bundles/org.eclipse.core.runtime/src/org/eclipse/core/internal/content/ContentType.java - gerrit/platform/eclipse.platform.runtime - Git at Google

 /*******************************************************************************
  * Copyright (c) 2004 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Common Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/cpl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.core.internal.content;

 import java.io.*;
 import java.util.*;
 import org.eclipse.core.internal.runtime.InternalPlatform;
 import org.eclipse.core.internal.runtime.Policy;
 import org.eclipse.core.runtime.*;
 import org.eclipse.core.runtime.content.*;
 import org.osgi.service.prefs.BackingStoreException;
 import org.osgi.service.prefs.Preferences;

 public final class ContentType implements IContentType {

 	/* A placeholder for missing/invalid binary/text describers. */
 	private class InvalidDescriber implements IContentDescriber, ITextContentDescriber {
 		public int describe(InputStream contents, IContentDescription description) throws IOException {
 			return INVALID;
 		}

 		public int describe(Reader contents, IContentDescription description) throws IOException {
 			return INVALID;
 		}

 		public QualifiedName[] getSupportedOptions() {
 			return new QualifiedName[0];
 		}
 	}

 	final static byte ASSOCIATED_BY_EXTENSION = 2;
 	final static byte ASSOCIATED_BY_NAME = 1;
 	private static final String DESCRIBER_ELEMENT = "describer"; //$NON-NLS-1$
 	final static byte NOT_ASSOCIATED = 0;

 	public final static String PREF_DEFAULT_CHARSET = "charset"; //$NON-NLS-1$
 	public final static String PREF_FILE_EXTENSIONS = "file-extensions"; //$NON-NLS-1$
 	public final static String PREF_FILE_NAMES = "file-names"; //$NON-NLS-1$
 	final static byte PRIORITY_HIGH = 1;
 	final static byte PRIORITY_LOW = -1;
 	final static byte PRIORITY_NORMAL = 0;
 	final static int SPEC_PRE_DEFINED = IGNORE_PRE_DEFINED;
 	final static int SPEC_USER_DEFINED = IGNORE_USER_DEFINED;
 	final static byte STATUS_INVALID = 2;
 	final static byte STATUS_UNKNOWN = 3;
 	final static byte STATUS_VALID = 1;
 	private ContentType aliasTarget;
 	private String baseTypeId;
 	private IContentType[] children;
 	private IConfigurationElement contentTypeElement;
 	private String defaultCharset;
 	private String userCharset;
 	private IContentDescription defaultDescription;
 	private IContentDescriber describer;
 	private List fileSpecs;
 	private ContentTypeManager manager;
 	private String name;
 	private String namespace;
 	private byte priority;
 	private String simpleId;
 	private byte validation;

 	public static ContentType createContentType(ContentTypeManager manager, String namespace, String simpleId, String name, byte priority, String[] fileExtensions, String[] fileNames, String baseTypeId, String defaultCharset, IConfigurationElement contentTypeElement) {
 		ContentType contentType = new ContentType(manager);
 		contentType.defaultDescription = new DefaultDescription(contentType);
 		contentType.simpleId = simpleId;
 		contentType.namespace = namespace;
 		contentType.name = name;
 		contentType.priority = priority;
 		if ((fileExtensions != null && fileExtensions.length > 0) || (fileNames != null && fileNames.length > 0)) {
 			contentType.fileSpecs = new ArrayList(fileExtensions.length + fileNames.length);
 			for (int i = 0; i < fileNames.length; i++)
 				contentType.fileSpecs.add(createFileSpec(fileNames[i], FILE_NAME_SPEC | SPEC_PRE_DEFINED));
 			for (int i = 0; i < fileExtensions.length; i++)
 				contentType.fileSpecs.add(createFileSpec(fileExtensions[i], FILE_EXTENSION_SPEC | SPEC_PRE_DEFINED));
 		}
 		contentType.defaultCharset = defaultCharset;
 		contentType.contentTypeElement = contentTypeElement;
 		contentType.baseTypeId = baseTypeId;
 		contentType.processPreferences();
 		return contentType;
 	}

 	private void processPreferences() {
 		Preferences contentTypeNode = manager.getPreferences().node(getId());
 		// user set default charset
 		this.userCharset = contentTypeNode.get(PREF_DEFAULT_CHARSET, null);
 		// user set file names
 		String userSetFileNames = contentTypeNode.get(PREF_FILE_NAMES, null);
 		String[] fileNames = parseItems(userSetFileNames);
 		for (int i = 0; i < fileNames.length; i++)
 			internalAddFileSpec(fileNames[i], FILE_NAME_SPEC | SPEC_USER_DEFINED);
 		// user set file extensions
 		String userSetFileExtensions = contentTypeNode.get(PREF_FILE_EXTENSIONS, null);
 		String[] fileExtensions = parseItems(userSetFileExtensions);
 		for (int i = 0; i < fileExtensions.length; i++)
 			internalAddFileSpec(fileExtensions[i], FILE_EXTENSION_SPEC | SPEC_USER_DEFINED);
 	}

 	static FileSpec createFileSpec(String fileSpec, int type) {
 		return new FileSpec(fileSpec, type);
 	}

 	private static String getPreferenceKey(int flags) {
 		if ((flags & FILE_EXTENSION_SPEC) != 0)
 			return PREF_FILE_EXTENSIONS;
 		if ((flags & FILE_NAME_SPEC) != 0)
 			return PREF_FILE_NAMES;
 		throw new IllegalArgumentException("Unknown type: " + flags); //$NON-NLS-1$
 	}

 	static String[] parseItems(String string) {
 		if (string == null)
 			return new String[0];
 		StringTokenizer tokenizer = new StringTokenizer(string, ","); //$NON-NLS-1$
 		if (!tokenizer.hasMoreTokens())
 			return new String[0];
 		String first = tokenizer.nextToken();
 		if (!tokenizer.hasMoreTokens())
 			return new String[] {first};
 		ArrayList items = new ArrayList();
 		items.add(first);
 		do {
 			items.add(tokenizer.nextToken());
 		} while (tokenizer.hasMoreTokens());
 		return (String[]) items.toArray(new String[items.size()]);
 	}

