/*******************************************************************************
* 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
* Stefan Liebig - Bug 242685 StringVariableManager - Variable contributions may silently override existing variables
*******************************************************************************/
package org.eclipse.core.internal.variables;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExtensionPoint;
import org.eclipse.core.runtime.ISafeRunnable;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.ListenerList;
import org.eclipse.core.runtime.MultiStatus;
import org.eclipse.core.runtime.Platform;
import org.eclipse.core.runtime.SafeRunner;
import org.eclipse.core.runtime.Status;
import org.eclipse.core.runtime.preferences.IEclipsePreferences;
import org.eclipse.core.runtime.preferences.IEclipsePreferences.IPreferenceChangeListener;
import org.eclipse.core.runtime.preferences.IEclipsePreferences.PreferenceChangeEvent;
import org.eclipse.core.runtime.preferences.InstanceScope;
import org.eclipse.core.variables.IDynamicVariable;
import org.eclipse.core.variables.IStringVariable;
import org.eclipse.core.variables.IStringVariableManager;
import org.eclipse.core.variables.IValueVariable;
import org.eclipse.core.variables.IValueVariableListener;
import org.eclipse.core.variables.VariablesPlugin;
import org.eclipse.osgi.util.NLS;
import org.osgi.service.prefs.BackingStoreException;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.helpers.DefaultHandler;
/**
* Singleton string variable manager.
*/
public class StringVariableManager implements IStringVariableManager, IPreferenceChangeListener {
/**
* Dynamic variables - maps variable names to variables.
*/
private Map<String, IDynamicVariable> fDynamicVariables;
/**
* Value variables - maps variable names to variables.
*/
private Map<String, IStringVariable> fValueVariables;
/**
* Variable listeners
*/
private ListenerList<IValueVariableListener> fListeners;
// notifications
private static final int ADDED = 0;
private static final int CHANGED = 1;
private static final int REMOVED = 2;
/**
* Singleton variable manager.
*/
private static StringVariableManager fgManager;
// true during internal updates indicates that change notification
// should be suppressed/ignored.
private boolean fInternalChange = false;
// Variable extension point constants
private static final String ATTR_NAME= "name"; //$NON-NLS-1$
private static final String ATTR_DESCRIPTION="description"; //$NON-NLS-1$
private static final String ATTR_READ_ONLY="readOnly"; //$NON-NLS-1$
// Persisted variable XML constants
private static final String VALUE_VARIABLES_TAG= "valueVariables"; //$NON-NLS-1$
private static final String VALUE_VARIABLE_TAG= "valueVariable"; //$NON-NLS-1$
private static final String NAME_TAG= "name"; //$NON-NLS-1$
private static final String VALUE_TAG= "value"; //$NON-NLS-1$
private static final String DESCRIPTION_TAG="description"; //$NON-NLS-1$
private static final String READ_ONLY_TAG="readOnly"; //$NON-NLS-1$
// XML values
private static final String TRUE_VALUE= "true"; //$NON-NLS-1$
private static final String FALSE_VALUE= "false"; //$NON-NLS-1$
// preference store key for value variables
private static final String PREF_VALUE_VARIABLES= VariablesPlugin.getUniqueIdentifier() + ".valueVariables"; //$NON-NLS-1$
/**
* Notifies a string variable listener in a safe runnable to handle
* exceptions.
*/
class StringVariableNotifier implements ISafeRunnable {
private IValueVariableListener fListener;
private int fType;
private IValueVariable[] fVariables;
/**
* @see org.eclipse.core.runtime.ISafeRunnable#handleException(java.lang.Throwable)
*/
@Override
public void handleException(Throwable exception) {
IStatus status = new Status(IStatus.ERROR, VariablesPlugin.getUniqueIdentifier(), VariablesPlugin.INTERNAL_ERROR, "An exception occurred during string variable change notification", exception); //$NON-NLS-1$
VariablesPlugin.log(status);
}
/**
* @see org.eclipse.core.runtime.ISafeRunnable#run()
*/
@Override
public void run() throws Exception {
switch (fType) {
case ADDED:
fListener.variablesAdded(fVariables);
break;
case REMOVED:
fListener.variablesRemoved(fVariables);
break;
case CHANGED:
fListener.variablesChanged(fVariables);
break;
default:
break;
}
}
/**
* Notifies the given listener of the add/change/remove
*
* @param variables the {@link IValueVariable}s to notify about
* @param update the type of change
*/
public void notify(IValueVariable[] variables, int update) {
fVariables = variables;
fType = update;
for (IValueVariableListener iValueVariableListener : fListeners) {
fListener = iValueVariableListener;
SafeRunner.run(this);
}
fVariables = null;
fListener = null;
// persist variables whenever there is an add/change/remove
storeValueVariables();
}
}
/**
* Returns a new notifier.
