LUCENE-2385: TestNoDeletionPolicy was not added to version control. sorry !

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@932131 13f79535-47bb-0310-9956-ffa450edef68

lucene/src/test/org/apache/lucene/index/TestNoDeletionPolicy.java

@@ -0,0 +1,93 @@
+package org.apache.lucene.index;
+
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import static org.junit.Assert.*;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+import java.util.Arrays;
+
+import org.apache.lucene.analysis.WhitespaceAnalyzer;
+import org.apache.lucene.document.Document;
+import org.apache.lucene.document.Field;
+import org.apache.lucene.document.Field.Index;
+import org.apache.lucene.document.Field.Store;
+import org.apache.lucene.store.Directory;
+import org.apache.lucene.store.RAMDirectory;
+import org.apache.lucene.util.LuceneTestCaseJ4;
+import org.junit.Test;
+
+public class TestNoDeletionPolicy extends LuceneTestCaseJ4 {
+
+  @Test
+  public void testNoDeletionPolicy() throws Exception {
+    IndexDeletionPolicy idp = NoDeletionPolicy.INSTANCE;
+    idp.onInit(null);
+    idp.onCommit(null);
+  }
+
+  @Test
+  public void testFinalSingleton() throws Exception {
+    assertTrue(Modifier.isFinal(NoDeletionPolicy.class.getModifiers()));
+    Constructor<?>[] ctors = NoDeletionPolicy.class.getDeclaredConstructors();
+    assertEquals("expected 1 private ctor only: " + Arrays.toString(ctors), 1, ctors.length);
+    assertTrue("that 1 should be private: " + ctors[0], Modifier.isPrivate(ctors[0].getModifiers()));
+  }
+
+  @Test
+  public void testMethodsOverridden() throws Exception {
+    // Ensures that all methods of IndexDeletionPolicy are
+    // overridden/implemented. That's important to ensure that NoDeletionPolicy 
+    // overrides everything, so that no unexpected behavior/error occurs.
+    // NOTE: even though IndexDeletionPolicy is an interface today, and so all
+    // methods must be implemented by NoDeletionPolicy, this test is important
+    // in case one day IDP becomes an abstract class.
+    for (Method m : NoDeletionPolicy.class.getMethods()) {
+      // getDeclaredMethods() returns just those methods that are declared on
+      // NoDeletionPolicy. getMethods() returns those that are visible in that
+      // context, including ones from Object. So just filter out Object. If in
+      // the future IndexDeletionPolicy will become a class that extends a
+      // different class than Object, this will need to change.
+      if (m.getDeclaringClass() != Object.class) {
+        assertTrue(m + " is not overridden !", m.getDeclaringClass() == NoDeletionPolicy.class);
+      }
+    }
+  }
+
+  @Test
+  public void testAllCommitsRemain() throws Exception {
+    Directory dir = new RAMDirectory();
+    IndexWriter writer = new IndexWriter(dir, new IndexWriterConfig(
+        TEST_VERSION_CURRENT, new WhitespaceAnalyzer(TEST_VERSION_CURRENT))
+        .setIndexDeletionPolicy(NoDeletionPolicy.INSTANCE));
+    for (int i = 0; i < 10; i++) {
+      Document doc = new Document();
+      doc.add(new Field("c", "a" + i, Store.YES, Index.ANALYZED));
+      writer.addDocument(doc);
+      writer.commit();
+      // the reason to expect i + 2 commits is because when IndexWriter is
+      // created it creates a first commit. If this ever changes, then the
+      // expected should be i + 1 (and this comment removed).
+      assertEquals("wrong number of commits !", i + 2, IndexReader.listCommits(dir).size());
+    }
+    writer.close();
+  }
+  
+}