 	static String toListString(List list) {
 		if (list.isEmpty())
 			return ""; //$NON-NLS-1$
 		StringBuffer result = new StringBuffer();
 		for (Iterator i = list.iterator(); i.hasNext();) {
 			result.append(i.next());
 			result.append(',');
 		}
 		// ignore last comma
 		return result.substring(0, result.length() - 1);
 	}

 	static String toListString(Object[] list) {
 		if (list.length == 0)
 			return ""; //$NON-NLS-1$
 		StringBuffer result = new StringBuffer();
 		for (int i = 0; i < list.length; i++) {
 			result.append(list[i]);
 			result.append(',');
 		}
 		// ignore last comma
 		return result.substring(0, result.length() - 1);
 	}

 	public ContentType(ContentTypeManager manager) {
 		this.manager = manager;
 	}

 	public synchronized void addFileSpec(String fileSpec, int type) throws CoreException {
 		if (aliasTarget != null) {
 			getTarget().addFileSpec(fileSpec, type);
 			return;
 		}
 		if (type != FILE_EXTENSION_SPEC && type != FILE_NAME_SPEC)
 			throw new IllegalArgumentException("Unknown type: " + type); //$NON-NLS-1$
 		if (!internalAddFileSpec(fileSpec, type | SPEC_USER_DEFINED))
 			// the entry was already there, nothing to do...
 			return;
 		// notify listeners
 		manager.fireContentTypeChangeEvent(this);
 		// update preferences
 		String key = getPreferenceKey(type);
 		Preferences contentTypeNode = manager.getPreferences().node(getId());
 		final String[] userSet = internalGetFileSpecs(type | IGNORE_PRE_DEFINED);
 		contentTypeNode.put(key, toListString(userSet));
 		// persist preferences
 		try {
 			contentTypeNode.flush();
 		} catch (BackingStoreException bse) {
 			String message = Policy.bind("content.errorSavingSettings", getId()); //$NON-NLS-1$
 			IStatus status = new Status(IStatus.ERROR, Platform.PI_RUNTIME, 0, message, bse);
 			throw new CoreException(status);
 		}
 	}

 	int describe(IContentDescriber selectedDescriber, InputStream contents, ContentDescription description) {
 		try {
 			return selectedDescriber.describe(contents, description);
 		} catch (IOException ioe) {
 			if (ContentTypeManager.DEBUGGING) {
 				String message = Policy.bind("content.errorReadingContents", getId()); //$NON-NLS-1$
 				log(message, ioe);
 			}
 			return IContentDescriber.INVALID;
 		} catch (RuntimeException re) {
 			// describer seems to be buggy. just disable it (logging the reason)
 			invalidateDescriber(re);
 			return IContentDescriber.INVALID;
 		} catch (Error e) {
 			// describer got some serious problem. disable it (logging the reason) and throw the error again
 			invalidateDescriber(e);
 			throw e;
 		} finally {
 			((LazyInputStream) contents).rewind();
 		}
 	}

 	int describe(ITextContentDescriber selectedDescriber, Reader contents, ContentDescription description) {
 		try {
 			return selectedDescriber.describe(contents, description);
 		} catch (IOException ioe) {
 			if (ContentTypeManager.DEBUGGING) {
 				String message = Policy.bind("content.errorReadingContents", getId()); //$NON-NLS-1$
 				log(message, ioe);
 			}
 			return IContentDescriber.INVALID;
 		} catch (RuntimeException re) {
 			// describer seems to be buggy. just disable it (logging the reason)
 			invalidateDescriber(re);
 			return IContentDescriber.INVALID;
 		} catch (Error e) {
 			// describer got some serious problem. disable it (logging the reason) and throw the error again
 			invalidateDescriber(e);
 			throw e;
 		} finally {
 			((LazyReader) contents).rewind();
 		}
 	}

 	public IContentType getBaseType() {
 		if (aliasTarget != null)
 			return getTarget().getBaseType();
 		if (baseTypeId == null)
 			return null;
 		ContentType originalBaseType = manager.internalGetContentType(baseTypeId);
 		return originalBaseType != null ? originalBaseType.getTarget() : null;
 	}

 	String getBaseTypeId() {
 		return baseTypeId;
 	}

 	IContentType[] getChildren() {
 		if (children == null)
 			children = manager.getChildren(this);
 		return children;
 	}

 	/**
 	 * @see IContentType
 	 */
 	public String getDefaultCharset() {
 		if (aliasTarget != null)
 			return getTarget().getDefaultCharset();
 		String currentCharset = userCharset != null ? userCharset : internalGetDefaultCharset();
 		// an empty string as charset means: no default charset
 		return "".equals(currentCharset) ? null : currentCharset; //$NON-NLS-1$
 	}

 	public IContentDescription getDefaultDescription() {
 		if (aliasTarget != null)
 			return getTarget().getDefaultDescription();
 		return defaultDescription;
 	}

 	public int getDepth() {
 		ContentType baseType = (ContentType) getBaseType();
 		if (baseType == null)
 			return 0;
 		return 1 + baseType.getDepth();
 	}

 	public IContentDescriber getDescriber() {
 		if (aliasTarget != null)
 			return getTarget().getDescriber();
 		// if "" is specified no describer should be created
 		if ("".equals(contentTypeElement.getAttributeAsIs(DESCRIBER_ELEMENT))) //$NON-NLS-1$
 			return null;
 		synchronized (this) {
 			if (describer != null)
 				return describer;
 			if (contentTypeElement.getChildren(DESCRIBER_ELEMENT).length > 0 || contentTypeElement.getAttributeAsIs(DESCRIBER_ELEMENT) != null)
 				try {
 					return describer = (IContentDescriber) contentTypeElement.createExecutableExtension(DESCRIBER_ELEMENT);
 				} catch (CoreException ce) {
 					// the content type definition was invalid. Ensure we don't
 					// try again, and this content type does not accept any
 					// contents
 					return invalidateDescriber(ce);
 				}
 		}
 		ContentType baseType = (ContentType) getBaseType();
 		return baseType == null ? null : baseType.getDescriber();
 	}