*
* @return a new notifier
*/
private StringVariableNotifier getNotifier() {
return new StringVariableNotifier();
}
/**
* Returns the default string variable manager
*
* @return string variable manager
*/
public static StringVariableManager getDefault() {
if (fgManager == null) {
fgManager = new StringVariableManager();
}
return fgManager;
}
/**
* Constructs a new string variable manager.
*/
private StringVariableManager() {
fListeners = new ListenerList<>();
}
/**
* Load contributed variables and persisted variables
*/
private synchronized void initialize() {
if (fDynamicVariables == null) {
fInternalChange = true;
fDynamicVariables = new HashMap<>(5);
fValueVariables = new HashMap<>(5);
loadContributedValueVariables();
loadPersistedValueVariables();
loadDynamicVariables();
InstanceScope.INSTANCE.getNode(VariablesPlugin.PI_CORE_VARIABLES).addPreferenceChangeListener(this);
fInternalChange = false;
}
}
/**
* Loads contributed dynamic variables
*/
private void loadDynamicVariables() {
IExtensionPoint point = Platform.getExtensionRegistry().getExtensionPoint(VariablesPlugin.PI_CORE_VARIABLES, EXTENSION_POINT_DYNAMIC_VARIABLES);
IConfigurationElement elements[]= point.getConfigurationElements();
for (int i = 0; i < elements.length; i++) {
IConfigurationElement element = elements[i];
String name= element.getAttribute(ATTR_NAME);
if (name == null) {
VariablesPlugin.logMessage(NLS.bind("Variable extension missing required 'name' attribute: {0}", new String[] {element.getDeclaringExtension().getLabel()}), null); //$NON-NLS-1$
continue;
}
String description= element.getAttribute(ATTR_DESCRIPTION);
DynamicVariable variable= new DynamicVariable(name, description, element);
Object old = fDynamicVariables.put(variable.getName(), variable);
if (old != null) {
DynamicVariable oldVariable = (DynamicVariable)old;
VariablesPlugin.logMessage(NLS.bind("Dynamic variable extension from bundle ''{0}'' overrides existing extension variable ''{1}'' from bundle ''{2}''", //$NON-NLS-1$
new String[] {element.getDeclaringExtension().getContributor().getName(),oldVariable.getName(),
oldVariable.getConfigurationElement().getDeclaringExtension().getContributor().getName()}), null);
}
}
}
/**
* Loads contributed value variables. This is done before loading persisted values.
*/
private void loadContributedValueVariables() {
IExtensionPoint point = Platform.getExtensionRegistry().getExtensionPoint(VariablesPlugin.PI_CORE_VARIABLES, EXTENSION_POINT_VALUE_VARIABLES);
IConfigurationElement elements[]= point.getConfigurationElements();
for (int i = 0; i < elements.length; i++) {
IConfigurationElement element = elements[i];
String name= element.getAttribute(ATTR_NAME);
if (name == null) {
VariablesPlugin.logMessage(NLS.bind("Variable extension missing required 'name' attribute: {0}", new String[] {element.getDeclaringExtension().getLabel()}), null); //$NON-NLS-1$
continue;
}
String description= element.getAttribute(ATTR_DESCRIPTION);
boolean isReadOnly = TRUE_VALUE.equals(element.getAttribute(ATTR_READ_ONLY));
IValueVariable variable = new ContributedValueVariable(name, description, isReadOnly, element);
Object old = fValueVariables.put(name, variable);
if (old != null) {
StringVariable oldVariable = (StringVariable)old;
VariablesPlugin.logMessage(NLS.bind("Contributed variable extension from bundle ''{0}'' overrides existing extension variable ''{1}'' from bundle ''{2}''", //$NON-NLS-1$
new String[] {element.getDeclaringExtension().getContributor().getName(),oldVariable.getName(),
oldVariable.getConfigurationElement().getDeclaringExtension().getContributor().getName()}), null);
}
}
}
/**
* Loads persisted value variables from the preference store. This is done after
* loading value variables from the extension point. If a persisted variable has the
* same name as a extension contributed variable the variable's value will be set to
* the persisted value unless either a) The persisted value is <code>null</code>, or
* b) the variable is read-only.
