < 0)						return getFirstRoot(page); //the first root assumed					final String nm = path.substring(2, k);					is = desktop.getPageIfAny(nm);					if (is == null)						return null; //no such page				} else {					is = page;				}				continue;			}			final String nm = k >= 0 ? path.substring(j, k): path.substring(j);			if ("..".equals(nm)) {				if (!(is instanceof Component))					return null;				final Component c = (Component)is;				final Component p = c.getParent();				is = p != null ? p.getSpaceOwner(): (IdSpace)c.getPage();				if (k < 0) {					return (is instanceof Component) ? (Component)is: null;				}				continue;			}			if (is == null)				return null;			final Component c = is.getFellow(nm);			if (k < 0) return c;			if (!(c instanceof IdSpace))				return null;			is = (IdSpace)c;		}	}	private static Component getFirstRoot(Page page) {		final Collection roots = page.getRoots();		return roots.isEmpty() ? null: (Component)roots.iterator().next();	}	/**	 * Normalizes the giving path.	 * It removes consecutive slahses, ending slahes,	 * redudant . and ..	 */	private static final String normalize(String path) {		if (path == null)			return "";		//remove consecutive slashes		final StringBuffer sb = new StringBuffer(path);		boolean slash = false;		for (int j = 0, len = sb.length(); j < len; ++j) {			final boolean curslash = sb.charAt(j) == '/';			if (curslash && slash && j != 1) {				sb.deleteCharAt(j);				--j; --len;			}			slash = curslash;		}		if (sb.length() > 1 && slash)//remove ending slash except "/"			sb.setLength(sb.length() - 1);		//remove ./		while (sb.length() >= 2 && sb.charAt(0) == '.' && sb.charAt(1) == '/')			sb.delete(0, 2); // "./" -> ""		//remove /./		for (int j = 0; (j = sb.indexOf( "/./", j)) >= 0;)			sb.delete(j + 1, j + 3); // "/./" -> "/"		//ends with "/."		int len = sb.length();		if (len >= 2 && sb.charAt(len - 1) == '.' && sb.charAt(len - 2) == '/')			if (len == 2) return "/";			else sb.delete(len - 2, len);		//remove /../		for (int j = 0; (j = sb.indexOf("/../", j)) >= 0;)			j = removeDotDot(sb, j);		// ends with "/.."		len = sb.length();		if (len >= 3 && sb.charAt(len - 1) == '.' && sb.charAt(len - 2) == '.'		&& sb.charAt(len - 3) == '/') 			if (len == 3) return "/";			else removeDotDot(sb, len - 3);		return sb.length() == path.length() ? path: sb.toString();	}	/** Removes "/..".	 * @param j points '/' in "/.."	 * @return the next index to search from	 */	static private int removeDotDot(StringBuffer sb, int j) {		int k = j;		while (--k >= 0 && sb.charAt(k) != '/') 			;		if (k + 3 == j && sb.charAt(k + 1) == '.' && sb.charAt(k + 2) == '.')			return j + 4; // don't touch: "../.."		sb.delete(j, j + 3); // "/.." -> ""		if (j == 0) // "/.."			return 0;		if (k < 0) { // "a/+" => kill "a/", "a" => kill a			sb.delete(0, j < sb.length() ? j + 1: j);			return 0;		}		// "/a/+" => kill "/a", "/a" => kill "a"		if (j >= sb.length()) ++k;		sb.delete(k, j);		return k;	}	//--Object--//	public boolean equals(Object o) {		return o instanceof Path && ((Path)o)._path.equals(_path);	}	public int hashCode() {		return _path.hashCode();	}	public String toString() {		return _path;	}}