/*
* #!
* Ontopia Navigator
* #-
* Copyright (C) 2001 - 2013 The Ontopia Project
* #-
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* !#
*/
package net.ontopia.topicmaps.nav2.utils;
import java.io.IOException;
import java.io.Writer;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.jsp.PageContext;
import net.ontopia.topicmaps.core.TMObjectIF;
import net.ontopia.topicmaps.core.TopicIF;
import net.ontopia.topicmaps.core.TopicMapIF;
import net.ontopia.topicmaps.nav2.core.NavigatorPageIF;
import net.ontopia.topicmaps.nav2.core.NavigatorRuntimeException;
import net.ontopia.topicmaps.query.core.InvalidQueryException;
import net.ontopia.topicmaps.query.core.ParsedQueryIF;
import net.ontopia.topicmaps.query.core.QueryProcessorIF;
import net.ontopia.topicmaps.query.core.QueryResultIF;
import net.ontopia.topicmaps.query.utils.QueryUtils;
import net.ontopia.topicmaps.utils.TopicTreeNode;
import net.ontopia.utils.OntopiaRuntimeException;
import net.ontopia.utils.StringUtils;
import net.ontopia.utils.CompactHashSet;
/**
* PUBLIC: This class can output a nice collapsing/expanding tree view
* of a topic map which uses tolog queries to produce the tree. The
* class is configurable in various ways, and can also be subclassed
* to further fine-tune the rendering.
*
* @since 2.1
*/
public class TreeWidget {
protected static final int OPEN = 1;
protected static final int CLOSE = 2;
protected static final int EXPAND_ALL = 3;
protected static final int CLOSE_ALL = 4;
protected static final int WINDOW_SIZE = 100;
protected QueryProcessorIF processor;
protected String nodepage;
protected String staticurl;
protected Set openNodes;
protected String imageurl = "";
protected int windowSize = WINDOW_SIZE;
protected NavigatorPageIF context;
protected Collection ancestors;
private String name = "ONTOPIA-WIDGET-ATTRIBUTE";
protected ParsedQueryIF query;
protected TopicMapIF topicmap;
protected Map map = new HashMap();
protected String topquery;
protected String ownpage;
private String querystr; // string repr of query, parsed into 'query'
protected String nodeFrame;
private boolean addAnchor = true;
// --- External interface
/**
* PUBLIC: Sets up the widget ready for use. The default constructor
* must be accompanied by the appropriate setter methods.
*/
public TreeWidget() {
}
/**
* PUBLIC: Sets up the widget ready for use.
*
* @param topicmap The topic map being displayed.
* @param query A tolog query that given a node generates its
* children. Use the %parent% parameter to reference the parent node
* in the query. Make sure the query produces a 1-column result.
* @param topquery A tolog query that generates the list of top
* nodes. Make sure the query produces a 1-column result.
* @param ownpage The URL of the page the widget is on. The widget
* will append request parameters in the form "a=b&c=d&e=f..."
* @param nodepage The URL of of the page that shows the nodes.
*/
public TreeWidget(TopicMapIF topicmap,
String query, String topquery,
String ownpage, String nodepage) {
setTopicMap(topicmap);
this.querystr = query;
this.topquery = topquery;
this.ownpage = ownpage;
this.nodepage = nodepage;
}
/**
* PUBLIC: Sets the topic map used by the widget.
*/
public void setTopicMap(TopicMapIF topicmap) {
this.topicmap = topicmap;
this.processor = QueryUtils.getQueryProcessor(topicmap);
}
/**
* PUBLIC: The name of the session key in which the set of open nodes is
* stored. Using the same session key for different widgets will make them
* share open/closed information.
*/
public void setWidgetName(String name) {
this.name = name;
}
/**
* PUBLIC: Sets the tolog query that generates the list of top
* nodes. Make sure the query produces a 1-column result.
*/
public void setTopQueryString(String topQuery) {
this.topquery = topQuery;
}
/**
* PUBLIC: Sets the tolog query that given a node generates its
* children. Use the %parent% parameter to reference the parent node
* in the query. Make sure the query produces a 1-column result.
*/
public void setNodeQueryString(String nodeQuery) {
this.querystr = nodeQuery;
}
/**
* PUBLIC: The URL of the page the widget is on. The widget will
* append request parameters in the form "a=b&c=d&e=f..."
*/
public void setOwnPageUrl(String ownPageUrl) {
this.ownpage = ownPageUrl;
}
/**
* PUBLIC: The URL of of the page that shows the nodes.