 	/**
 	 * @see IContentType
 	 */
 	public IContentDescription getDescriptionFor(InputStream contents, QualifiedName[] options) throws IOException {
 		InputStream buffer = ContentTypeManager.readBuffer(contents);
 		if (buffer == null)
 			return defaultDescription;
 		return internalGetDescriptionFor(buffer, options);
 	}

 	/**
 	 * @see IContentType
 	 */
 	public IContentDescription getDescriptionFor(Reader contents, QualifiedName[] options) throws IOException {
 		Reader buffer = ContentTypeManager.readBuffer(contents);
 		if (buffer == null)
 			return defaultDescription;
 		return internalGetDescriptionFor(buffer, options);
 	}

 	public String[] getFileSpecs(int typeMask) {
 		if (aliasTarget != null)
 			return getTarget().getFileSpecs(typeMask);
 		return internalGetFileSpecs(typeMask);
 	}

 	private String[] internalGetFileSpecs(int typeMask) {
 		if (fileSpecs == null)
 			return new String[0];
 		// invert the last two bits so it is easier to compare
 		typeMask ^= (IGNORE_PRE_DEFINED | IGNORE_USER_DEFINED);
 		List result = new ArrayList(fileSpecs.size());
 		for (Iterator i = fileSpecs.iterator(); i.hasNext();) {
 			FileSpec spec = (FileSpec) i.next();
 			if ((spec.getType() & typeMask) == spec.getType())
 				result.add(spec.getText());
 		}
 		return (String[]) result.toArray(new String[result.size()]);
 	}

 	public String getId() {
 		return namespace + '.' + simpleId;
 	}

 	public String getName() {
 		return name;
 	}

 	byte getPriority() {
 		return priority;
 	}

 	String getSimpleId() {
 		return simpleId;
 	}

 	/*
 	 * Returns the alias target, if one is found, or this object otherwise.
 	 */
 	ContentType getTarget() {
 		if (aliasTarget == null)
 			return this;
 		return aliasTarget.getTarget();
 	}

 	byte getValidation() {
 		return validation;
 	}

 	/**
 	 * @param text the file spec string
 	 * @param typeMask FILE_NAME_SPEC or FILE_EXTENSION_SPEC
 	 * @return true if this file spec has already been added, false otherwise
 	 */
 	private boolean hasFileSpec(String text, int typeMask) {
 		if (fileSpecs == null)
 			return false;
 		for (Iterator i = fileSpecs.iterator(); i.hasNext();) {
 			FileSpec spec = (FileSpec) i.next();
 			if (spec.equals(text, typeMask))
 				return true;
 		}
 		return false;
 	}

 	boolean internalAddFileSpec(String fileSpec, int typeMask) {
 		if (hasFileSpec(fileSpec, typeMask))
 			return false;
 		if (aliasTarget != null)
 			return aliasTarget.internalAddFileSpec(fileSpec, typeMask);
 		if (fileSpecs == null)
 			fileSpecs = new ArrayList(3);
 		fileSpecs.add(createFileSpec(fileSpec, typeMask));
 		return true;
 	}

 	private String internalGetDefaultCharset() {
 		if (defaultCharset == null) {
 			ContentType baseType = (ContentType) getBaseType();
 			return baseType == null ? null : baseType.getDefaultCharset();
 		}
 		return defaultCharset;
 	}

 	IContentDescription internalGetDescriptionFor(InputStream buffer, QualifiedName[] options) {
 		if (aliasTarget != null)
 			return getTarget().internalGetDescriptionFor(buffer, options);
 		if (buffer == null)
 			return defaultDescription;
 		IContentDescriber describer = this.getDescriber();
 		// no describer - just return the default description
 		if (describer == null)
 			return defaultDescription;
 		ContentDescription description = new ContentDescription(options);
 		describe(describer, buffer, description);
 		// if the describer didn't add any details, just return the default
 		// description
 		if (!description.isSet())
 			return defaultDescription;
 		// check if any of the defaults need to be applied
 		if (description.isRequested(IContentDescription.CHARSET) && description.getProperty(IContentDescription.CHARSET) == null)
 			description.setProperty(IContentDescription.CHARSET, getDefaultCharset());
 		description.setContentType(this);
 		return description;
 	}

 	IContentDescription internalGetDescriptionFor(Reader buffer, QualifiedName[] options) {
 		if (aliasTarget != null)
 			return getTarget().internalGetDescriptionFor(buffer, options);
 		if (buffer == null)
 			return defaultDescription;
 		IContentDescriber describer = this.getDescriber();
 		// no describer - just return the default description
 		if (describer == null)
 			return defaultDescription;
 		ContentDescription description = new ContentDescription(options);
 		if (!(describer instanceof ITextContentDescriber))
 			throw new UnsupportedOperationException();
 		describe((ITextContentDescriber) describer, buffer, description);
 		// if the describer didn't add any details, just return the default description
 		if (!description.isSet())
 			return defaultDescription;
 		// check if any of the defaults need to be applied
 		if (description.isRequested(IContentDescription.CHARSET) && description.getProperty(IContentDescription.CHARSET) == null)
 			description.setProperty(IContentDescription.CHARSET, getDefaultCharset());
 		description.setContentType(this);
 		return description;
 	}

