Reuse Merger's ObjectReader from ResolveMerger

The base Merger class already has a single ObjectReader instance that
it handles releasing as necessary, so creating new readers is not
necessary.

Change-Id: I990ec43af7df448c7825fc1b10e62eadaa3e0c2a

org.eclipse.jgit/src/org/eclipse/jgit/merge/ResolveMerger.java

@@ -81,7 +81,6 @@ import org.eclipse.jgit.internal.JGitText;
 import org.eclipse.jgit.lib.ConfigConstants;
 import org.eclipse.jgit.lib.FileMode;
 import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.lib.ObjectReader;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.revwalk.RevTree;
 import org.eclipse.jgit.treewalk.AbstractTreeIterator;
@@ -309,13 +308,11 @@ public class ResolveMerger extends ThreeWayMerger {
 	}
 
 	private void checkout() throws NoWorkTreeException, IOException {
-		ObjectReader r = db.getObjectDatabase().newReader();
-		try {
 		for (Map.Entry<String, DirCacheEntry> entry : toBeCheckedOut
 				.entrySet()) {
 			File f = new File(db.getWorkTree(), entry.getKey());
 			createDir(f.getParentFile());
-				DirCacheCheckout.checkoutEntry(db, f, entry.getValue(), r);
+			DirCacheCheckout.checkoutEntry(db, f, entry.getValue(), reader);
 			modifiedFiles.add(entry.getKey());
 		}
 		// Iterate in reverse so that "folder/file" is deleted before
@@ -330,9 +327,6 @@ public class ResolveMerger extends ThreeWayMerger {
 							MergeFailureReason.COULD_NOT_DELETE);
 			modifiedFiles.add(fileName);
 		}
-		} finally {
-			r.release();
-		}
 	}
 
 	private void createDir(File f) throws IOException {
@@ -368,7 +362,6 @@ public class ResolveMerger extends ThreeWayMerger {
 		}
 
 		DirCache dc = db.readDirCache();
-		ObjectReader or = db.getObjectDatabase().newReader();
 		Iterator<String> mpathsIt=modifiedFiles.iterator();
 		while(mpathsIt.hasNext()) {
 			String mpath=mpathsIt.next();
@@ -378,7 +371,7 @@ public class ResolveMerger extends ThreeWayMerger {
 			FileOutputStream fos = new FileOutputStream(new File(
 					db.getWorkTree(), mpath));
 			try {
-				or.open(entry.getObjectId()).copyTo(fos);
+				reader.open(entry.getObjectId()).copyTo(fos);
 			} finally {
 				fos.close();
 			}