Replace trivial reference comparison of PacketLineIn.{DELIM,END}

Replace reference comparisons of PacketLineIn's DELIM and END strings
with usage of the helper methods isDelimiter() and isEnd().

Change-Id: I52dcfc4ee9097f1bd6970601c716701847d9eebd
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

14 files changed, 64 insertions, 66 deletions

diff --git a/org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/HttpClientTests.java b/org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/HttpClientTests.java
index 1660f14f34..4158049171 100644
--- a/org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/HttpClientTests.java
+++ b/org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/HttpClientTests.java
@@ -44,7 +44,6 @@
 package org.eclipse.jgit.http.test;
 
 import static org.hamcrest.Matchers.is;
-import static org.hamcrest.Matchers.theInstance;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
@@ -366,7 +365,7 @@ public class HttpClientTests extends HttpTestCase {
 
 		// Check that we get a v0 response.
 		assertThat(pckIn.readString(), is("# service=git-upload-pack"));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.END));
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 		assertTrue(pckIn.readString().matches("[0-9a-f]{40} HEAD.*"));
 	}
 
diff --git a/org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/ProtocolErrorTest.java b/org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/ProtocolErrorTest.java
index f0fac5ab51..6a3d8829bb 100644
--- a/org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/ProtocolErrorTest.java
+++ b/org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/ProtocolErrorTest.java
@@ -44,7 +44,7 @@
 package org.eclipse.jgit.http.test;
 
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertTrue;
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
@@ -157,7 +157,7 @@ public class ProtocolErrorTest extends HttpTestCase {
 						pckin.readString());
 				assertEquals("ng refs/objects/A n/a (unpacker error)",
 						pckin.readString());
-				assertSame(PacketLineIn.END, pckin.readString());
+				assertTrue(PacketLineIn.isEnd(pckin.readString()));
 			}
 		} finally {
 			c.disconnect();
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV0ParserTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV0ParserTest.java
index 28a9c03ecc..42553147fb 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV0ParserTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV0ParserTest.java
@@ -64,9 +64,9 @@ public class ProtocolV0ParserTest {
 		ByteArrayOutputStream send = new ByteArrayOutputStream();
 		PacketLineOut pckOut = new PacketLineOut(send);
 		for (String line : inputLines) {
-			if (line == PacketLineIn.END) {
+			if (PacketLineIn.isEnd(line)) {
 				pckOut.end();
-			} else if (line == PacketLineIn.DELIM) {
+			} else if (PacketLineIn.isDelimiter(line)) {
 				pckOut.writeDelim();
 			} else {
 				pckOut.writeString(line);
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV2ParserTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV2ParserTest.java
index 7d6e300fd3..43da170b69 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV2ParserTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV2ParserTest.java
@@ -123,9 +123,9 @@ public class ProtocolV2ParserTest {
 		ByteArrayOutputStream send = new ByteArrayOutputStream();
 		PacketLineOut pckOut = new PacketLineOut(send);
 		for (String line : inputLines) {
-			if (line == PacketLineIn.END) {
+			if (PacketLineIn.isEnd(line)) {
 				pckOut.end();
-			} else if (line == PacketLineIn.DELIM) {
+			} else if (PacketLineIn.isDelimiter(line)) {
 				pckOut.writeDelim();
 			} else {
 				pckOut.writeString(line);
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ReceivePackAdvertiseRefsHookTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ReceivePackAdvertiseRefsHookTest.java
index 50c8a29543..5d208eea73 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ReceivePackAdvertiseRefsHookTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ReceivePackAdvertiseRefsHookTest.java
@@ -306,11 +306,11 @@ public class ReceivePackAdvertiseRefsHookTest extends LocalDiskRepositoryTestCas
 		int nul = master.indexOf('\0');
 		assertTrue("has capability list", nul > 0);
 		assertEquals(B.name() + ' ' + R_MASTER, master.substring(0, nul));
-		assertSame(PacketLineIn.END, r.readString());
+		assertTrue(PacketLineIn.isEnd(r.readString()));
 
 		assertEquals("unpack error Missing commit " + P.name(), r.readString());
 		assertEquals("ng refs/heads/s n/a (unpacker error)", r.readString());
-		assertSame(PacketLineIn.END, r.readString());
+		assertTrue(PacketLineIn.isEnd(r.readString()));
 	}
 
 	private static void receive(final ReceivePack rp,
@@ -366,13 +366,13 @@ public class ReceivePackAdvertiseRefsHookTest extends LocalDiskRepositoryTestCas
 			int nul = master.indexOf('\0');
 			assertTrue("has capability list", nul > 0);
 			assertEquals(B.name() + ' ' + R_MASTER, master.substring(0, nul));
-			assertSame(PacketLineIn.END, r.readString());
+			assertTrue(PacketLineIn.isEnd(r.readString()));
 
 			assertEquals("unpack error Missing blob " + b.name(),
 					r.readString());
 			assertEquals("ng refs/heads/s n/a (unpacker error)",
 					r.readString());
-			assertSame(PacketLineIn.END, r.readString());
+			assertTrue(PacketLineIn.isEnd(r.readString()));
 		}
 	}
 