 	public byte internalIsAssociatedWith(String fileName) {
 		if (aliasTarget != null)
 			return getTarget().internalIsAssociatedWith(fileName);
 		if (hasFileSpec(fileName, FILE_NAME_SPEC))
 			return ASSOCIATED_BY_NAME;
 		String fileExtension = ContentTypeManager.getFileExtension(fileName);
 		if (hasFileSpec(fileExtension, FILE_EXTENSION_SPEC))
 			return ASSOCIATED_BY_EXTENSION;
 		// if does not have *built-in* file specs, delegate to parent (if any)
 		if (!hasAnyFileSpec(SPEC_PRE_DEFINED)) {
 			IContentType baseType = getBaseType();
 			if (baseType != null)
 				return ((ContentType) baseType).internalIsAssociatedWith(fileName);
 		}
 		return NOT_ASSOCIATED;
 	}

 	private boolean hasAnyFileSpec(int typeMask) {
 		if (fileSpecs == null || fileSpecs.isEmpty())
 			return false;
 		for (Iterator i = fileSpecs.iterator(); i.hasNext();) {
 			FileSpec spec = (FileSpec) i.next();
 			if ((spec.getType() & typeMask) == typeMask)
 				return true;
 		}
 		return false;
 	}

 	boolean internalRemoveFileSpec(String fileSpec, int typeMask) {
 		if (aliasTarget != null)
 			return aliasTarget.internalRemoveFileSpec(fileSpec, typeMask);
 		if (fileSpecs == null)
 			return false;
 		for (Iterator i = fileSpecs.iterator(); i.hasNext();) {
 			FileSpec spec = (FileSpec) i.next();
 			if ((spec.getType() == typeMask) && fileSpec.equals(spec.getText())) {
 				i.remove();
 				return true;
 			}
 		}
 		return false;
 	}

 	private IContentDescriber invalidateDescriber(Throwable reason) {
 		setValidation(STATUS_INVALID);
 		String message = Policy.bind("content.invalidContentDescriber", getId()); //$NON-NLS-1$
 		log(message, reason);
 		return describer = new InvalidDescriber();
 	}

 	public boolean isAssociatedWith(String fileName) {
 		return internalIsAssociatedWith(fileName) != NOT_ASSOCIATED;
 	}

 	public boolean isKindOf(IContentType another) {
 		if (another == null)
 			return false;
 		if (aliasTarget != null)
 			return getTarget().isKindOf(another);
 		if (this == another)
 			return true;
 		if (getDepth() <= ((ContentType) another).getDepth())
 			return false;
 		IContentType baseType = getBaseType();
 		return baseType != null && baseType.isKindOf(another);
 	}

 	public boolean isText() {
 		return isKindOf(manager.getContentType(IContentTypeManager.CT_TEXT));
 	}

 	boolean isValid() {
 		return validation == STATUS_VALID;
 	}

 	private void log(String message, Throwable reason) {
 		// don't log CoreExceptions again
 		IStatus status = new Status(IStatus.ERROR, Platform.PI_RUNTIME, 0, message, reason instanceof CoreException ? null : reason);
 		InternalPlatform.getDefault().log(status);
 	}

 	public synchronized void removeFileSpec(String fileSpec, int type) throws CoreException {
 		if (aliasTarget != null) {
 			getTarget().removeFileSpec(fileSpec, type);
 			return;
 		}
 		if (type != FILE_EXTENSION_SPEC && type != FILE_NAME_SPEC)
 			throw new IllegalArgumentException("Unknown type: " + type); //$NON-NLS-1$
 		if (!internalRemoveFileSpec(fileSpec, type | SPEC_USER_DEFINED))
 			// the entry was not there... nothing to do
 			return;
 		// notify listeners
 		manager.fireContentTypeChangeEvent(this);
 		// update preferences
 		String key = getPreferenceKey(type);
 		Preferences contentTypeNode = manager.getPreferences().node(getId());
 		final String[] userSet = internalGetFileSpecs(type | IGNORE_PRE_DEFINED);
 		if (userSet.length == 0)
 			contentTypeNode.remove(key);
 		else
 			contentTypeNode.put(key, toListString(userSet));
 		// persist using preferences
 		try {
 			contentTypeNode.flush();
 		} catch (BackingStoreException bse) {
 			String message = Policy.bind("content.errorSavingSettings", getId()); //$NON-NLS-1$
 			IStatus status = new Status(IStatus.ERROR, Platform.PI_RUNTIME, 0, message, bse);
 			throw new CoreException(status);
 		}
 	}

 	void setAliasTarget(ContentType newTarget) {
 		// when changing the target, it must be cleared first
 		if (aliasTarget != null && newTarget != null)
 			return;
 		// don't allow a sub-type to be made into an alias to the base type
 		if (aliasTarget == null && isKindOf(newTarget))
 			return;
 		if (ContentTypeManager.DEBUGGING)
 			Policy.debug("Setting alias target for " + this + " -> " + newTarget); //$NON-NLS-1$ //$NON-NLS-2$
 		aliasTarget = newTarget;
 	}

 	/*
 	 * (non-Javadoc)
 	 * @see org.eclipse.core.runtime.content.IContentType#setDefaultCharset(java.lang.String)
 	 */
 	public void setDefaultCharset(String newCharset) throws CoreException {
 		if (userCharset == null) {
 			if (newCharset == null)
 				return;
 		} else if (userCharset.equals(newCharset))
 			return;
 		userCharset = newCharset;
 		// notify listeners
 		manager.fireContentTypeChangeEvent(this);
 		// update preferences
 		Preferences contentTypeNode = manager.getPreferences().node(getId());
 		if (userCharset == null)
 			contentTypeNode.remove(PREF_DEFAULT_CHARSET);
 		else
 			contentTypeNode.put(PREF_DEFAULT_CHARSET, userCharset);
 		// persist preferences
 		try {
 			contentTypeNode.flush();
 		} catch (BackingStoreException bse) {
 			String message = Policy.bind("content.errorSavingSettings", getId()); //$NON-NLS-1$
 			IStatus status = new Status(IStatus.ERROR, Platform.PI_RUNTIME, 0, message, bse);
 			throw new CoreException(status);
 		}
 	}

