/*******************************************************************************
* Copyright (c) 2000, 2016 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.help.internal.context;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExtensionRegistry;
import org.eclipse.core.runtime.Platform;
import org.eclipse.help.AbstractContextProvider;
import org.eclipse.help.IContext;
import org.eclipse.help.internal.HelpPlugin;
/*
* Manages all context-sensitive help data for the help system.
*/
public class ContextManager {
private static final String EXTENSION_POINT_ID_CONTEXT = HelpPlugin.PLUGIN_ID + ".contexts"; //$NON-NLS-1$
private static final String ELEMENT_NAME_CONTEXT_PROVIDER = "contextProvider"; //$NON-NLS-1$
private static final String ATTRIBUTE_NAME_CLASS = "class"; //$NON-NLS-1$
private Map<String, List<AbstractContextProvider>> providersByPluginId;
private Map<String, List<String>> contextIDsByPluginId;
private List<AbstractContextProvider> globalProviders;
public ContextManager()
{
if (HelpPlugin.DEBUG_CONTEXT)
checkContextProviders();
}
/*
* Returns the Context for the given id and locale.
*/
public IContext getContext(String contextId, String locale) {
if (HelpPlugin.DEBUG_CONTEXT && contextId != null) {
System.out.println("ContextManager.getContext(\"" + contextId + "\")"); //$NON-NLS-1$ //$NON-NLS-2$
}
// ask the providers
int index = contextId.lastIndexOf('.');
if (index != -1) {
String pluginId = contextId.substring(0, index);
Iterator<AbstractContextProvider> iter = getContextProviders(pluginId).iterator();
while (iter.hasNext()) {
AbstractContextProvider provider = iter.next();
try {
IContext context = provider.getContext(contextId, locale);
if (context != null) {
if (HelpPlugin.DEBUG_CONTEXT) {
System.out.println("ContextManager.getContext found context, description = \"" + context.getText() + '"'); //$NON-NLS-1$
}
return new Context(context, contextId);
}
}
catch (Throwable t) {
// log and skip
String msg = "Error querying context provider (" + provider.getClass().getName() + ") with context Id: " + contextId; //$NON-NLS-1$ //$NON-NLS-2$
HelpPlugin.logError(msg, t);
}
}
}
if (HelpPlugin.DEBUG_CONTEXT) {
System.out.println("ContextManager.getContext - no context found"); //$NON-NLS-1$
String id = contextId;
ArrayList<String> potentialMatches = new ArrayList<>();
if ((index = contextId.lastIndexOf('.'))>-1)
id = contextId.substring(index+1);
String warning = "Registered Context Provider IDs:\n"; //$NON-NLS-1$
Iterator<String> iter = contextIDsByPluginId.keySet().iterator();
warning+="--------------------------------\n"; //$NON-NLS-1$
while (iter.hasNext()) {
String pluginID = iter.next();
List<String> contextIDList = contextIDsByPluginId.get(pluginID);
for (int c = 0; c < contextIDList.size(); c++) {
if (contextIDList.get(c).equalsIgnoreCase(id)) {
potentialMatches.add(pluginID+'.'+contextIDList.get(c));
break;
}
}
warning+=pluginID+' '+contextIDList.toString()+'\n';
}
warning+="--------------------------------"; //$NON-NLS-1$
System.out.println(warning);
if (!potentialMatches.isEmpty())
System.out.println("The ID searched is "+contextId+". Did you mean to call setHelp with:\n"+potentialMatches); //$NON-NLS-1$ //$NON-NLS-2$
}
return null;
}
/*
* Returns all registered context providers (potentially cached) for the
* given plug-in id.
*/
private List<AbstractContextProvider> getContextProviders(String pluginId) {
if (providersByPluginId == null) {
loadContextProviders();
}
List<AbstractContextProvider> list = new ArrayList<>();
List<AbstractContextProvider> forPlugin = providersByPluginId.get(pluginId);
if (forPlugin != null) {
list.addAll(forPlugin);
}
list.addAll(globalProviders);
return list;
}
/*
* Finds and instantiates all registered context-sensitive help providers.
*/
private void loadContextProviders() {
providersByPluginId = new HashMap<>();
globalProviders = new ArrayList<>();
IExtensionRegistry registry = Platform.getExtensionRegistry();
IConfigurationElement[] elements = registry.getConfigurationElementsFor(EXTENSION_POINT_ID_CONTEXT);
for (int i=0;i<elements.length;++i) {
IConfigurationElement elem = elements[i];
if (elem.getName().equals(ELEMENT_NAME_CONTEXT_PROVIDER)) {
try {
AbstractContextProvider provider = (AbstractContextProvider)elem.createExecutableExtension(ATTRIBUTE_NAME_CLASS);
String[] plugins = provider.getPlugins();
if (plugins != null) {
for (int j=0;j<plugins.length;++j) {
List<AbstractContextProvider> list = providersByPluginId.get(plugins[j]);
if (list == null) {
list = new ArrayList<>();
providersByPluginId.put(plugins[j], list);
}
list.add(provider);
}
} else {
globalProviders.add(provider);
}
}
catch (CoreException e) {
// log and skip
String msg = "Error instantiating context-sensitive help provider class \"" + elem.getAttribute(ATTRIBUTE_NAME_CLASS) + '"'; //$NON-NLS-1$
HelpPlugin.logError(msg, e);
}
}
}
}
/*
* Method only called when debugging context
* sensitive help.
*
* Checks to see if there are any duplicate ids
*
*/
private void checkContextProviders()
{
contextIDsByPluginId = new Hashtable<>();
Hashtable<String, Context> contextByContextID = new Hashtable<>();
if (providersByPluginId == null) {
loadContextProviders();
}
Iterator<String> i = providersByPluginId.keySet().iterator();
while (i.hasNext())
{
String pluginID = i.next();
List<AbstractContextProvider> providers = providersByPluginId.get(pluginID);
for (int p = 0; p < providers.size(); p++) {
ContextFileProvider provider = (ContextFileProvider)providers.get(p);
Map<String, Context>[] maps = provider.getPluginContexts(pluginID, Platform.getNL());
for (int m = 0; m < maps.length; m++) {
Iterator<String> i2 = maps[m].keySet().iterator();
while (i2.hasNext()) {
String contextID = i2.next();
String fullID = pluginID+'.'+contextID;
Context currentContext = maps[m].get(contextID);
if (!contextByContextID.containsKey(fullID)) {
contextByContextID.put(fullID,currentContext);
} else if (HelpPlugin.DEBUG_CONTEXT) {
Context initialContext = contextByContextID.get(fullID);
String error = "Context Help ID '"+contextID+"' is found in multiple context files in plugin '"+pluginID+"'\n"+ //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
" Description 1: "+initialContext.getText()+'\n'+ //$NON-NLS-1$
" Description 2: "+currentContext.getText(); //$NON-NLS-1$
System.out.println(error);
}
List<String> list = contextIDsByPluginId.get(pluginID);
if (list==null){
list = new ArrayList<>();
contextIDsByPluginId.put(pluginID,list);
}
list.add(contextID);
}
}
}
}
}
}