*/
public void setNodePageUrl(String nodePageUrl) {
this.nodepage = nodePageUrl;
}
/**
* PUBLIC: The URL at which the graphics used by the widget are found. The
* widget will produce HTML like <img src="[imageurl]spacer.gif"> to
* refer to the graphics.
*/
public void setImageUrl(String imageurl) {
this.imageurl = imageurl;
}
/**
* PUBLIC: If set to true the widget will add anchors on all links that
* open/close nodes in the tree. The default is true.
*/
public void setAddAnchor(boolean addAnchor) {
this.addAnchor = addAnchor;
}
/**
* PUBLIC: Sets the maximum number of nodes displayed by the widget at once.
* If the number of nodes to display exceeds the maximum the widget will break
* the display into multiple "pages".
*/
public void setWindowSize(int windowSize) {
this.windowSize = windowSize;
}
/**
* PUBLIC: The name of the HTML frame in which to open links to nodes.
*/
public void setNodeFrame(String nodeFrame) {
this.nodeFrame = nodeFrame;
}
/**
* PUBLIC: Runs the widget, producing the output.
*/
public void run(PageContext ctxt, Writer writer) throws IOException,
InvalidQueryException, NavigatorRuntimeException {
run((HttpServletRequest) ctxt.getRequest(), writer);
}
/**
* PUBLIC: Runs the widget, producing the output.
*
* @since 2.2.1
*/
public void run(HttpServletRequest request, Writer writer)
throws IOException, InvalidQueryException, NavigatorRuntimeException {
initializeContext(request);
Map parameters = request.getParameterMap();
parseQueries();
// get current node
TopicIF current = null;
if (parameters.containsKey("current"))
current = getTopic(get(parameters, "current"));
int action = getAction(parameters);
if (action == EXPAND_ALL)
openNodes = new UniversalSet();
else if (action == CLOSE_ALL)
openNodes = new CompactHashSet();
else {
openNodes = getOpenNodes(request);
if (action == OPEN)
openNodes.add(current);
else if (action == CLOSE)
openNodes.remove(current);
}
int topline = 0;
if (parameters.containsKey("topline")) {
try {
topline = Integer.parseInt(get(parameters, "topline"));
} catch (NumberFormatException e) {}
}
try {
doQuery(topline, writer);
} catch (InvalidQueryException e) {
throw new net.ontopia.utils.OntopiaRuntimeException(e);
}
setOpenNodes(request, openNodes);
}
protected void parseQueries() throws InvalidQueryException {
// check that query has been parsed
if (query == null)
query = processor.parse(querystr, context.getDeclarationContext());
}
protected void initializeContext(HttpServletRequest request) {
if (context == null)
context = FrameworkUtils.getContextTag(request);
}
private void doQuery(int topline, Writer writer) throws IOException,
InvalidQueryException {
TopicTreeNode tree = buildTree();
writeHTML(tree, topline, writer);
}
// --- Logic
protected TopicTreeNode buildTree() throws InvalidQueryException {
TopicTreeNode root = new TopicTreeNode(null);
QueryResultIF result = processor.execute(topquery, context
.getDeclarationContext());
while (result.next()) {
TopicIF topic = (TopicIF) result.getValue(0);
TopicTreeNode group = new TopicTreeNode(topic);
group.setParent(root);
group.setAttribute("id", getId(topic));
if (openNodes.contains(topic)) {
ancestors = new ArrayList();
process(group);
if (group.getChildren().isEmpty())
group.setAttribute("action", null);
else
group.setAttribute("action", "close");
openNodes.add(topic);
} else {
// check if there are children
QueryResultIF leaves = getChildren(topic);
if (leaves.next())
group.setAttribute("action", "open");
else
group.setAttribute("action", null);
}
}
return root;
}
protected QueryResultIF getChildren(TopicIF topic) throws InvalidQueryException {
map.put("parent", topic);
return query.execute(map);
}
// --- Reusable
protected void process(TopicTreeNode parent) throws InvalidQueryException {
TopicIF topic = parent.getTopic();
if (ancestors.contains(topic))
return;
ancestors.add(topic);
QueryResultIF children = getChildren(topic);
while (children.next()) {
TopicIF childtopic = (TopicIF) children.getValue(0);
TopicTreeNode child = new TopicTreeNode(childtopic);
child.setAttribute("id", getId(childtopic));
child.setParent(parent);
if (openNodes.contains(childtopic)) {
process(child);
if (!child.getChildren().isEmpty())
child.setAttribute("action", "close");
openNodes.add(childtopic);
} else {
// this one is not open; need to check if it has children
QueryResultIF leaves = getChildren(childtopic);
if (leaves.next())
child.setAttribute("action", "open");
else
child.setAttribute("action", null);
}
}
ancestors.remove(topic);
}
private void writeHTML(TopicTreeNode node, int topline, Writer writer)
throws IOException {
int nodes = countNodes(node);
staticurl = ownpage + "topline=";
startRender(writer);
if (topline > 1)