 	void setValidation(byte validation) {
 		this.validation = validation;
 		if (ContentTypeManager.DEBUGGING)
 			Policy.debug("Validating " + this + ": " + getValidationString(validation)); //$NON-NLS-1$ //$NON-NLS-2$
 	}

 	private static String getValidationString(byte validation) {
 		return validation == STATUS_VALID ? "VALID" : (validation == STATUS_INVALID ? "INVALID" : "UNKNOWN"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
 	}

 	public String toString() {
 		return getId();
 	}

 	public boolean isAlias() {
 		return aliasTarget != null;
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2004 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Common Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/cpl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.core.internal.content;

	import java.io.*;
	import java.util.*;
	import org.eclipse.core.internal.runtime.InternalPlatform;
	import org.eclipse.core.internal.runtime.Policy;
	import org.eclipse.core.runtime.*;
	import org.eclipse.core.runtime.content.*;
	import org.osgi.service.prefs.BackingStoreException;
	import org.osgi.service.prefs.Preferences;

	public final class ContentType implements IContentType {

	/* A placeholder for missing/invalid binary/text describers. */
	private class InvalidDescriber implements IContentDescriber, ITextContentDescriber {
	public int describe(InputStream contents, IContentDescription description) throws IOException {
	return INVALID;
	}

	public int describe(Reader contents, IContentDescription description) throws IOException {
	return INVALID;
	}

	public QualifiedName[] getSupportedOptions() {
	return new QualifiedName[0];
	}
	}

	final static byte ASSOCIATED_BY_EXTENSION = 2;
	final static byte ASSOCIATED_BY_NAME = 1;
	private static final String DESCRIBER_ELEMENT = "describer"; //$NON-NLS-1$
	final static byte NOT_ASSOCIATED = 0;

	public final static String PREF_DEFAULT_CHARSET = "charset"; //$NON-NLS-1$
	public final static String PREF_FILE_EXTENSIONS = "file-extensions"; //$NON-NLS-1$
	public final static String PREF_FILE_NAMES = "file-names"; //$NON-NLS-1$
	final static byte PRIORITY_HIGH = 1;
	final static byte PRIORITY_LOW = -1;
	final static byte PRIORITY_NORMAL = 0;
	final static int SPEC_PRE_DEFINED = IGNORE_PRE_DEFINED;
	final static int SPEC_USER_DEFINED = IGNORE_USER_DEFINED;
	final static byte STATUS_INVALID = 2;
	final static byte STATUS_UNKNOWN = 3;
	final static byte STATUS_VALID = 1;
	private ContentType aliasTarget;
	private String baseTypeId;
	private IContentType[] children;
	private IConfigurationElement contentTypeElement;
	private String defaultCharset;
	private String userCharset;
	private IContentDescription defaultDescription;
	private IContentDescriber describer;
	private List fileSpecs;
	private ContentTypeManager manager;
	private String name;
	private String namespace;
	private byte priority;
	private String simpleId;
	private byte validation;

	public static ContentType createContentType(ContentTypeManager manager, String namespace, String simpleId, String name, byte priority, String[] fileExtensions, String[] fileNames, String baseTypeId, String defaultCharset, IConfigurationElement contentTypeElement) {
	ContentType contentType = new ContentType(manager);
	contentType.defaultDescription = new DefaultDescription(contentType);
	contentType.simpleId = simpleId;
	contentType.namespace = namespace;
	contentType.name = name;
	contentType.priority = priority;
	if ((fileExtensions != null && fileExtensions.length > 0) \|\| (fileNames != null && fileNames.length > 0)) {
	contentType.fileSpecs = new ArrayList(fileExtensions.length + fileNames.length);
	for (int i = 0; i < fileNames.length; i++)
	contentType.fileSpecs.add(createFileSpec(fileNames[i], FILE_NAME_SPEC \| SPEC_PRE_DEFINED));
	for (int i = 0; i < fileExtensions.length; i++)
	contentType.fileSpecs.add(createFileSpec(fileExtensions[i], FILE_EXTENSION_SPEC \| SPEC_PRE_DEFINED));
	}
	contentType.defaultCharset = defaultCharset;
	contentType.contentTypeElement = contentTypeElement;
	contentType.baseTypeId = baseTypeId;
	contentType.processPreferences();
	return contentType;
	}

	private void processPreferences() {
	Preferences contentTypeNode = manager.getPreferences().node(getId());
	// user set default charset
	this.userCharset = contentTypeNode.get(PREF_DEFAULT_CHARSET, null);
	// user set file names
	String userSetFileNames = contentTypeNode.get(PREF_FILE_NAMES, null);
	String[] fileNames = parseItems(userSetFileNames);
	for (int i = 0; i < fileNames.length; i++)
	internalAddFileSpec(fileNames[i], FILE_NAME_SPEC \| SPEC_USER_DEFINED);
	// user set file extensions
	String userSetFileExtensions = contentTypeNode.get(PREF_FILE_EXTENSIONS, null);
	String[] fileExtensions = parseItems(userSetFileExtensions);
	for (int i = 0; i < fileExtensions.length; i++)
	internalAddFileSpec(fileExtensions[i], FILE_EXTENSION_SPEC \| SPEC_USER_DEFINED);
	}

	static FileSpec createFileSpec(String fileSpec, int type) {
	return new FileSpec(fileSpec, type);
	}

	private static String getPreferenceKey(int flags) {
	if ((flags & FILE_EXTENSION_SPEC) != 0)
	return PREF_FILE_EXTENSIONS;
	if ((flags & FILE_NAME_SPEC) != 0)
	return PREF_FILE_NAMES;
	throw new IllegalArgumentException("Unknown type: " + flags); //$NON-NLS-1$
	}

