implementing git diff viewer

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/GitDiffViewer.java

@@ -0,0 +1,168 @@
+/**
+ * Copyright (c) 2010, Sebastian Sdorra
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. Neither the name of SCM-Manager; nor the names of its
+ *    contributors may be used to endorse or promote products derived from this
+ *    software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * http://bitbucket.org/sdorra/scm-manager
+ *
+ */
+
+
+
+package sonia.scm.repository;
+
+//~--- non-JDK imports --------------------------------------------------------
+
+import org.eclipse.jgit.diff.DiffEntry;
+import org.eclipse.jgit.diff.DiffFormatter;
+import org.eclipse.jgit.revwalk.RevCommit;
+import org.eclipse.jgit.revwalk.RevTree;
+import org.eclipse.jgit.revwalk.RevWalk;
+import org.eclipse.jgit.treewalk.EmptyTreeIterator;
+import org.eclipse.jgit.treewalk.TreeWalk;
+
+//~--- JDK imports ------------------------------------------------------------
+
+import java.io.BufferedOutputStream;
+import java.io.File;
+import java.io.IOException;
+import java.io.OutputStream;
+
+import java.util.List;
+
+/**
+ *
+ * @author Sebastian Sdorra
+ */
+public class GitDiffViewer implements DiffViewer
+{
+
+  /**
+   * Constructs ...
+   *
+   *
+   * @param directory
+   */
+  public GitDiffViewer(File directory)
+  {
+    this.directory = directory;
+  }
+
+  /**
+   * Constructs ...
+   *
+   *
+   * @param handler
+   * @param repository
+   */
+  public GitDiffViewer(GitRepositoryHandler handler, Repository repository)
+  {
+    this(handler.getDirectory(repository));
+  }
+
+  //~--- get methods ----------------------------------------------------------
+
+  /**
+   * Method description
+   *
+   *
+   * @param revision
+   * @param path
+   * @param output
+   *
+   * @throws IOException
+   * @throws RepositoryException
+   */
+  @Override
+  public void getDiff(String revision, String path, OutputStream output)
+          throws IOException, RepositoryException
+  {
+    org.eclipse.jgit.lib.Repository gr = GitUtil.open(directory);
+    RevWalk walk = null;
+    TreeWalk treeWalk = null;
+    DiffFormatter formatter = null;
+
+    try
+    {
+
+      // TODO set path if is set
+      walk = new RevWalk(gr);
+
+      RevCommit commit = walk.parseCommit(gr.resolve(revision));
+
+      walk.markStart(commit);
+      commit = walk.next();
+      treeWalk = new TreeWalk(gr);
+      treeWalk.reset();
+      treeWalk.setRecursive(true);
+
+      if (commit.getParentCount() > 0)
+      {
+        RevTree tree = commit.getParent(0).getTree();
+
+        if (tree != null)
+        {
+          treeWalk.addTree(tree);
+        }
+        else
+        {
+          treeWalk.addTree(new EmptyTreeIterator());
+        }
+      }
+      else
+      {
+        treeWalk.addTree(new EmptyTreeIterator());
+      }
+
+      treeWalk.addTree(commit.getTree());
+      formatter = new DiffFormatter(new BufferedOutputStream(output));
+      formatter.setRepository(gr);
+
+      List<DiffEntry> entries = DiffEntry.scan(treeWalk);
+
+      for (DiffEntry e : entries)
+      {
+        if (!e.getOldId().equals(e.getNewId()))
+        {
+          formatter.format(e);
+        }
+      }
+
+      formatter.flush();
+    }
+    finally
+    {
+      GitUtil.release(walk);
+      GitUtil.release(treeWalk);
+      GitUtil.release(formatter);
+      GitUtil.close(gr);
+    }
+  }
+
+  //~--- fields ---------------------------------------------------------------
+
+  /** Field description */
+  private File directory;
+}

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/GitRepositoryHandler.java

@@ -144,12 +144,43 @@ public class GitRepositoryHandler
     }
     else
     {
-      throw new IllegalArgumentException("mercurial repository is required");
+      throw new IllegalArgumentException("git repository is required");
     }
 
     return changesetViewer;
   }
 
+  /**
+   * Method description
+   *
+   *
+   * @param repository
+   *
+   * @return
+   */
+  @Override
+  public DiffViewer getDiffViewer(Repository repository)
+  {
+    GitDiffViewer diffViewer = null;
+
+    AssertUtil.assertIsNotNull(repository);
+
+    String type = repository.getType();
+
+    AssertUtil.assertIsNotEmpty(type);
+
+    if (TYPE_NAME.equals(type))
+    {
+      diffViewer = new GitDiffViewer(this, repository);
+    }
+    else
+    {
+      throw new IllegalArgumentException("git repository is required");
+    }
+
+    return diffViewer;
+  }
+
   /**
    * Method description
    *

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/GitUtil.java

@@ -55,6 +55,7 @@ import java.io.File;
 import java.io.IOException;
 
 import java.util.Map;
+import org.eclipse.jgit.diff.DiffFormatter;
 
 /**
  *
@@ -93,6 +94,12 @@ public class GitUtil
       repo.close();
     }
   }
+  
+  public static void release(DiffFormatter formatter){
+    if ( formatter != null ){
+      formatter.release();
+    }
+  }
 
   /**
    * Method description