From f799b5d6b51c05ddfe7ed36ad4e3846506133a20 Mon Sep 17 00:00:00 2001
From: "Shawn O. Pearce" <spearce@spearce.org>
Date: Mon, 11 Aug 2008 18:07:52 -0700
Subject: [PATCH] Allow AbstractTreeIterators to find out about
 StopWalkExceptions

If a tree iterator has overridden skip() to specially handle entries
which the TreeWalk has decided are not relevant then it might also
need to pay attention to a StopWalkException.  The SWE is thrown out
of a filter and behaves much like skip, except it skips everything
else in the tree.  This is used by PathFilterGroup to break out of
a walk once we know that no additional records could ever match.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
---
 .../src/org/spearce/jgit/treewalk/AbstractTreeIterator.java   | 11 +++++++++++
 .../src/org/spearce/jgit/treewalk/EmptyTreeIterator.java      |  6 ++++++
 org.spearce.jgit/src/org/spearce/jgit/treewalk/TreeWalk.java  |  2 ++
 3 files changed, 19 insertions(+)

diff --git a/org.spearce.jgit/src/org/spearce/jgit/treewalk/AbstractTreeIterator.java b/org.spearce.jgit/src/org/spearce/jgit/treewalk/AbstractTreeIterator.java
index c9c9f8a9..232204a3 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/treewalk/AbstractTreeIterator.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/treewalk/AbstractTreeIterator.java
@@ -391,4 +391,15 @@ public abstract class AbstractTreeIterator {
 	public void skip() throws CorruptObjectException {
 		next();
 	}
+
+	/**
+	 * Indicates to the iterator that no more entries will be read.
+	 * <p>
+	 * This is only invoked by TreeWalk when the iteration is aborted early due
+	 * to a {@link org.spearce.jgit.errors.StopWalkException} being thrown from
+	 * within a TreeFilter.
+	 */
+	public void stopWalk() {
+		// Do nothing by default.  Most iterators do not care.
+	}
 }
diff --git a/org.spearce.jgit/src/org/spearce/jgit/treewalk/EmptyTreeIterator.java b/org.spearce.jgit/src/org/spearce/jgit/treewalk/EmptyTreeIterator.java
index 09d2bde7..c5dc4adb 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/treewalk/EmptyTreeIterator.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/treewalk/EmptyTreeIterator.java
@@ -87,4 +87,10 @@ public class EmptyTreeIterator extends AbstractTreeIterator {
 	public void next() throws CorruptObjectException {
 		// Do nothing.
 	}
+
+	@Override
+	public void stopWalk() {
+		if (parent != null)
+			parent.stopWalk();
+	}
 }
diff --git a/org.spearce.jgit/src/org/spearce/jgit/treewalk/TreeWalk.java b/org.spearce.jgit/src/org/spearce/jgit/treewalk/TreeWalk.java
index 6824a0e6..969ee3fb 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/treewalk/TreeWalk.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/treewalk/TreeWalk.java
@@ -408,6 +408,8 @@ public class TreeWalk {
 				return true;
 			}
 		} catch (StopWalkException stop) {
+			for (final AbstractTreeIterator t : trees)
+				t.stopWalk();
 			return false;
 		}
 	}
-- 
2.11.4.GIT