Bug 119327 [Model Sync] Add IStorageMerger

1 files changed, 200 insertions, 0 deletions

diff --git a/bundles/org.eclipse.team.core/src/org/eclipse/team/internal/core/mapping/DelegatingStorageMerger.java b/bundles/org.eclipse.team.core/src/org/eclipse/team/internal/core/mapping/DelegatingStorageMerger.java
new file mode 100644
index 000000000..19c07f953
--- /dev/null
+++ b/bundles/org.eclipse.team.core/src/org/eclipse/team/internal/core/mapping/DelegatingStorageMerger.java
@@ -0,0 +1,200 @@
+/*******************************************************************************
+ * Copyright (c) 2006 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.team.internal.core.mapping;
+
+import java.io.IOException;
+import java.io.OutputStream;
+
+import org.eclipse.core.resources.IFile;
+import org.eclipse.core.resources.IStorage;
+import org.eclipse.core.runtime.*;
+import org.eclipse.core.runtime.content.*;
+import org.eclipse.osgi.util.NLS;
+import org.eclipse.team.core.Team;
+import org.eclipse.team.core.TeamException;
+import org.eclipse.team.core.diff.IThreeWayDiff;
+import org.eclipse.team.core.mapping.IStorageMerger;
+import org.eclipse.team.internal.core.*;
+
+/**
+ * This storage merger delegates to the appropriate merger or returns a conflict
+ * if no merger is available.
+ * <p>
+ * The target storage is used to look for an appropriate merger. If the target
+ * is an {@link IFile}, the content type of the file is used. Otherwise, the
+ * {@link IContentTypeManager} is used to find an appropriate content type.If an
+ * appropriate merger is not found, a status containing the
+ * <code>CONFLICT</code> is returned.
+ * 
+ */
+public class DelegatingStorageMerger implements IStorageMerger {
+
+	private static IStreamMergerDelegate mergerDelegate;
+	private static DelegatingStorageMerger instance;
+	private final IContentType contentType;
+	
+	private DelegatingStorageMerger() {
+		contentType = null;
+	}
+	
+	public DelegatingStorageMerger(IContentType contentType) {
+		this.contentType = contentType;
+	}
+
+	/**
+	 * Set the file merger that is used by the {@link #performThreeWayMerge(IThreeWayDiff, IProgressMonitor) }
+	 * method. It is the responsibility of subclasses to provide a merger.
+	 * If a merger is not provided, subclasses must override <code>performThreeWayMerge</code>.
+	 * @param merger the merger used to merge files
+	 */
+	public static void setMergerDelegate(IStreamMergerDelegate aMerger) {
+		mergerDelegate = aMerger;
+	}
+	
+	public static IStorageMerger getInstance() {
+		if (instance == null)
+			instance = new DelegatingStorageMerger();
+		return instance;
+	}
+	
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.team.core.mapping.IStorageMerger#merge(java.io.OutputStream,
+	 *      java.lang.String, org.eclipse.core.resources.IStorage,
+	 *      org.eclipse.core.resources.IStorage,
+	 *      org.eclipse.core.resources.IStorage,
+	 *      org.eclipse.core.runtime.IProgressMonitor)
+	 */
+	public IStatus merge(OutputStream output, String outputEncoding,
+			IStorage ancestor, IStorage target, IStorage other,
+			IProgressMonitor monitor) throws CoreException {
+		IStorageMerger merger = findMerger(target);
+		if (merger == null)
+			return new Status(IStatus.WARNING, TeamPlugin.ID, CONFLICT,
+					Messages.DelegatingStorageMerger_0, null);
+		return merger.merge(output, outputEncoding, ancestor, target, other, monitor);
+	}
+
+	private IStorageMerger findMerger(IStorage target) throws CoreException {
+		IStorageMerger merger = null;
+		if (contentType != null) {
+			// A particular merger has been requested
+			merger = getMerger(contentType);
+			if (merger != null) {
+				return merger;
+			} else {
+				// The requested merger is not available but still tryand find another
+				TeamPlugin.log(IStatus.ERROR, NLS.bind("Storage merger for {0} not available", contentType.getId()), null); //$NON-NLS-1$
+			}
+		}
+		CoreException exception = null;
+		try {
+			IContentType type = getContentType(target);
+			if (type != null)
+				merger = getMerger(type);
+		} catch (CoreException e) {
+			exception = e;
+		}
+		// If an exception occurred trying to find a content type,
+		// try using the extension before failing
+		if (merger == null) {
+			merger = getMerger(target.getName());
+			if (merger == null) {
+				// If team thinks the file is text, try to get a text merger for the file
+				int type = Team.getFileContentManager().getType(target);
+				if (type == Team.TEXT) 
+					merger = getTextMerger();
+				if (merger == null) {
+					// As a last resort, look for a stream merger
+					merger = findAndWrapStreamMerger(target);
+				}
+			}
+		}
+		if (exception != null) {
+			if (merger == null) {
+				// No merger was found so report the error
+				throw exception;
+			} else {
+				// If an extension based merger was found, log the error
+				TeamPlugin.log(exception);
+			}
+		}
+		return merger;
+	}
+
+	private IStorageMerger findAndWrapStreamMerger(IStorage target) {
+		if (mergerDelegate != null) {
+			IStorageMerger merger = mergerDelegate.findMerger(target);
+			return merger;
+		}
+		return null;
+	}
+
+	private IStorageMerger getTextMerger() {
+		return new DelegatingStorageMerger(Platform.getContentTypeManager().getContentType(IContentTypeManager.CT_TEXT));
+	}
+
+	private IStorageMerger getMerger(String name) {
+		String extension = getExtension(name);
+		if (extension != null)
+			return StorageMergerRegistry.getInstance().createStreamMerger(extension);
+		return null;
+	}
+
+	public static String getExtension(String name) {
+		int index = name.lastIndexOf('.');
+		if (index == -1) {
+			return null;
+		}
+		return name.substring(index + 1);
+	}
+
+	private IStorageMerger getMerger(IContentType type) {
+		IStorageMerger merger = StorageMergerRegistry.getInstance().createStreamMerger(type);
+		return merger;
+	}
+
+	/*
+	 * Find the content type for the given storage and return null if a content
+	 * type cannot be found. Any exceptions that occur when trying to determine
+	 * the content type are propogated.
+	 */
+	public static IContentType getContentType(IStorage target) throws CoreException {
+		if (target instanceof IFile) {
+			IFile file = (IFile) target;
+			IContentDescription contentDescription = file.getContentDescription();
+			if (contentDescription != null) {
+				IContentType contentType = contentDescription.getContentType();
+				return contentType;
+			}
+		} else {
+			IContentTypeManager manager = Platform.getContentTypeManager();
+			try {
+				IContentType type = manager.findContentTypeFor(target
+						.getContents(), target.getName());
+				return type;
+			} catch (IOException e) {
+				String name = target.getName();
+				if (target.getFullPath() != null) {
+					name = target.getFullPath().toString();
+				}
+				throw new TeamException(new Status(
+					IStatus.ERROR,
+					TeamPlugin.ID,
+					INTERNAL_ERROR,
+					NLS.bind(Messages.DelegatingStorageMerger_1,name), e));
+			}
+		}
+		return null;
+	}
+
+}