com.sun.jsftemplating.util.LayoutElementUtil Maven / Gradle / Ivy
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the License). You may not use this file except in
* compliance with the License.
*
* You can obtain a copy of the license at
* https://jsftemplating.dev.java.net/cddl1.html or
* jsftemplating/cddl1.txt.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* Header Notice in each file and include the License file
* at jsftemplating/cddl1.txt.
* If applicable, add the following below the CDDL Header,
* with the fields enclosed by brackets [] replaced by
* you own identifying information:
* "Portions Copyrighted [year] [name of copyright owner]"
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
*/
package com.sun.jsftemplating.util;
import com.sun.jsftemplating.layout.descriptors.LayoutComponent;
import com.sun.jsftemplating.layout.descriptors.LayoutElement;
import com.sun.jsftemplating.layout.descriptors.LayoutFacet;
import java.util.Iterator;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import javax.faces.context.FacesContext;
/**
* This class is a utility class for misc {@link LayoutElement} related
* tasks.
*
* @author Ken Paulsen ([email protected])
*/
public class LayoutElementUtil {
/**
* This method determines if the given {@link LayoutElement} is
* inside a {@link LayoutComponent}. It will look at all the
* parents, if any of them are {@link LayoutComponent} instances,
* this method will return true.
*
* @param elt The {@link LayoutElement} to check.
*
* @return true If a {@link LayoutComponent} exists as an ancestor.
*/
public static boolean isNestedLayoutComponent(LayoutElement elt) {
return (getParentLayoutComponent(elt) != null);
}
/**
* This method returns the nearest {@link LayoutComponent} that
* contains the given {@link LayoutElement}, null if none.
*
* @param elt The {@link LayoutElement} to start with.
*
* @return The containing {@link LayoutComponent} if one exists.
*/
public static LayoutComponent getParentLayoutComponent(LayoutElement elt) {
elt = elt.getParent();
while (elt != null) {
if (elt instanceof LayoutComponent) {
return (LayoutComponent) elt;
}
elt = elt.getParent();
}
return null;
}
/**
* This method returns true if any of the parent
* {@link LayoutElement}s are {@link LayoutComponent}s. If a
* {@link LayoutFacet} is encountered first, false is automatically
* returned. This method is specific to processing needed for
* creating a {@link LayoutComponent}. Do not use this for general
* cases when you need to find if a {@link LayoutElement} is embedded
* within a {@link LayoutComponent} (which should ignore
* {@link LayoutFacet} elements).
*
* @param elt The {@link LayoutElement} to check.
*
* @return true if it has a {@link LayoutComponent} ancestor.
*/
public static boolean isLayoutComponentChild(LayoutElement elt) {
elt = elt.getParent();
while (elt != null) {
if (elt instanceof LayoutComponent) {
// Make sure we are in a LayoutComponent and not an "if",
// "while", or something like that
if (elt.getClass().getName().equals(
LayoutComponent.CLASS_NAME)) {
// This is a real LayoutComponent, return true
return true;
}
// This isn't a LC, however, we need to count it as such if
// there is any LC parent (even if we encounter a LayoutFacet
// first)
return isNestedLayoutComponent(elt);
} else if (elt instanceof LayoutFacet) {
// Don't consider it a child if it is a facet
return false;
}
elt = elt.getParent();
}
// Not found
return false;
}
/**
* This method produces a generated ID. It optionally uses the given
* base as a prefix to the generated ID ({@link #DEFAULT_ID_BASE} is
* used otherwise). Do not depend on this implementation, it may
* change in the future.
*
* Since this implementation increments the number each call, it may
* not produce reproducible results. You should pass in
* your own number to use, see {@link #getGeneratedId(String, int)}.
* JSFT makes an effort to cause generated ids to be reproducible
* accross requests, but it is not guarenteed (particularly in highly
* dynamic pages in development mode).
*/
public static String getGeneratedId(String base) {
return getGeneratedId(base, incHighestId(_highId));
}
/**
* This method produces a generated ID. It optionally uses the given
* base as a prefix to the generated ID ({@link #DEFAULT_ID_BASE} is
* used otherwise). This implementation will generate an id that
* contains the given number. Do not depend result of this this
* implementation, it may change in the future.