	static String[] parseItems(String string) {
	if (string == null)
	return new String[0];
	StringTokenizer tokenizer = new StringTokenizer(string, ","); //$NON-NLS-1$
	if (!tokenizer.hasMoreTokens())
	return new String[0];
	String first = tokenizer.nextToken();
	if (!tokenizer.hasMoreTokens())
	return new String[] {first};
	ArrayList items = new ArrayList();
	items.add(first);
	do {
	items.add(tokenizer.nextToken());
	} while (tokenizer.hasMoreTokens());
	return (String[]) items.toArray(new String[items.size()]);
	}

	static String toListString(List list) {
	if (list.isEmpty())
	return ""; //$NON-NLS-1$
	StringBuffer result = new StringBuffer();
	for (Iterator i = list.iterator(); i.hasNext();) {
	result.append(i.next());
	result.append(',');
	}
	// ignore last comma
	return result.substring(0, result.length() - 1);
	}

	static String toListString(Object[] list) {
	if (list.length == 0)
	return ""; //$NON-NLS-1$
	StringBuffer result = new StringBuffer();
	for (int i = 0; i < list.length; i++) {
	result.append(list[i]);
	result.append(',');
	}
	// ignore last comma
	return result.substring(0, result.length() - 1);
	}

	public ContentType(ContentTypeManager manager) {
	this.manager = manager;
	}

	public synchronized void addFileSpec(String fileSpec, int type) throws CoreException {
	if (aliasTarget != null) {
	getTarget().addFileSpec(fileSpec, type);
	return;
	}
	if (type != FILE_EXTENSION_SPEC && type != FILE_NAME_SPEC)
	throw new IllegalArgumentException("Unknown type: " + type); //$NON-NLS-1$
	if (!internalAddFileSpec(fileSpec, type \| SPEC_USER_DEFINED))
	// the entry was already there, nothing to do...
	return;
	// notify listeners
	manager.fireContentTypeChangeEvent(this);
	// update preferences
	String key = getPreferenceKey(type);
	Preferences contentTypeNode = manager.getPreferences().node(getId());
	final String[] userSet = internalGetFileSpecs(type \| IGNORE_PRE_DEFINED);
	contentTypeNode.put(key, toListString(userSet));
	// persist preferences
	try {
	contentTypeNode.flush();
	} catch (BackingStoreException bse) {
	String message = Policy.bind("content.errorSavingSettings", getId()); //$NON-NLS-1$
	IStatus status = new Status(IStatus.ERROR, Platform.PI_RUNTIME, 0, message, bse);
	throw new CoreException(status);
	}
	}

	int describe(IContentDescriber selectedDescriber, InputStream contents, ContentDescription description) {
	try {
	return selectedDescriber.describe(contents, description);
	} catch (IOException ioe) {
	if (ContentTypeManager.DEBUGGING) {
	String message = Policy.bind("content.errorReadingContents", getId()); //$NON-NLS-1$
	log(message, ioe);
	}
	return IContentDescriber.INVALID;
	} catch (RuntimeException re) {
	// describer seems to be buggy. just disable it (logging the reason)
	invalidateDescriber(re);
	return IContentDescriber.INVALID;
	} catch (Error e) {
	// describer got some serious problem. disable it (logging the reason) and throw the error again
	invalidateDescriber(e);
	throw e;
	} finally {
	((LazyInputStream) contents).rewind();
	}
	}

	int describe(ITextContentDescriber selectedDescriber, Reader contents, ContentDescription description) {
	try {
	return selectedDescriber.describe(contents, description);
	} catch (IOException ioe) {
	if (ContentTypeManager.DEBUGGING) {
	String message = Policy.bind("content.errorReadingContents", getId()); //$NON-NLS-1$
	log(message, ioe);
	}
	return IContentDescriber.INVALID;
	} catch (RuntimeException re) {
	// describer seems to be buggy. just disable it (logging the reason)
	invalidateDescriber(re);
	return IContentDescriber.INVALID;
	} catch (Error e) {
	// describer got some serious problem. disable it (logging the reason) and throw the error again
	invalidateDescriber(e);
	throw e;
	} finally {
	((LazyReader) contents).rewind();
	}
	}

	public IContentType getBaseType() {
	if (aliasTarget != null)
	return getTarget().getBaseType();
	if (baseTypeId == null)
	return null;
	ContentType originalBaseType = manager.internalGetContentType(baseTypeId);
	return originalBaseType != null ? originalBaseType.getTarget() : null;
	}

	String getBaseTypeId() {
	return baseTypeId;
	}

	IContentType[] getChildren() {
	if (children == null)
	children = manager.getChildren(this);
	return children;
	}

	/**
	* @see IContentType
	*/
	public String getDefaultCharset() {
	if (aliasTarget != null)
	return getTarget().getDefaultCharset();
	String currentCharset = userCharset != null ? userCharset : internalGetDefaultCharset();
	// an empty string as charset means: no default charset
	return "".equals(currentCharset) ? null : currentCharset; //$NON-NLS-1$
	}

	public IContentDescription getDefaultDescription() {
	if (aliasTarget != null)
	return getTarget().getDefaultDescription();
	return defaultDescription;
	}

	public int getDepth() {
	ContentType baseType = (ContentType) getBaseType();
	if (baseType == null)
	return 0;
	return 1 + baseType.getDepth();
	}

	public IContentDescriber getDescriber() {
	if (aliasTarget != null)
	return getTarget().getDescriber();
	// if "" is specified no describer should be created
	if ("".equals(contentTypeElement.getAttributeAsIs(DESCRIBER_ELEMENT))) //$NON-NLS-1$
	return null;
	synchronized (this) {
	if (describer != null)
	return describer;
	if (contentTypeElement.getChildren(DESCRIBER_ELEMENT).length > 0 \|\| contentTypeElement.getAttributeAsIs(DESCRIBER_ELEMENT) != null)
	try {
	return describer = (IContentDescriber) contentTypeElement.createExecutableExtension(DESCRIBER_ELEMENT);
	} catch (CoreException ce) {
	// the content type definition was invalid. Ensure we don't
	// try again, and this content type does not accept any
	// contents
	return invalidateDescriber(ce);
	}
	}
	ContentType baseType = (ContentType) getBaseType();
	return baseType == null ? null : baseType.getDescriber();
	}

