Make streamFileThreshold configurable

Previously, the streamFileThreshold, the threshold at which a file
would be streamed rather than loaded entirely into memory, was only
configurable on a global basis.

This commit makes this threshold configurable on a per-loader basis.

Bug: 490404
Change-Id: I492c18c3155dbf56eedda9044a61d76120fd75f9
Signed-off-by: Kevin Corcoran <kevin.corcoran@puppetlabs.com>
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

4 files changed, 53 insertions, 8 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackFileTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackFileTest.java
index ba07d6842f..1c10bb335a 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackFileTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackFileTest.java
@@ -310,6 +310,27 @@ public class PackFileTest extends LocalDiskRepositoryTestCase {
 		}
 	}
 
+	@Test
+	public void testConfigurableStreamFileThreshold() throws Exception {
+		byte[] data = getRng().nextBytes(300);
+		RevBlob id = tr.blob(data);
+		tr.branch("master").commit().add("A", id).create();
+		tr.packAndPrune();
+		assertTrue("has blob", wc.has(id));
+
+		ObjectLoader ol = wc.open(id);
+		ObjectStream in = ol.openStream();
+		assertTrue(in instanceof ObjectStream.SmallStream);
+		assertEquals(300, in.available());
+		in.close();
+
+		wc.setStreamFileThreshold(299);
+		ol = wc.open(id);
+		in = ol.openStream();
+		assertTrue(in instanceof ObjectStream.Filter);
+		assertEquals(1, in.available());
+	}
+
 	private static byte[] clone(int first, byte[] base) {
 		byte[] r = new byte[base.length];
 		System.arraycopy(base, 1, r, 1, r.length - 1);
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsReader.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsReader.java
index 2f61dea0d5..8c9329503f 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsReader.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsReader.java
@@ -113,6 +113,7 @@ public final class DfsReader extends ObjectReader implements ObjectReuseAsIs {
 
 	DfsReader(DfsObjDatabase db) {
 		this.db = db;
+		this.streamFileThreshold = db.getReaderOptions().getStreamFileThreshold();
 	}
 
 	DfsReaderOptions getOptions() {
@@ -125,10 +126,6 @@ public final class DfsReader extends ObjectReader implements ObjectReuseAsIs {
 		return baseCache;
 	}
 
-	int getStreamFileThreshold() {
-		return getOptions().getStreamFileThreshold();
-	}
-
 	@Override
 	public ObjectReader newReader() {
 		return new DfsReader(db);
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/WindowCursor.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/WindowCursor.java
index a2c0561ae1..a742d1747e 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/WindowCursor.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/WindowCursor.java
@@ -94,12 +94,14 @@ final class WindowCursor extends ObjectReader implements ObjectReuseAsIs {
 	WindowCursor(FileObjectDatabase db) {
 		this.db = db;
 		this.createdFromInserter = null;
+		this.streamFileThreshold = WindowCache.getStreamFileThreshold();
 	}
 
 	WindowCursor(FileObjectDatabase db,
 			@Nullable ObjectDirectoryInserter createdFromInserter) {
 		this.db = db;
 		this.createdFromInserter = createdFromInserter;
+		this.streamFileThreshold = WindowCache.getStreamFileThreshold();
 	}
 
 	DeltaBaseCache getDeltaBaseCache() {
@@ -337,10 +339,6 @@ final class WindowCursor extends ObjectReader implements ObjectReuseAsIs {
 		}
 	}
 
-	int getStreamFileThreshold() {
-		return WindowCache.getStreamFileThreshold();
-	}
-
 	@Override
 	@Nullable
 	public ObjectInserter getCreatedFromInserter() {
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectReader.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectReader.java
index b23145d798..263fc99745 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectReader.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectReader.java
@@ -66,6 +66,12 @@ public abstract class ObjectReader implements AutoCloseable {
 	public static final int OBJ_ANY = -1;
 
 	/**
+	 * The threshold at which a file will be streamed rather than
+	 * loaded entirely into memory.
+	 */
+	protected int streamFileThreshold;
+
+	/**
 	 * Construct a new reader from the same data.
 	 * <p>
 	 * Applications can use this method to build a new reader from the same data
@@ -445,6 +451,29 @@ public abstract class ObjectReader implements AutoCloseable {
 	public abstract void close();
 
 	/**
+	 * Sets the threshold at which a file will be streamed rather than loaded
+	 * entirely into memory
+	 *
+	 * @param threshold
+	 *            the new threshold
+	 * @since 4.6
+	 */
+	public void setStreamFileThreshold(int threshold) {
+		streamFileThreshold = threshold;
+	}
+
+	/**
+	 * Returns the threshold at which a file will be streamed rather than loaded
+	 * entirely into memory
+	 *
+	 * @return the threshold in bytes
+	 * @since 4.6
+	 */
+	public int getStreamFileThreshold() {
+		return streamFileThreshold;
+	}
+
+	/**
 	 * Wraps a delegate ObjectReader.
 	 *
 	 * @since 4.4