Fix 'always true' assertion

Use org.junit.Assert's assertNotEquals(String, Object, Object)
to check if two MD5 are different.

junit.framework.TestCase's assertNotSame(String, Object, Object)
compares arguments by reference and for String arguments, in most cases,
returns true even if both arguments are equal by value.

As we need a negative assertion (two MD5 are not equal),
junit.framework.TestCase doesn't fit the bill - it does provide
assertEquals() but not assertNotEquals().

Change-Id: I1ce6123d9102de963c92da88bea5e713ecdf44e6
Signed-off-by: Mykola Nikishov <mn@mn.com.ua>
diff --git a/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/ant/MirrorTaskTest.java b/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/ant/MirrorTaskTest.java
index 4ef74d2..3dcc9f8 100644
--- a/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/ant/MirrorTaskTest.java
+++ b/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/ant/MirrorTaskTest.java
@@ -10,6 +10,8 @@
  *******************************************************************************/
 package org.eclipse.equinox.p2.tests.ant;
 
+import static org.junit.Assert.assertNotEquals;
+
 import java.io.*;
 import java.net.URI;
 import java.net.URISyntaxException;
@@ -716,7 +718,7 @@
 		IArtifactDescriptor descriptor2 = PublisherHelper.createArtifactDescriptor(dupKey, baselineContentLocation);
 
 		assertEquals("Ensuring Descriptors are the same", descriptor1, descriptor2);
-		assertNotSame("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
+		assertNotEquals("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
 
 		//Setup make repositories
 		IArtifactRepository repo = null;
diff --git a/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/artifact/repository/CompositeArtifactRepositoryTest.java b/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/artifact/repository/CompositeArtifactRepositoryTest.java
index d9d8b1e..506408a 100644
--- a/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/artifact/repository/CompositeArtifactRepositoryTest.java
+++ b/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/artifact/repository/CompositeArtifactRepositoryTest.java
@@ -13,6 +13,7 @@
 import static org.eclipse.equinox.p2.tests.publisher.actions.StatusMatchers.errorStatus;
 import static org.eclipse.equinox.p2.tests.publisher.actions.StatusMatchers.statusWithMessageWhich;
 import static org.hamcrest.CoreMatchers.*;
+import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertThat;
 
 import java.io.*;
@@ -716,7 +717,7 @@
 		IArtifactDescriptor descriptor2 = PublisherHelper.createArtifactDescriptor(dupKey, artifact2);
 
 		assertEquals("Ensuring Descriptors are the same", descriptor1, descriptor2);
-		assertNotSame("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
+		assertNotEquals("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
 
 		//Setup make repositories
 		File repo1Location = getTestFolder(getUniqueString());
@@ -755,7 +756,7 @@
 		IArtifactDescriptor descriptor2 = PublisherHelper.createArtifactDescriptor(dupKey, artifact2);
 
 		assertEquals("Ensuring Descriptors are the same", descriptor1, descriptor2);
-		assertNotSame("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
+		assertNotEquals("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
 
 		//Setup make repositories
 		File repo1Location = getTestFolder(getUniqueString());
diff --git a/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/mirror/ArtifactMirrorApplicationTest.java b/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/mirror/ArtifactMirrorApplicationTest.java
index e0ace22..03453e2 100644
--- a/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/mirror/ArtifactMirrorApplicationTest.java
+++ b/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/mirror/ArtifactMirrorApplicationTest.java
@@ -11,6 +11,8 @@
  *******************************************************************************/
 package org.eclipse.equinox.p2.tests.mirror;
 
+import static org.junit.Assert.assertNotEquals;
+
 import java.io.*;
 import java.net.*;
 import java.util.*;
@@ -1076,7 +1078,7 @@
 		IArtifactDescriptor descriptor2 = PublisherHelper.createArtifactDescriptor(dupKey, artifact2);
 
 		assertEquals("Ensuring Descriptors are the same", descriptor1, descriptor2);
-		assertNotSame("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
+		assertNotEquals("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
 
 		//Setup make repositories
 		File repo1Location = getTestFolder(getUniqueString());
@@ -1130,7 +1132,7 @@
 		IArtifactDescriptor descriptor2 = PublisherHelper.createArtifactDescriptor(dupKey, baselineContentLocation);
 
 		assertEquals("Ensuring Descriptors are the same", descriptor1, descriptor2);
-		assertNotSame("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
+		assertNotEquals("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
 
 		//Setup make repositories
 		IArtifactRepository repo = null;
diff --git a/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/mirror/NewMirrorApplicationArtifactTest.java b/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/mirror/NewMirrorApplicationArtifactTest.java
index 6932820..0dedddc 100644
--- a/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/mirror/NewMirrorApplicationArtifactTest.java
+++ b/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/mirror/NewMirrorApplicationArtifactTest.java
@@ -11,6 +11,8 @@
  *******************************************************************************/
 package org.eclipse.equinox.p2.tests.mirror;
 
+import static org.junit.Assert.assertNotEquals;
+
 import java.io.*;
 import java.net.MalformedURLException;
 import java.net.URI;
@@ -1158,7 +1160,7 @@
 		IArtifactDescriptor descriptor2 = PublisherHelper.createArtifactDescriptor(dupKey, artifact2);
 
 		assertEquals("Ensuring Descriptors are the same", descriptor1, descriptor2);
-		assertNotSame("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
+		assertNotEquals("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
 
 		//Setup make repositories
 		File repo1Location = getTestFolder(getUniqueString());
@@ -1225,7 +1227,7 @@
 		IArtifactDescriptor descriptor2 = PublisherHelper.createArtifactDescriptor(dupKey, baselineContentLocation);
 
 		assertEquals("Ensuring Descriptors are the same", descriptor1, descriptor2);
-		assertNotSame("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
+		assertNotEquals("Ensuring MD5 values are different", descriptor1.getProperty(IArtifactDescriptor.DOWNLOAD_MD5), descriptor2.getProperty(IArtifactDescriptor.DOWNLOAD_MD5));
 
 		//Setup make repositories
 		IArtifactRepository repo = null;