@@ -419,13 +419,13 @@ public class ReceivePackAdvertiseRefsHookTest extends LocalDiskRepositoryTestCas
 			int nul = master.indexOf('\0');
 			assertTrue("has capability list", nul > 0);
 			assertEquals(B.name() + ' ' + R_MASTER, master.substring(0, nul));
-			assertSame(PacketLineIn.END, r.readString());
+			assertTrue(PacketLineIn.isEnd(r.readString()));
 
 			assertEquals("unpack error Missing blob " + b.name(),
 					r.readString());
 			assertEquals("ng refs/heads/s n/a (unpacker error)",
 					r.readString());
-			assertSame(PacketLineIn.END, r.readString());
+			assertTrue(PacketLineIn.isEnd(r.readString()));
 		}
 	}
 
@@ -473,13 +473,13 @@ public class ReceivePackAdvertiseRefsHookTest extends LocalDiskRepositoryTestCas
 			int nul = master.indexOf('\0');
 			assertTrue("has capability list", nul > 0);
 			assertEquals(B.name() + ' ' + R_MASTER, master.substring(0, nul));
-			assertSame(PacketLineIn.END, r.readString());
+			assertTrue(PacketLineIn.isEnd(r.readString()));
 
 			assertEquals("unpack error Missing blob " + n.name(),
 					r.readString());
 			assertEquals("ng refs/heads/s n/a (unpacker error)",
 					r.readString());
-			assertSame(PacketLineIn.END, r.readString());
+			assertTrue(PacketLineIn.isEnd(r.readString()));
 		}
 	}
 
@@ -504,13 +504,13 @@ public class ReceivePackAdvertiseRefsHookTest extends LocalDiskRepositoryTestCas
 		int nul = master.indexOf('\0');
 		assertTrue("has capability list", nul > 0);
 		assertEquals(B.name() + ' ' + R_MASTER, master.substring(0, nul));
-		assertSame(PacketLineIn.END, r.readString());
+		assertTrue(PacketLineIn.isEnd(r.readString()));
 
 		String errorLine = r.readString();
 		assertTrue(errorLine.startsWith("unpack error"));
 		assertTrue(errorLine.contains("Invalid submodule URL '-"));
 		assertEquals("ng refs/heads/s n/a (unpacker error)", r.readString());
-		assertSame(PacketLineIn.END, r.readString());
+		assertTrue(PacketLineIn.isEnd(r.readString()));
 	}
 
 	private TemporaryBuffer.Heap setupSourceRepoInvalidGitmodules()
@@ -589,13 +589,13 @@ public class ReceivePackAdvertiseRefsHookTest extends LocalDiskRepositoryTestCas
 			int nul = master.indexOf('\0');
 			assertTrue("has capability list", nul > 0);
 			assertEquals(B.name() + ' ' + R_MASTER, master.substring(0, nul));
-			assertSame(PacketLineIn.END, r.readString());
+			assertTrue(PacketLineIn.isEnd(r.readString()));
 
 			assertEquals("unpack error Missing tree " + t.name(),
 					r.readString());
 			assertEquals("ng refs/heads/s n/a (unpacker error)",
 					r.readString());
-			assertSame(PacketLineIn.END, r.readString());
+			assertTrue(PacketLineIn.isEnd(r.readString()));
 		}
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/RefAdvertiserTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/RefAdvertiserTest.java
index ce69adf9c1..ccb548d919 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/RefAdvertiserTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/RefAdvertiserTest.java
@@ -45,7 +45,7 @@ package org.eclipse.jgit.transport;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertTrue;
 