*
* This method replaces illegal characters (all non alpha characters)
* with an '_'.
*
* @param base Prefix to use in the id.
* @param num Number to use in the id.
*/
public static String getGeneratedId(String base, int num) {
if (base == null) {
base = DEFAULT_ID_BASE;
} else {
base = base.trim();
if (base.equals("")) {
base = DEFAULT_ID_BASE;
} else {
StringBuffer buf = new StringBuffer();
int lowch;
for (int ch : base.toCharArray()) {
lowch = ch | 0x20;
if ((lowch >= 'a') && (lowch <= 'z')) {
buf.append((char) ch);
} else {
buf.append('_');
}
}
base = buf.toString();
}
}
return base + num;
}
/**
* This method returns the next id that has not been used.
*/
public static int getStartingIdNumber(FacesContext ctx, String key) {
if (ctx == null) {
// Make sure we have the FacesContext...
ctx = FacesContext.getCurrentInstance();
}
Map startMap = null;
if (ctx != null) {
// Check Application Scope for the Map...
startMap = (Map) ctx.getExternalContext().
getApplicationMap().get(ID_IDX_MAP);
}
if (startMap == null) {
// Not found, 1st time... create / initialize it
startMap = new ConcurrentHashMap(50, 0.75f, 3);
if (ctx != null) {
// Save for later
ctx.getExternalContext().getApplicationMap().
put(ID_IDX_MAP, startMap);
}
}
// Now look for the desired start key...
Integer start = startMap.get(key);
if (start == null) {
// Save for later
// FIXME: Why do I need _highId? Isn't key+0 good enough?
start = incHighestId(_highId);
startMap.put(key, start);
}
// Return the answer...
return start;
}
/**
* This method ensures the highest id is higher than the given
* int.
*/
public static synchronized int incHighestId(int num) {
if (num >= _highId) {
_highId = num + 1;
}
return _highId;
}
/**
* This method checks to see if the given component is
* sitting inside a facet or not. If it is, it will use the facet
* name for its id so that it will be found correctly. However, if
* the facet tag exists outside a component, then it is not a facet
* -- its a place holder for a facet. In this case it will not use
* the id of the place holder.
*/
public static void checkForFacetChild(LayoutElement parent, LayoutComponent component) {
// Figure out if this should be stored as a facet, if so under what id
if (!LayoutElementUtil.isLayoutComponentChild(component)) {
// Need to add this so that it has the correct facet name
// Check to see if this LayoutComponent is inside a LayoutFacet
String id = component.getUnevaluatedId();
while (parent != null) {
if (parent instanceof LayoutFacet) {
// Inside a LayoutFacet, use its id... only if this facet
// is a child of a LayoutComponent (otherwise, it is a
// layout facet used for layout, not for defining a facet
// of a UIComponent)
if (LayoutElementUtil.isLayoutComponentChild(parent)) {
id = parent.getUnevaluatedId();
}
break;
}
parent = parent.getParent();
}
// Set the facet name
component.addOption(LayoutComponent.FACET_NAME, id);
}
}
/**
* This method recurses through the {@link LayoutElement} tree to
* generate a String representation of its structure.
*/
public static void dumpTree(LayoutElement elt, StringBuffer buf, String indent) {
// First add the current LayoutElement
String compInfo = "";
if (elt instanceof LayoutComponent) {
LayoutComponent comp = (LayoutComponent) elt;
compInfo = " nested=" + comp.isNested();
} else if (elt instanceof LayoutFacet) {
compInfo = " isRendered=" + ((LayoutFacet) elt).isRendered();
}
buf.append(indent + elt.getUnevaluatedId() + " (" + elt.getClass().getName() + ")" + compInfo + "\n");
// Children...
Iterator it = elt.getChildLayoutElements().iterator();
if (it.hasNext()) {
while (it.hasNext()) {
dumpTree(it.next(), buf, indent + " ");
}
}
}
/**
* Application scope key for the id index Map.
*/
private static final String ID_IDX_MAP = "__jsft_ID_Index_Map";
// May need to make this application-scoped...
private static int _highId = 0;
public static final String DEFAULT_ID_BASE = "id";
}