*/
private void loadPersistedValueVariables() {
String variablesString = Platform.getPreferencesService().getString(VariablesPlugin.PI_CORE_VARIABLES, PREF_VALUE_VARIABLES, "", null); //$NON-NLS-1$
if (variablesString.length() == 0) {
return;
}
Element root= null;
try {
ByteArrayInputStream stream = new ByteArrayInputStream(variablesString.getBytes("UTF-8")); //$NON-NLS-1$
DocumentBuilder parser = DocumentBuilderFactory.newInstance().newDocumentBuilder();
parser.setErrorHandler(new DefaultHandler());
root = parser.parse(stream).getDocumentElement();
} catch (Exception e) {
VariablesPlugin.logMessage("An exception occurred while loading persisted value variables.", e); //$NON-NLS-1$
return;
}
if (!root.getNodeName().equals(VALUE_VARIABLES_TAG)) {
VariablesPlugin.logMessage("Invalid format encountered while loading persisted value variables.", null); //$NON-NLS-1$
return;
}
NodeList list= root.getChildNodes();
for (int i= 0, numItems= list.getLength(); i < numItems; i++) {
Node node= list.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE) {
Element element= (Element) node;
if (!element.getNodeName().equals(VALUE_VARIABLE_TAG)) {
VariablesPlugin.logMessage(NLS.bind("Invalid XML element encountered while loading value variables: {0}", new String[] {node.getNodeName()}), null); //$NON-NLS-1$
continue;
}
String name= element.getAttribute(NAME_TAG);
if (name.length() > 0) {
String value= element.getAttribute(VALUE_TAG);
String description= element.getAttribute(DESCRIPTION_TAG);
boolean readOnly= TRUE_VALUE.equals(element.getAttribute(READ_ONLY_TAG));
IValueVariable existing = getValueVariable(name);
if (existing == null){
ValueVariable variable = new ValueVariable(name, description, readOnly, value);
fValueVariables.put(name, variable);
} else if (!existing.isReadOnly() && value != null){
existing.setValue(value);
}
} else {
VariablesPlugin.logMessage("Invalid variable entry encountered while loading value variables. Variable name is null.", null); //$NON-NLS-1$
}
}
}
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#getVariables()
*/
@Override
public synchronized IStringVariable[] getVariables() {
initialize();
List<IStringVariable> list = new ArrayList<>(fDynamicVariables.size() + fValueVariables.size());
list.addAll(fDynamicVariables.values());
list.addAll(fValueVariables.values());
return list.toArray(new IStringVariable[list.size()]);
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#getValueVariables()
*/
@Override
public synchronized IValueVariable[] getValueVariables() {
initialize();
return fValueVariables.values().toArray(new IValueVariable[fValueVariables.size()]);
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#getDynamicVariables()
*/
@Override
public synchronized IDynamicVariable[] getDynamicVariables() {
initialize();
return fDynamicVariables.values().toArray(new IDynamicVariable[fDynamicVariables.size()]);
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#performStringSubstitution(java.lang.String)
*/
@Override
public String performStringSubstitution(String expression) throws CoreException {
return performStringSubstitution(expression, true);
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#newValueVariable(java.lang.String, java.lang.String)
*/
@Override
public IValueVariable newValueVariable(String name, String description) {
return newValueVariable(name, description, false, null);
}
/* (non-Javadoc)
* @see org.eclipse.core.variables.IStringVariableManager#newValueVariable(java.lang.String, java.lang.String, boolean, java.lang.String)
*/
@Override
public IValueVariable newValueVariable(String name, String description, boolean readOnly, String value) {
return new ValueVariable(name, description, readOnly, value);
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#addVariables(org.eclipse.debug.internal.core.stringsubstitution.IValueVariable[])
*/
@Override
public synchronized void addVariables(IValueVariable[] variables) throws CoreException {
initialize();
MultiStatus status = new MultiStatus(VariablesPlugin.getUniqueIdentifier(), VariablesPlugin.INTERNAL_ERROR, VariablesMessages.StringVariableManager_26, null);