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
@@ -95,7 +95,7 @@ public class RefAdvertiserTest {
 		assertEquals(id(3).name() + " refs/Iñtërnâtiônàlizætiøn☃💩\n", s);
 
 		s = pckIn.readStringRaw();
-		assertSame(PacketLineIn.END, s);
+		assertTrue(PacketLineIn.isEnd(s));
 	}
 
 	private static ObjectId id(int i) {
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/UploadPackTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/UploadPackTest.java
index 3ead31dbd7..0ad1e2152c 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/UploadPackTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/UploadPackTest.java
@@ -4,7 +4,6 @@ import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.hasItems;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
-import static org.hamcrest.Matchers.theInstance;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
@@ -428,9 +427,9 @@ public class UploadPackTest {
 		try (ByteArrayOutputStream send = new ByteArrayOutputStream()) {
 			PacketLineOut pckOut = new PacketLineOut(send);
 			for (String line : inputLines) {
-				if (line == PacketLineIn.END) {
+				if (PacketLineIn.isEnd(line)) {
 					pckOut.end();
-				} else if (line == PacketLineIn.DELIM) {
+				} else if (PacketLineIn.isDelimiter(line)) {
 					pckOut.writeDelim();
 				} else {
 					pckOut.writeString(line);
@@ -453,7 +452,7 @@ public class UploadPackTest {
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		// drain capabilities
-		while (pckIn.readString() != PacketLineIn.END) {
+		while (!PacketLineIn.isEnd(pckIn.readString())) {
 			// do nothing
 		}
 		return recvStream;
@@ -504,7 +503,7 @@ public class UploadPackTest {
 				// and additional capabilities to be added to existing
 				// commands without requiring test changes.
 				hasItems("ls-refs", "fetch=shallow", "server-option"));
-		assertTrue(pckIn.readString() == PacketLineIn.END);
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -521,7 +520,7 @@ public class UploadPackTest {
 				// TODO(jonathantanmy) This check overspecifies the
 				// order of the capabilities of "fetch".
 				hasItems("ls-refs", "fetch=filter shallow", "server-option"));
-		assertTrue(pckIn.readString() == PacketLineIn.END);
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -539,7 +538,7 @@ public class UploadPackTest {
 				// order of the capabilities of "fetch".
 				hasItems("ls-refs", "fetch=ref-in-want shallow",
 						"server-option"));
-		assertTrue(pckIn.readString() == PacketLineIn.END);
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -554,7 +553,7 @@ public class UploadPackTest {
 				Arrays.asList(pckIn.readString(), pckIn.readString(),
 						pckIn.readString()),
 				hasItems("ls-refs", "fetch=shallow", "server-option"));
-		assertTrue(pckIn.readString() == PacketLineIn.END);
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -570,7 +569,7 @@ public class UploadPackTest {
 				Arrays.asList(pckIn.readString(), pckIn.readString(),
 						pckIn.readString()),
 				hasItems("ls-refs", "fetch=shallow", "server-option"));
-		assertTrue(pckIn.readString() == PacketLineIn.END);
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -598,7 +597,7 @@ public class UploadPackTest {
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " HEAD"));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/master"));
 		assertThat(pckIn.readString(), is(tag.toObjectId().getName() + " refs/tags/tag"));
-		assertTrue(pckIn.readString() == PacketLineIn.END);
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -615,7 +614,7 @@ public class UploadPackTest {
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " HEAD symref-target:refs/heads/master"));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/master"));
 		assertThat(pckIn.readString(), is(tag.toObjectId().getName() + " refs/tags/tag"));
-		assertTrue(pckIn.readString() == PacketLineIn.END);
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -635,7 +634,7 @@ public class UploadPackTest {
 			pckIn.readString(),
 			is(tag.toObjectId().getName() + " refs/tags/tag peeled:"
 				+ tip.toObjectId().getName()));
-		assertTrue(pckIn.readString() == PacketLineIn.END);
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -657,11 +656,11 @@ public class UploadPackTest {
 			pckIn.readString(),
 			is(tag.toObjectId().getName() + " refs/tags/tag peeled:"
 				+ tip.toObjectId().getName()));
-		assertTrue(pckIn.readString() == PacketLineIn.END);
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " HEAD"));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/master"));
 		assertThat(pckIn.readString(), is(tag.toObjectId().getName() + " refs/tags/tag"));
-		assertTrue(pckIn.readString() == PacketLineIn.END);
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -681,7 +680,7 @@ public class UploadPackTest {
 
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/master"));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/other"));
-		assertTrue(pckIn.readString() == PacketLineIn.END);
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -700,7 +699,7 @@ public class UploadPackTest {
 