renderBackButton(writer, topline);
renderExpandAllButton(writer, topline);
renderCloseAllButton(writer, topline);
if (topline + windowSize < nodes)
renderForwardButton(writer, topline);
renderAdditionalOnTopExpandCloseLine(writer, topline);
writer.write("<br><br>\n");
renderTree(node, topline, writer);
if (topline > 1)
renderBackButton(writer, topline);
renderExpandAllButton(writer, topline);
renderCloseAllButton(writer, topline);
if (topline + windowSize < nodes)
renderForwardButton(writer, topline);
renderAdditionalOnBottomExpandCloseLine(writer, topline);
endRender(writer);
}
protected void renderTree(TopicTreeNode node, int topline, Writer writer)
throws IOException {
List children = node.getChildren();
int lineno = 0;
for (int ix = 0; ix < children.size(); ix++)
lineno = writeNode((TopicTreeNode) children.get(ix), topline, writer, 0,
lineno, false);
writer.write("<br>");
}
protected int writeNode(TopicTreeNode node, int topline, Writer writer,
int level, int lineno, boolean indoc) throws IOException {
boolean nextIndoc = indoc;
lineno++;
if (lineno >= topline && lineno <= topline + windowSize) {
String id = (String) node.getAttribute("id");
String action = (String) node.getAttribute("action");
if (action == null)
writer.write("<img border=0 src=" + imageurl + "spacer.gif width="
+ (level * 30) + " height=5>" + "<img border=0 src=" + imageurl
+ "boxed.gif>");
else
renderNodeButton(topline, level, action.equals("open") ? OPEN : CLOSE,
id, writer);
writer.write("<a name=" + id + "></a>");
renderNode(node, writer);
writer.write("<br>\n");
}
if (lineno < topline + windowSize) {
List children = node.getChildren();
for (int ix = 0; ix < children.size(); ix++)
lineno = writeNode((TopicTreeNode) children.get(ix), topline, writer,
level + 1, lineno, nextIndoc);
}
return lineno;
}
// --- Helpers
private int getAction(Map parameters) {
String action = get(parameters, "todo");
if (action == null)
action = "close";
if (action.equals("open"))
return OPEN;
else if (action.equals("close"))
return CLOSE;
else if (action.equals("expandall"))
return EXPAND_ALL;
else if (action.equals("closeall"))
return CLOSE_ALL;
else
return -1;
}
private Set getOpenNodes(HttpServletRequest request) {
String opennodes = (String) request.getSession().getAttribute(name);
if (opennodes == null)
opennodes = "";
return makeSet(StringUtils.split(opennodes, ","));
}
private void setOpenNodes(HttpServletRequest request, Set openNodes) {
request.getSession().setAttribute(name, list(openNodes));
}
// --- Utilities
private Set makeSet(String[] open) {
Set nodes = new CompactHashSet(open.length * 2);
for (int ix = 0; ix < open.length; ix++) {
if (open[ix].equals(""))
continue;
TMObjectIF object = getObjectById(open[ix]);
// if the ID list in the session is out of date, because the
// topic map was reloaded or changed in the meantime, we may
// get non-existent topics or non-topics back here. if this
// happens we assume we have out-of-date info and stop
if (object == null || !(object instanceof TopicIF))
return new CompactHashSet();
nodes.add(object);
}
return nodes;
}
protected String getId(TopicIF topic) {
return NavigatorUtils.getStableId(topic);
}
protected TMObjectIF getObjectById(String id) {
return NavigatorUtils.stringID2Object(topicmap, id);
}
protected TopicIF getTopic(String id) {
return (TopicIF) getObjectById(id);
}
protected String list(Set nodes) {
StringBuilder buf = new StringBuilder();
Iterator it = nodes.iterator();
while (it.hasNext())
buf.append("," + getId((TopicIF) it.next()));
return buf.toString();
}
private String get(Map parameters, String name) {
// the servlets 2.3 spec says the Map should be String -> String[],
// but Oracle 9iAS has String -> String, so we need to code around
// that
Object value = parameters.get(name);
if (value instanceof String) // then your app server is broken
return (String) value;
// else, we continue like normal
String[] values = (String[]) value;
if (values == null)
return null;
return values[0];
}
// NOTE: we *don't* count the root node (it's a false convenience node)
private int countNodes(TopicTreeNode node) {
List children = node.getChildren();
int size = children.size();
int count = 0;
for (int ix = 0; ix < size; ix++)
count += countNodes((TopicTreeNode) children.get(ix));
return count + size;
}
public String toString(TopicIF topic) {
try {
return Stringificator.toString(context, topic);
} catch (NavigatorRuntimeException e) {
throw new OntopiaRuntimeException(e);
}
}
// --- Extension interface
/**
* PUBLIC: This method renders the tree node, including its link, but
* <em>not</em> the button in front of the node. Intended to be overridden
* by applications wanting to control rendering of nodes in detail.
