Bug 500273 - Removing elements from source lookup cache not workingY20160908-1000Y20160901-1000I20160906-0800I20160830-0800

properly

Applied patch from  Alexander Schwarz and added test for the LRU cache.

Change-Id: I145af345d019a7f1414e7b97d1802891948ccf91
Signed-off-by: Andrey Loskutov <loskutov@gmx.de>

1 files changed, 48 insertions, 1 deletions

diff --git a/org.eclipse.debug.tests/src/org/eclipse/debug/tests/sourcelookup/SourceLookupFacilityTests.java b/org.eclipse.debug.tests/src/org/eclipse/debug/tests/sourcelookup/SourceLookupFacilityTests.java
index 9e474edd1..693f81b0e 100644
--- a/org.eclipse.debug.tests/src/org/eclipse/debug/tests/sourcelookup/SourceLookupFacilityTests.java
+++ b/org.eclipse.debug.tests/src/org/eclipse/debug/tests/sourcelookup/SourceLookupFacilityTests.java
@@ -10,12 +10,17 @@
  *******************************************************************************/
 package org.eclipse.debug.tests.sourcelookup;
 
-import junit.framework.TestCase;
+import java.lang.reflect.Field;
+import java.util.HashMap;
+import java.util.LinkedHashMap;
 
 import org.eclipse.debug.core.model.IStackFrame;
 import org.eclipse.debug.internal.ui.sourcelookup.SourceLookupFacility;
+import org.eclipse.debug.internal.ui.sourcelookup.SourceLookupResult;
 import org.eclipse.debug.ui.sourcelookup.ISourceLookupResult;
 
+import junit.framework.TestCase;
+
 /**
  * Tests {@link SourceLookupFacility}
  *
@@ -289,4 +294,46 @@ public class SourceLookupFacilityTests extends TestCase {
 			SourceLookupFacility.shutdown();
 		}
 	}
+
+	public void testLRU() throws Exception {
+		try {
+			final int MAX_LRU_SIZE = 10;
+
+			// Get the original map
+			Field field = SourceLookupFacility.class.getDeclaredField("fLookupResults"); //$NON-NLS-1$
+			field.setAccessible(true);
+			HashMap<?, ?> map = (HashMap<?, ?>) field.get(null);
+			LinkedHashMap<String, ISourceLookupResult> cached = new LinkedHashMap<>();
+
+			// fill the LRU with one element overflow
+			for (int i = 0; i < MAX_LRU_SIZE + 1; i++) {
+				String artifact = "" + i; //$NON-NLS-1$
+				ISourceLookupResult result = SourceLookupFacility.getDefault().lookup(artifact, fTestLocator, false);
+				assertNotNull("There should be a result", result); //$NON-NLS-1$
+				assertFalse(cached.containsKey(result));
+				cached.put(artifact, result);
+
+				result = SourceLookupFacility.getDefault().lookup(artifact, fTestLocator, false);
+				assertTrue(cached.containsValue(result));
+				assertTrue(map.size() <= MAX_LRU_SIZE);
+			}
+			assertEquals(MAX_LRU_SIZE, map.size());
+
+
+			// The LRU cache is full now, and the very first element should be
+			// *not* in the LRU cache anymore
+			assertFalse(map.containsValue(cached.values().iterator().next()));
+
+			// If we lookup for the first element again, we should get new one
+			String artifact = "" + 0; //$NON-NLS-1$
+			SourceLookupResult result = SourceLookupFacility.getDefault().lookup(artifact, fTestLocator, false);
+			assertNotNull("There should be a result", result); //$NON-NLS-1$
+			assertFalse(cached.containsValue(result));
+
+			// Check: the LRU map size should not grow
+			assertEquals(MAX_LRU_SIZE, map.size());
+		} finally {
+			SourceLookupFacility.shutdown();
+		}
+	}
 }