Extract ObjectToPack to be top-level

This shortens the implementation within PackWriter, and starts
to open the door for some other refactorings based on changing
the ObjectToPack to be a public part of the API.

Change-Id: Id849cbffc4de20b903e844a2de7737eeb8b7a3ff
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

2 files changed, 191 insertions, 143 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectToPack.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectToPack.java
new file mode 100644
index 0000000000..75378cec14
--- /dev/null
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectToPack.java
@@ -0,0 +1,191 @@
+/*
+ * Copyright (C) 2008-2010, Google Inc.
+ * Copyright (C) 2008, Marek Zawirski <marek.zawirski@gmail.com>
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - 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.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. 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 COPYRIGHT OWNER 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.
+ */
+
+package org.eclipse.jgit.lib;
+
+import java.io.IOException;
+
+import org.eclipse.jgit.transport.PackedObjectInfo;
+
+/**
+ * Class holding information about object that is going to be packed by
+ * {@link PackWriter}. Information include object representation in a
+ * pack-file and object status.
+ *
+ */
+class ObjectToPack extends PackedObjectInfo {
+	/** Other object being packed that this will delta against. */
+	private ObjectId deltaBase;
+
+	/** Pack to reuse compressed data from, otherwise null. */
+	private PackFile copyFromPack;
+
+	/** Offset of the object's header in {@link #copyFromPack}. */
+	private long copyOffset;
+
+	/**
+	 * Bit field, from bit 0 to bit 31:
+	 * <ul>
+	 * <li>1 bit: wantWrite</li>
+	 * <li>3 bits: type</li>
+	 * <li>28 bits: deltaDepth</li>
+	 * </ul>
+	 */
+	private int flags;
+
+	/**
+	 * Construct object for specified object id. <br/> By default object is
+	 * marked as not written and non-delta packed (as a whole object).
+	 *
+	 * @param src
+	 *            object id of object for packing
+	 * @param type
+	 *            real type code of the object, not its in-pack type.
+	 */
+	ObjectToPack(AnyObjectId src, final int type) {
+		super(src);
+		flags |= type << 1;
+	}
+
+	/**
+	 * @return delta base object id if object is going to be packed in delta
+	 *         representation; null otherwise - if going to be packed as a
+	 *         whole object.
+	 */
+	ObjectId getDeltaBaseId() {
+		return deltaBase;
+	}
+
+	/**
+	 * @return delta base object to pack if object is going to be packed in
+	 *         delta representation and delta is specified as object to
+	 *         pack; null otherwise - if going to be packed as a whole
+	 *         object or delta base is specified only as id.
+	 */
+	ObjectToPack getDeltaBase() {
+		if (deltaBase instanceof ObjectToPack)
+			return (ObjectToPack) deltaBase;
+		return null;
+	}
+
+	/**
+	 * Set delta base for the object. Delta base set by this method is used
+	 * by {@link PackWriter} to write object - determines its representation
+	 * in a created pack.
+	 *
+	 * @param deltaBase
+	 *            delta base object or null if object should be packed as a
+	 *            whole object.
+	 *
+	 */
+	void setDeltaBase(ObjectId deltaBase) {
+		this.deltaBase = deltaBase;
+	}
+
+	void clearDeltaBase() {
+		this.deltaBase = null;
+	}
+
+	/**
+	 * @return true if object is going to be written as delta; false
+	 *         otherwise.
+	 */
+	boolean isDeltaRepresentation() {
+		return deltaBase != null;
+	}
+
+	/**
+	 * Check if object is already written in a pack. This information is
+	 * used to achieve delta-base precedence in a pack file.
+	 *
+	 * @return true if object is already written; false otherwise.
+	 */
+	boolean isWritten() {
+		return getOffset() != 0;
+	}
+
+	boolean isCopyable() {
+		return copyFromPack != null;
+	}
+
+	PackedObjectLoader getCopyLoader(WindowCursor curs) throws IOException {
+		return copyFromPack.resolveBase(curs, copyOffset);
+	}
+
+	void setCopyFromPack(PackedObjectLoader loader) {
+		this.copyFromPack = loader.pack;
+		this.copyOffset = loader.objectOffset;
+	}
+
+	void clearSourcePack() {
+		copyFromPack = null;
+	}
+
+	int getType() {
+		return (flags>>1) & 0x7;
+	}
+
+	int getDeltaDepth() {
+		return flags >>> 4;
+	}
+
+	void updateDeltaDepth() {
+		final int d;
+		if (deltaBase instanceof ObjectToPack)
+			d = ((ObjectToPack) deltaBase).getDeltaDepth() + 1;
+		else if (deltaBase != null)
+			d = 1;
+		else
+			d = 0;
+		flags = (d << 4) | flags & 0x15;
+	}
+
+	boolean wantWrite() {
+		return (flags & 1) == 1;
+	}
+
+	void markWantWrite() {
+		flags |= 1;
+	}
+}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/PackWriter.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/PackWriter.java
index 15ac17425e..4128345ab9 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/PackWriter.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/PackWriter.java
@@ -61,7 +61,6 @@ import org.eclipse.jgit.revwalk.ObjectWalk;
 import org.eclipse.jgit.revwalk.RevFlag;
 import org.eclipse.jgit.revwalk.RevObject;
 import org.eclipse.jgit.revwalk.RevSort;
-import org.eclipse.jgit.transport.PackedObjectInfo;
 import org.eclipse.jgit.util.NB;
 