*/
protected void renderNode(TopicTreeNode node, Writer out) throws IOException {
TopicIF topic = node.getTopic();
if (topic != null) {
out.write("<a href='" + makeNodeUrl(node) + "'");
if (nodeFrame != null)
out.write(" target=\"" + nodeFrame + "\"");
out.write(">");
}
out.write(toString(topic));
if (topic != null)
out.write("</a>");
}
/**
* PUBLIC: Renders the +/- button in front of the node. Intended to be
* overridden.
*/
protected void renderNodeButton(int topline, int level, int action,
String id, Writer out) throws IOException {
String image = "expand";
if (action == CLOSE)
image = "collapse";
out.write("<a href=\"" + staticurl + topline + "&todo="
+ (action == OPEN ? "open" : "close") + "¤t=" + id
+ (addAnchor ? ("#" + id) : "") + "\">" + "<img border=0 src="
+ imageurl + "spacer.gif width=" + (level * 30) + " height=5>"
+ "<img border=0 src=" + imageurl + image + ".gif></a>");
}
/**
* PUBLIC: Renders the back button at the top/bottom of the form.
*/
protected void renderBackButton(Writer out, int topline) throws IOException {
out.write("<a href=\"" + staticurl + (topline - windowSize)
+ "\" title='Show previous page'><img border=0 src=" + imageurl
+ "nav_prev.gif></a> ");
}
/**
* PUBLIC: Renders the expand all button at the top/bottom of the form.
*/
protected void renderExpandAllButton(Writer out, int topline)
throws IOException {
out.write("<a href=\"" + ownpage + "topline=" + topline
+ "&todo=expandall\" title='Expand all nodes'><img border=0 src="
+ imageurl + "expand_all.gif></a> ");
}
/**
* PUBLIC: Renders the close all button at the top/bottom of the form.
*/
protected void renderCloseAllButton(Writer out, int topline)
throws IOException {
out.write("<a href=\""
+ ownpage
+ "topline=0&todo=closeall\" title='Collapse all nodes'><img border=0 src="
+ imageurl + "collapse_all.gif></a> ");
}
/**
* PUBLIC: Renders the close all button at the top/bottom of the form.
*/
protected void renderForwardButton(Writer out, int topline)
throws IOException {
out.write("<a href=\"" + staticurl + (topline + windowSize)
+ "\" title='Show next page'><img border=0 src=" + imageurl
+ "nav_next.gif></a>");
}
/**
* PUBLIC: Performs any additional rendering on the top line of the open-all
* and close-all buttons. Intended to be implemented by any sub-classes that
* need to do such additional rendering.
*/
protected void renderAdditionalOnTopExpandCloseLine(Writer out, int topline)
throws IOException {
}
/**
* PUBLIC: Performs any additional rendering on the bottom line of the
* open-all and close-all buttons. Intended to be implemented by any
* sub-classes that need to do such additional rendering.
*/
protected void renderAdditionalOnBottomExpandCloseLine(Writer out,
int topline)
throws IOException {
}
/**
* PUBLIC: Called before rendering of the tree begins.
*/
protected void startRender(Writer out) throws IOException {}
/**
* PUBLIC: Called after the tree has been rendered.
*/
protected void endRender(Writer out) throws IOException {}
/**
* PUBLIC: Produces the URL to the given node.
* @since 3.0
*/
protected String makeNodeUrl(TopicTreeNode node) {
return nodepage + "id=" + getId(node.getTopic());
}
// --- UniversalSet class
// used when the "expand all" button is pressed. claims that all
// topics are open, and since open topics are always added to the
// set it also records which ones are open. this means that during
// the tree traversal phase all nodes are included and added to the
// set, so that when the staticurl is produced later all nodes are
// included in the url. (this is necessary to ensure that the close
// node buttons work as expected.)
// this class is a hack, and therefore defined as an internal class.
protected class UniversalSet extends CompactHashSet {
public boolean contains(Object object) {
return true;
}
}
}