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/master"));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/other"));
-		assertTrue(pckIn.readString() == PacketLineIn.END);
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -908,7 +907,7 @@ public class UploadPackTest {
 
 		assertThat(pckIn.readString(), is("acknowledgments"));
 		assertThat(pckIn.readString(), is("ACK " + fooParent.toObjectId().getName()));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.END));
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -937,7 +936,7 @@ public class UploadPackTest {
 				"ACK " + fooParent.toObjectId().getName(),
 				"ACK " + barParent.toObjectId().getName()));
 		assertThat(pckIn.readString(), is("ready"));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertFalse(client.getObjectDatabase().has(fooParent.toObjectId()));
@@ -1160,7 +1159,7 @@ public class UploadPackTest {
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("shallow-info"));
 		assertThat(pckIn.readString(), is("shallow " + child.toObjectId().getName()));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertTrue(client.getObjectDatabase().has(child.toObjectId()));
@@ -1198,7 +1197,7 @@ public class UploadPackTest {
 		// sent only if a packfile is sent.
 		assertThat(pckIn.readString(), is("acknowledgments"));
 		assertThat(pckIn.readString(), is("NAK"));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.END));
+		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
@@ -1237,7 +1236,7 @@ public class UploadPackTest {
 		// later than the given deepen-since time.
 		assertThat(pckIn.readString(), is("unshallow " + boundary.toObjectId().getName()));
 
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
@@ -1286,7 +1285,7 @@ public class UploadPackTest {
 				"shallow " + child1.toObjectId().getName(),
 				"shallow " + child2.toObjectId().getName()));
 
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
@@ -1353,7 +1352,7 @@ public class UploadPackTest {
 		// "three" is unshallow because its parent "two" is now available.
 		assertThat(pckIn.readString(), is("unshallow " + three.toObjectId().getName()));
 
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
@@ -1413,7 +1412,7 @@ public class UploadPackTest {
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("shallow-info"));
 		assertThat(pckIn.readString(), is("shallow " + three.toObjectId().getName()));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertFalse(client.getObjectDatabase().has(one.toObjectId()));
@@ -1455,7 +1454,7 @@ public class UploadPackTest {
 				"shallow " + child1.toObjectId().getName(),
 				"shallow " + child2.toObjectId().getName()));
 
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
@@ -1899,7 +1898,7 @@ public class UploadPackTest {
 				hasItems(
 					one.toObjectId().getName() + " refs/heads/one",
 					two.toObjectId().getName() + " refs/heads/two"));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
@@ -1955,7 +1954,7 @@ public class UploadPackTest {
 		assertThat(
 				pckIn.readString(),
 				is(one.toObjectId().getName() + " refs/heads/one"));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
@@ -1987,7 +1986,7 @@ public class UploadPackTest {
 		assertThat(
 				pckIn.readString(),
 				is(one.toObjectId().getName() + " refs/heads/one"));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 
 		// ... but the client does not need the object itself.
 		assertThat(pckIn.readString(), is("packfile"));
@@ -2015,10 +2014,10 @@ public class UploadPackTest {
 		// shallow-info appears first, then wanted-refs.
 		assertThat(pckIn.readString(), is("shallow-info"));
 		assertThat(pckIn.readString(), is("shallow " + child.toObjectId().getName()));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("wanted-refs"));
 		assertThat(pckIn.readString(), is(child.toObjectId().getName() + " refs/heads/branch1"));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertTrue(client.getObjectDatabase().has(child.toObjectId()));
@@ -2050,11 +2049,11 @@ public class UploadPackTest {
 				is("shallow " + one.toObjectId().getName()));
 		assertThat(pckIn.readString(),
 				is("unshallow " + two.toObjectId().getName()));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("wanted-refs"));
 		assertThat(pckIn.readString(),
 				is(three.toObjectId().getName() + " refs/heads/three"));
-		assertThat(pckIn.readString(), theInstance(PacketLineIn.DELIM));
+		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/transport/BasePackConnection.java b/org.eclipse.jgit/src/org/eclipse/jgit/transport/BasePackConnection.java
index 20a5d9da72..e8724b72db 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/transport/BasePackConnection.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/transport/BasePackConnection.java
@@ -201,7 +201,7 @@ abstract class BasePackConnection extends BaseConnection {
 					throw noRepository();
 				throw eof;
 			}
-			if (line == PacketLineIn.END)
+			if (PacketLineIn.isEnd(line))
 				break;
 
 			if (line.startsWith("ERR ")) { //$NON-NLS-1$
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/transport/BaseReceivePack.java b/org.eclipse.jgit/src/org/eclipse/jgit/transport/BaseReceivePack.java
index 1741db97fe..e402de0158 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/transport/BaseReceivePack.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/transport/BaseReceivePack.java
@@ -1282,7 +1282,7 @@ public abstract class BaseReceivePack {
 						return;
 					throw eof;
 				}
-				if (line == PacketLineIn.END) {
+				if (PacketLineIn.isEnd(line)) {
 					break;
 				}
 