 /**
@@ -899,146 +898,4 @@ public class PackWriter {
 		}
 		objectsMap.add(otp);
 	}
-
-	/**
-	 * Class holding information about object that is going to be packed by
-	 * {@link PackWriter}. Information include object representation in a
-	 * pack-file and object status.
-	 *
-	 */
-	static class ObjectToPack extends PackedObjectInfo {
-		/** Other object being packed that this will delta against. */
-		private ObjectId deltaBase;
-
-		/** Pack to reuse compressed data from, otherwise null. */
-		private PackFile copyFromPack;
-
-		/** Offset of the object's header in {@link #copyFromPack}. */
-		private long copyOffset;
-
-		/**
-		 * Bit field, from bit 0 to bit 31:
-		 * <ul>
-		 * <li>1 bit: wantWrite</li>
-		 * <li>3 bits: type</li>
-		 * <li>28 bits: deltaDepth</li>
-		 * </ul>
-		 */
-		private int flags;
-
-		/**
-		 * Construct object for specified object id. <br/> By default object is
-		 * marked as not written and non-delta packed (as a whole object).
-		 *
-		 * @param src
-		 *            object id of object for packing
-		 * @param type
-		 *            real type code of the object, not its in-pack type.
-		 */
-		ObjectToPack(AnyObjectId src, final int type) {
-			super(src);
-			flags |= type << 1;
-		}
-
-		/**
-		 * @return delta base object id if object is going to be packed in delta
-		 *         representation; null otherwise - if going to be packed as a
-		 *         whole object.
-		 */
-		ObjectId getDeltaBaseId() {
-			return deltaBase;
-		}
-
-		/**
-		 * @return delta base object to pack if object is going to be packed in
-		 *         delta representation and delta is specified as object to
-		 *         pack; null otherwise - if going to be packed as a whole
-		 *         object or delta base is specified only as id.
-		 */
-		ObjectToPack getDeltaBase() {
-			if (deltaBase instanceof ObjectToPack)
-				return (ObjectToPack) deltaBase;
-			return null;
-		}
-
-		/**
-		 * Set delta base for the object. Delta base set by this method is used
-		 * by {@link PackWriter} to write object - determines its representation
-		 * in a created pack.
-		 *
-		 * @param deltaBase
-		 *            delta base object or null if object should be packed as a
-		 *            whole object.
-		 *
-		 */
-		void setDeltaBase(ObjectId deltaBase) {
-			this.deltaBase = deltaBase;
-		}
-
-		void clearDeltaBase() {
-			this.deltaBase = null;
-		}
-
-		/**
-		 * @return true if object is going to be written as delta; false
-		 *         otherwise.
-		 */
-		boolean isDeltaRepresentation() {
-			return deltaBase != null;
-		}
-
-		/**
-		 * Check if object is already written in a pack. This information is
-		 * used to achieve delta-base precedence in a pack file.
-		 *
-		 * @return true if object is already written; false otherwise.
-		 */
-		boolean isWritten() {
-			return getOffset() != 0;
-		}
-
-		boolean isCopyable() {
-			return copyFromPack != null;
-		}
-
-		PackedObjectLoader getCopyLoader(WindowCursor curs) throws IOException {
-			return copyFromPack.resolveBase(curs, copyOffset);
-		}
-
-		void setCopyFromPack(PackedObjectLoader loader) {
-			this.copyFromPack = loader.pack;
-			this.copyOffset = loader.objectOffset;
-		}
-
-		void clearSourcePack() {
-			copyFromPack = null;
-		}
-
-		int getType() {
-			return (flags>>1) & 0x7;
-		}
-
-		int getDeltaDepth() {
-			return flags >>> 4;
-		}
-
-		void updateDeltaDepth() {
-			final int d;
-			if (deltaBase instanceof ObjectToPack)
-				d = ((ObjectToPack) deltaBase).getDeltaDepth() + 1;
-			else if (deltaBase != null)
-				d = 1;
-			else
-				d = 0;
-			flags = (d << 4) | flags & 0x15;
-		}
-
-		boolean wantWrite() {
-			return (flags & 1) == 1;
-		}
-
-		void markWantWrite() {
-			flags |= 1;
-		}
-	}
 }