	/**
	* @see IContentType
	*/
	public IContentDescription getDescriptionFor(InputStream contents, QualifiedName[] options) throws IOException {
	InputStream buffer = ContentTypeManager.readBuffer(contents);
	if (buffer == null)
	return defaultDescription;
	return internalGetDescriptionFor(buffer, options);
	}

	/**
	* @see IContentType
	*/
	public IContentDescription getDescriptionFor(Reader contents, QualifiedName[] options) throws IOException {
	Reader buffer = ContentTypeManager.readBuffer(contents);
	if (buffer == null)
	return defaultDescription;
	return internalGetDescriptionFor(buffer, options);
	}

	public String[] getFileSpecs(int typeMask) {
	if (aliasTarget != null)
	return getTarget().getFileSpecs(typeMask);
	return internalGetFileSpecs(typeMask);
	}

	private String[] internalGetFileSpecs(int typeMask) {
	if (fileSpecs == null)
	return new String[0];
	// invert the last two bits so it is easier to compare
	typeMask ^= (IGNORE_PRE_DEFINED \| IGNORE_USER_DEFINED);
	List result = new ArrayList(fileSpecs.size());
	for (Iterator i = fileSpecs.iterator(); i.hasNext();) {
	FileSpec spec = (FileSpec) i.next();
	if ((spec.getType() & typeMask) == spec.getType())
	result.add(spec.getText());
	}
	return (String[]) result.toArray(new String[result.size()]);
	}

	public String getId() {
	return namespace + '.' + simpleId;
	}

	public String getName() {
	return name;
	}

	byte getPriority() {
	return priority;
	}

	String getSimpleId() {
	return simpleId;
	}

	/*
	* Returns the alias target, if one is found, or this object otherwise.
	*/
	ContentType getTarget() {
	if (aliasTarget == null)
	return this;
	return aliasTarget.getTarget();
	}

	byte getValidation() {
	return validation;
	}

	/**
	* @param text the file spec string
	* @param typeMask FILE_NAME_SPEC or FILE_EXTENSION_SPEC
	* @return true if this file spec has already been added, false otherwise
	*/
	private boolean hasFileSpec(String text, int typeMask) {
	if (fileSpecs == null)
	return false;
	for (Iterator i = fileSpecs.iterator(); i.hasNext();) {
	FileSpec spec = (FileSpec) i.next();
	if (spec.equals(text, typeMask))
	return true;
	}
	return false;
	}

	boolean internalAddFileSpec(String fileSpec, int typeMask) {
	if (hasFileSpec(fileSpec, typeMask))
	return false;
	if (aliasTarget != null)
	return aliasTarget.internalAddFileSpec(fileSpec, typeMask);
	if (fileSpecs == null)
	fileSpecs = new ArrayList(3);
	fileSpecs.add(createFileSpec(fileSpec, typeMask));
	return true;
	}

	private String internalGetDefaultCharset() {
	if (defaultCharset == null) {
	ContentType baseType = (ContentType) getBaseType();
	return baseType == null ? null : baseType.getDefaultCharset();
	}
	return defaultCharset;
	}

	IContentDescription internalGetDescriptionFor(InputStream buffer, QualifiedName[] options) {
	if (aliasTarget != null)
	return getTarget().internalGetDescriptionFor(buffer, options);
	if (buffer == null)
	return defaultDescription;
	IContentDescriber describer = this.getDescriber();
	// no describer - just return the default description
	if (describer == null)
	return defaultDescription;
	ContentDescription description = new ContentDescription(options);
	describe(describer, buffer, description);
	// if the describer didn't add any details, just return the default
	// description
	if (!description.isSet())
	return defaultDescription;
	// check if any of the defaults need to be applied
	if (description.isRequested(IContentDescription.CHARSET) && description.getProperty(IContentDescription.CHARSET) == null)
	description.setProperty(IContentDescription.CHARSET, getDefaultCharset());
	description.setContentType(this);
	return description;
	}

	IContentDescription internalGetDescriptionFor(Reader buffer, QualifiedName[] options) {
	if (aliasTarget != null)
	return getTarget().internalGetDescriptionFor(buffer, options);
	if (buffer == null)
	return defaultDescription;
	IContentDescriber describer = this.getDescriber();
	// no describer - just return the default description
	if (describer == null)
	return defaultDescription;
	ContentDescription description = new ContentDescription(options);
	if (!(describer instanceof ITextContentDescriber))
	throw new UnsupportedOperationException();
	describe((ITextContentDescriber) describer, buffer, description);
	// if the describer didn't add any details, just return the default description
	if (!description.isSet())
	return defaultDescription;
	// check if any of the defaults need to be applied
	if (description.isRequested(IContentDescription.CHARSET) && description.getProperty(IContentDescription.CHARSET) == null)
	description.setProperty(IContentDescription.CHARSET, getDefaultCharset());
	description.setContentType(this);
	return description;
	}

	public byte internalIsAssociatedWith(String fileName) {
	if (aliasTarget != null)
	return getTarget().internalIsAssociatedWith(fileName);
	if (hasFileSpec(fileName, FILE_NAME_SPEC))
	return ASSOCIATED_BY_NAME;
	String fileExtension = ContentTypeManager.getFileExtension(fileName);
	if (hasFileSpec(fileExtension, FILE_EXTENSION_SPEC))
	return ASSOCIATED_BY_EXTENSION;
	// if does not have built-in file specs, delegate to parent (if any)
	if (!hasAnyFileSpec(SPEC_PRE_DEFINED)) {
	IContentType baseType = getBaseType();
	if (baseType != null)
	return ((ContentType) baseType).internalIsAssociatedWith(fileName);
	}
	return NOT_ASSOCIATED;
	}