for (int i = 0; i < variables.length; i++) {
IValueVariable variable = variables[i];
if (getValueVariable(variable.getName()) != null) {
status.add(new Status(IStatus.ERROR, VariablesPlugin.getUniqueIdentifier(), VariablesPlugin.INTERNAL_ERROR, NLS.bind(VariablesMessages.StringVariableManager_27, new String[]{variable.getName()}), null));
}
}
if (status.isOK()) {
for (int i = 0; i < variables.length; i++) {
IValueVariable variable = variables[i];
fValueVariables.put(variable.getName(), variable);
}
IValueVariable[] copy = new IValueVariable[variables.length];
System.arraycopy(variables, 0, copy, 0, variables.length);
getNotifier().notify(copy, ADDED);
return;
}
throw new CoreException(status);
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#removeVariables(org.eclipse.debug.internal.core.stringsubstitution.IValueVariable[])
*/
@Override
public synchronized void removeVariables(IValueVariable[] variables) {
initialize();
List<IValueVariable> removed = new ArrayList<>(variables.length);
for (int i = 0; i < variables.length; i++) {
IValueVariable variable = variables[i];
if (fValueVariables.remove(variable.getName()) != null) {
removed.add(variable);
}
}
if (removed.size() > 0) {
getNotifier().notify(removed.toArray(new IValueVariable[removed.size()]), REMOVED);
}
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#getDynamicVariable(java.lang.String)
*/
@Override
public synchronized IDynamicVariable getDynamicVariable(String name) {
initialize();
return fDynamicVariables.get(name);
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#getValueVariable(java.lang.String)
*/
@Override
public synchronized IValueVariable getValueVariable(String name) {
initialize();
return (IValueVariable) fValueVariables.get(name);
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#addValueVariableListener(org.eclipse.debug.internal.core.stringsubstitution.IValueVariableListener)
*/
@Override
public void addValueVariableListener(IValueVariableListener listener) {
fListeners.add(listener);
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#removeValueVariableListener(org.eclipse.debug.internal.core.stringsubstitution.IValueVariableListener)
*/
@Override
public void removeValueVariableListener(IValueVariableListener listener) {
fListeners.remove(listener);
}
/**
* Returns a memento representing the value variables currently registered.
*
* @return memento representing the value variables currently registered
* @throws IOException if an I/O exception occurs while creating the XML.
* @throws ParserConfigurationException if an I/O exception occurs while creating the XML.
* @throws TransformerException if an exception occurs while creating the XML.
*/
private String getValueVariablesAsXML() throws IOException, ParserConfigurationException, TransformerException {
IValueVariable[] variables = getValueVariables();
Document document= getDocument();
Element rootElement= document.createElement(VALUE_VARIABLES_TAG);
document.appendChild(rootElement);
for (int i = 0; i < variables.length; i++) {
IValueVariable variable = variables[i];
if (!variable.isReadOnly()){
// don't persist read-only variables or un-initialized contributed variables
if (!variable.isContributed() || ((ContributedValueVariable)variable).isInitialized()) {
Element element= document.createElement(VALUE_VARIABLE_TAG);
element.setAttribute(NAME_TAG, variable.getName());
String value= variable.getValue();
if (value != null) {
element.setAttribute(VALUE_TAG, value);
}
element.setAttribute(READ_ONLY_TAG, variable.isReadOnly() ? TRUE_VALUE : FALSE_VALUE);
String description= variable.getDescription();
if (description != null) {
element.setAttribute(DESCRIPTION_TAG, description);
}
rootElement.appendChild(element);
}
}
}
return serializeDocument(document);
}
private Document getDocument() throws ParserConfigurationException {
DocumentBuilderFactory dfactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = dfactory.newDocumentBuilder();
Document doc =docBuilder.newDocument();
return doc;
}
/**
* Serializes a XML document into a string - encoded in UTF8 format,
* with platform line separators.