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/transport/ProtocolV0Parser.java b/org.eclipse.jgit/src/org/eclipse/jgit/transport/ProtocolV0Parser.java
index 396327aab0..428a45c09d 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/transport/ProtocolV0Parser.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/transport/ProtocolV0Parser.java
@@ -99,7 +99,7 @@ final class ProtocolV0Parser {
 				throw eof;
 			}
 
-			if (line == PacketLineIn.END) {
+			if (PacketLineIn.isEnd(line)) {
 				break;
 			}
 
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/transport/ProtocolV2Parser.java b/org.eclipse.jgit/src/org/eclipse/jgit/transport/ProtocolV2Parser.java
index cb04ff69a9..2c7beedc62 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/transport/ProtocolV2Parser.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/transport/ProtocolV2Parser.java
@@ -92,7 +92,7 @@ final class ProtocolV2Parser {
 		String agentPrefix = OPTION_AGENT + '=';
 
 		String line = pckIn.readString();
-		while (line != PacketLineIn.DELIM && line != PacketLineIn.END) {
+		while (!PacketLineIn.isDelimiter(line) && !PacketLineIn.isEnd(line)) {
 			if (line.startsWith(serverOptionPrefix)) {
 				serverOptionConsumer
 						.accept(line.substring(serverOptionPrefix.length()));
@@ -133,11 +133,11 @@ final class ProtocolV2Parser {
 				serverOption -> reqBuilder.addServerOption(serverOption),
 				agent -> reqBuilder.setAgent(agent));
 
-		if (line == PacketLineIn.END) {
+		if (PacketLineIn.isEnd(line)) {
 			return reqBuilder.build();
 		}
 
-		if (line != PacketLineIn.DELIM) {
+		if (!PacketLineIn.isDelimiter(line)) {
 			throw new PackProtocolException(
 					MessageFormat.format(JGitText.get().unexpectedPacketLine,
 							line));
@@ -244,11 +244,11 @@ final class ProtocolV2Parser {
 				serverOption -> builder.addServerOption(serverOption),
 				agent -> builder.setAgent(agent));
 
-		if (line == PacketLineIn.END) {
+		if (PacketLineIn.isEnd(line)) {
 			return builder.build();
 		}
 
-		if (line != PacketLineIn.DELIM) {
+		if (!PacketLineIn.isDelimiter(line)) {
 			throw new PackProtocolException(MessageFormat
 					.format(JGitText.get().unexpectedPacketLine, line));
 		}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/transport/ReceivePack.java b/org.eclipse.jgit/src/org/eclipse/jgit/transport/ReceivePack.java
index 4652c3fda8..d6adf1e0d8 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/transport/ReceivePack.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/transport/ReceivePack.java
@@ -348,7 +348,7 @@ public class ReceivePack extends BaseReceivePack {
 			pushOptions = new ArrayList<>(4);
 			for (;;) {
 				String option = in.readString();
-				if (option == PacketLineIn.END) {
+				if (PacketLineIn.isEnd(option)) {
 					break;
 				}
 				pushOptions.add(option);
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportHttp.java b/org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportHttp.java
index b752a65275..42aa80ea48 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportHttp.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportHttp.java
@@ -902,7 +902,7 @@ public class TransportHttp extends HttpTransport implements WalkTransport,
 					JGitText.get().expectedGot, exp, act));
 		}
 
-		while (pckIn.readString() != PacketLineIn.END) {
+		while (!PacketLineIn.isEnd(pckIn.readString())) {
 			// for now, ignore the remaining header lines
 		}
 	}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/transport/UploadPack.java b/org.eclipse.jgit/src/org/eclipse/jgit/transport/UploadPack.java
index 6217d2a0e9..9278f42adf 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/transport/UploadPack.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/transport/UploadPack.java
@@ -1229,7 +1229,7 @@ public class UploadPack {
 			/* EOF when awaiting command is fine */
 			return true;
 		}
-		if (command == PacketLineIn.END) {
+		if (PacketLineIn.isEnd(command)) {
 			// A blank request is valid according
 			// to the protocol; do nothing in this
 			// case.
@@ -1600,7 +1600,7 @@ public class UploadPack {
 				throw eof;
 			}
 
-			if (line == PacketLineIn.END) {
+			if (PacketLineIn.isEnd(line)) {
 				last = processHaveLines(peerHas, last, pckOut);
 				if (commonBase.isEmpty() || multiAck != MultiAck.OFF)
 					pckOut.writeString("NAK\n"); //$NON-NLS-1$