	private boolean hasAnyFileSpec(int typeMask) {
	if (fileSpecs == null \|\| fileSpecs.isEmpty())
	return false;
	for (Iterator i = fileSpecs.iterator(); i.hasNext();) {
	FileSpec spec = (FileSpec) i.next();
	if ((spec.getType() & typeMask) == typeMask)
	return true;
	}
	return false;
	}

	boolean internalRemoveFileSpec(String fileSpec, int typeMask) {
	if (aliasTarget != null)
	return aliasTarget.internalRemoveFileSpec(fileSpec, typeMask);
	if (fileSpecs == null)
	return false;
	for (Iterator i = fileSpecs.iterator(); i.hasNext();) {
	FileSpec spec = (FileSpec) i.next();
	if ((spec.getType() == typeMask) && fileSpec.equals(spec.getText())) {
	i.remove();
	return true;
	}
	}
	return false;
	}

	private IContentDescriber invalidateDescriber(Throwable reason) {
	setValidation(STATUS_INVALID);
	String message = Policy.bind("content.invalidContentDescriber", getId()); //$NON-NLS-1$
	log(message, reason);
	return describer = new InvalidDescriber();
	}

	public boolean isAssociatedWith(String fileName) {
	return internalIsAssociatedWith(fileName) != NOT_ASSOCIATED;
	}

	public boolean isKindOf(IContentType another) {
	if (another == null)
	return false;
	if (aliasTarget != null)
	return getTarget().isKindOf(another);
	if (this == another)
	return true;
	if (getDepth() <= ((ContentType) another).getDepth())
	return false;
	IContentType baseType = getBaseType();
	return baseType != null && baseType.isKindOf(another);
	}

	public boolean isText() {
	return isKindOf(manager.getContentType(IContentTypeManager.CT_TEXT));
	}

	boolean isValid() {
	return validation == STATUS_VALID;
	}

	private void log(String message, Throwable reason) {
	// don't log CoreExceptions again
	IStatus status = new Status(IStatus.ERROR, Platform.PI_RUNTIME, 0, message, reason instanceof CoreException ? null : reason);
	InternalPlatform.getDefault().log(status);
	}

	public synchronized void removeFileSpec(String fileSpec, int type) throws CoreException {
	if (aliasTarget != null) {
	getTarget().removeFileSpec(fileSpec, type);
	return;
	}
	if (type != FILE_EXTENSION_SPEC && type != FILE_NAME_SPEC)
	throw new IllegalArgumentException("Unknown type: " + type); //$NON-NLS-1$
	if (!internalRemoveFileSpec(fileSpec, type \| SPEC_USER_DEFINED))
	// the entry was not there... nothing to do
	return;
	// notify listeners
	manager.fireContentTypeChangeEvent(this);
	// update preferences
	String key = getPreferenceKey(type);
	Preferences contentTypeNode = manager.getPreferences().node(getId());
	final String[] userSet = internalGetFileSpecs(type \| IGNORE_PRE_DEFINED);
	if (userSet.length == 0)
	contentTypeNode.remove(key);
	else
	contentTypeNode.put(key, toListString(userSet));
	// persist using preferences
	try {
	contentTypeNode.flush();
	} catch (BackingStoreException bse) {
	String message = Policy.bind("content.errorSavingSettings", getId()); //$NON-NLS-1$
	IStatus status = new Status(IStatus.ERROR, Platform.PI_RUNTIME, 0, message, bse);
	throw new CoreException(status);
	}
	}

	void setAliasTarget(ContentType newTarget) {
	// when changing the target, it must be cleared first
	if (aliasTarget != null && newTarget != null)
	return;
	// don't allow a sub-type to be made into an alias to the base type
	if (aliasTarget == null && isKindOf(newTarget))
	return;
	if (ContentTypeManager.DEBUGGING)
	Policy.debug("Setting alias target for " + this + " -> " + newTarget); //$NON-NLS-1$ //$NON-NLS-2$
	aliasTarget = newTarget;
	}

	/*
	* (non-Javadoc)
	* @see org.eclipse.core.runtime.content.IContentType#setDefaultCharset(java.lang.String)
	*/
	public void setDefaultCharset(String newCharset) throws CoreException {
	if (userCharset == null) {
	if (newCharset == null)
	return;
	} else if (userCharset.equals(newCharset))
	return;
	userCharset = newCharset;
	// notify listeners
	manager.fireContentTypeChangeEvent(this);
	// update preferences
	Preferences contentTypeNode = manager.getPreferences().node(getId());
	if (userCharset == null)
	contentTypeNode.remove(PREF_DEFAULT_CHARSET);
	else
	contentTypeNode.put(PREF_DEFAULT_CHARSET, userCharset);
	// persist preferences
	try {
	contentTypeNode.flush();
	} catch (BackingStoreException bse) {
	String message = Policy.bind("content.errorSavingSettings", getId()); //$NON-NLS-1$
	IStatus status = new Status(IStatus.ERROR, Platform.PI_RUNTIME, 0, message, bse);
	throw new CoreException(status);
	}
	}

	void setValidation(byte validation) {
	this.validation = validation;
	if (ContentTypeManager.DEBUGGING)
	Policy.debug("Validating " + this + ": " + getValidationString(validation)); //$NON-NLS-1$ //$NON-NLS-2$
	}

	private static String getValidationString(byte validation) {
	return validation == STATUS_VALID ? "VALID" : (validation == STATUS_INVALID ? "INVALID" : "UNKNOWN"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
	}

	public String toString() {
	return getId();
	}

	public boolean isAlias() {
	return aliasTarget != null;
	}
	}