*
* @param doc document to serialize
* @return the document as a string
* @throws TransformerException if an unrecoverable error occurs during the serialization
* @throws UnsupportedEncodingException if the encoding attempted to be used is not supported
*/
private String serializeDocument(Document doc) throws TransformerException, UnsupportedEncodingException {
ByteArrayOutputStream s= new ByteArrayOutputStream();
TransformerFactory factory= TransformerFactory.newInstance();
Transformer transformer= factory.newTransformer();
transformer.setOutputProperty(OutputKeys.METHOD, "xml"); //$NON-NLS-1$
transformer.setOutputProperty(OutputKeys.INDENT, "yes"); //$NON-NLS-1$
DOMSource source= new DOMSource(doc);
StreamResult outputTarget= new StreamResult(s);
transformer.transform(source, outputTarget);
return s.toString("UTF8"); //$NON-NLS-1$
}
/**
* Saves the value variables currently registered in the
* preference store.
*/
private synchronized void storeValueVariables() {
String variableString= ""; //$NON-NLS-1$
if (!fValueVariables.isEmpty()) {
try {
variableString= getValueVariablesAsXML();
} catch (IOException e) {
VariablesPlugin.log(new Status(IStatus.ERROR, VariablesPlugin.getUniqueIdentifier(), IStatus.ERROR, "An exception occurred while storing launch configuration variables.", e)); //$NON-NLS-1$
return;
} catch (ParserConfigurationException e) {
VariablesPlugin.log(new Status(IStatus.ERROR, VariablesPlugin.getUniqueIdentifier(), IStatus.ERROR, "An exception occurred while storing launch configuration variables.", e)); //$NON-NLS-1$
return;
} catch (TransformerException e) {
VariablesPlugin.log(new Status(IStatus.ERROR, VariablesPlugin.getUniqueIdentifier(), IStatus.ERROR, "An exception occurred while storing launch configuration variables.", e)); //$NON-NLS-1$
return;
}
}
fInternalChange = true;
try {
IEclipsePreferences prefs = InstanceScope.INSTANCE.getNode(VariablesPlugin.PI_CORE_VARIABLES);
prefs.put(PREF_VALUE_VARIABLES, variableString);
prefs.flush();
}
catch(BackingStoreException bse) {
VariablesPlugin.log(bse);
}
fInternalChange = false;
}
/**
* Fire a change notification for the given variable.
*
* @param variable the variable that has changed
*/
protected void notifyChanged(IValueVariable variable) {
if (!fInternalChange) {
IValueVariable existing = getValueVariable(variable.getName());
if (variable.equals(existing)) {
// do not do change notification for unregistered variables
getNotifier().notify(new IValueVariable[]{variable}, CHANGED);
}
}
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#generateVariableExpression(java.lang.String, java.lang.String)
*/
@Override
public String generateVariableExpression(String varName, String arg) {
StringBuffer buffer = new StringBuffer();
buffer.append("${"); //$NON-NLS-1$
buffer.append(varName);
if (arg != null) {
buffer.append(":"); //$NON-NLS-1$
buffer.append(arg);
}
buffer.append("}"); //$NON-NLS-1$
return buffer.toString();
}
/* (non-Javadoc)
* @see org.eclipse.debug.internal.core.stringsubstitution.IStringVariableManager#performStringSubstitution(java.lang.String, boolean)
*/
@Override
public String performStringSubstitution(String expression, boolean reportUndefinedVariables) throws CoreException {
return new StringSubstitutionEngine().performStringSubstitution(expression, reportUndefinedVariables, true, this);
}
/* (non-Javadoc)
* @see org.eclipse.core.variables.IStringVariableManager#validateStringVariables(java.lang.String)
*/
@Override
public void validateStringVariables(String expression) throws CoreException {
new StringSubstitutionEngine().validateStringVariables(expression, this);
}
/* (non-Javadoc)
* @see org.eclipse.core.variables.IStringVariableManager#getContributingPluginId(org.eclipse.core.variables.IStringVariable)
*/
@Override
public String getContributingPluginId(IStringVariable variable) {
if (variable instanceof StringVariable) {
return ((StringVariable) variable).getConfigurationElement().getContributor().getName();
}
return null;
}
/* (non-Javadoc)
* @see org.eclipse.core.runtime.preferences.IEclipsePreferences.IPreferenceChangeListener#preferenceChange(org.eclipse.core.runtime.preferences.IEclipsePreferences.PreferenceChangeEvent)
*/
@Override
public void preferenceChange(PreferenceChangeEvent event) {
if (PREF_VALUE_VARIABLES.equals(event.getKey())) {
synchronized (this) {
if (!fInternalChange) {
fValueVariables.clear();
loadPersistedValueVariables();
loadContributedValueVariables();
}
}
}
}
}