[SOLR-2983] - fix custom merge policy instantiation issue in SolrIndexConfig

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1304098 13f79535-47bb-0310-9956-ffa450edef68

solr/CHANGES.txt

@@ -471,6 +471,10 @@ Documentation
 
 Upgrading from Solr 3.5
 ----------------------
+* SOLR-2983: As a consequence of moving the code which sets a MergePolicy from SolrIndexWriter to SolrIndexConfig,
+  (custom) MergePolicies should now have an empty constructor; thus an IndexWriter should not be passed as constructor
+  parameter but instead set using the setIndexWriter() method.
+
 * As doGet() methods in SimplePostTool was changed to static, the client applications of this
   class need to be recompiled.
 

solr/core/src/java/org/apache/solr/update/SolrIndexConfig.java

@@ -160,14 +160,9 @@ public class SolrIndexConfig {
   }
 
   private MergePolicy buildMergePolicy(IndexSchema schema) {
-    MergePolicy policy;
     String mpClassName = mergePolicyInfo == null ? defaultMergePolicyClassName : mergePolicyInfo.className;
 
-    try {
+    MergePolicy policy = (MergePolicy) schema.getResourceLoader().newInstance(mpClassName);
-      policy = (MergePolicy) schema.getResourceLoader().newInstance(mpClassName, null, new Class[]{IndexWriter.class}, new Object[]{this});
-    } catch (Exception e) {
-      policy = (MergePolicy) schema.getResourceLoader().newInstance(mpClassName);
-    }
 
     if (policy instanceof LogMergePolicy) {
       LogMergePolicy logMergePolicy = (LogMergePolicy) policy;

solr/core/src/test-files/solr/conf/bad-mp-solrconfig.xml

@@ -0,0 +1,51 @@
+<?xml version="1.0" ?>
+
+<!--
+ 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.
+-->
+
+<config>
+
+  <directoryFactory name="DirectoryFactory" class="${solr.directoryFactory:solr.RAMDirectoryFactory}"/>
+
+  <luceneMatchVersion>${tests.luceneMatchVersion:LUCENE_CURRENT}</luceneMatchVersion>
+
+  <indexDefaults>
+
+    <useCompoundFile>false</useCompoundFile>
+    <mergeFactor>10</mergeFactor>
+    <ramBufferSizeMB>32</ramBufferSizeMB>
+    <maxMergeDocs>2147483647</maxMergeDocs>
+    <maxFieldLength>10000</maxFieldLength>
+    <writeLockTimeout>1000</writeLockTimeout>
+    <mergePolicy class="org.apache.solr.update.DummyMergePolicy"/>
+
+  </indexDefaults>
+
+  <mainIndex>
+    <useCompoundFile>false</useCompoundFile>
+    <mergeFactor>8</mergeFactor>
+    <maxBufferedDocs>10</maxBufferedDocs>
+    <maxMergeDocs>2147483647</maxMergeDocs>
+    <maxFieldLength>10000</maxFieldLength>
+    <mergePolicy class="org.apache.solr.update.DummyMergePolicy"/>
+    <unlockOnStartup>true</unlockOnStartup>
+  </mainIndex>
+
+  <updateHandler class="solr.DirectUpdateHandler2"/>
+  <requestHandler name="standard" class="solr.StandardRequestHandler"></requestHandler>
+
+</config>

solr/core/src/test/org/apache/solr/update/DummyMergePolicy.java

@@ -0,0 +1,35 @@
+package org.apache.solr.update;
+
+/*
+ * 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 org.apache.lucene.index.IndexWriter;
+import org.apache.lucene.index.LogByteSizeMergePolicy;
+
+/**
+ * Dummy implementation of {@link org.apache.lucene.index.MergePolicy} which doesn't have an empty constructor and
+ * is expected to fail if used within Solr
+ */
+class DummyMergePolicy extends LogByteSizeMergePolicy {
+
+  private DummyMergePolicy() {}
+
+  public DummyMergePolicy(IndexWriter writer) {
+    super();
+    setIndexWriter(writer);
+  }
+}

solr/core/src/test/org/apache/solr/update/SolrIndexConfigTest.java

@@ -0,0 +1,53 @@
+package org.apache.solr.update;
+
+/*
+ * 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 org.apache.solr.SolrTestCaseJ4;
+import org.apache.solr.core.SolrConfig;
+import org.apache.solr.schema.IndexSchema;
+import org.junit.Test;
+
+/**
+ * Testcase for {@link SolrIndexConfig}
+ */
+public class SolrIndexConfigTest extends SolrTestCaseJ4 {
+
+  @Test
+  public void testFailingSolrIndexConfigCreation() {
+    try {
+      SolrConfig solrConfig = new SolrConfig("bad-mp-solrconfig.xml");
+      SolrIndexConfig solrIndexConfig = new SolrIndexConfig(solrConfig, null, null);
+      IndexSchema indexSchema = new IndexSchema(solrConfig, "schema.xml", null);
+      solrIndexConfig.toIndexWriterConfig(indexSchema);
+      fail("a mergePolicy should have an empty constructor in order to be instantiated in Solr thus this should fail ");
+    } catch (Exception e) {
+      // it failed as expected
+    }
+  }
+
+  @Test
+  public void testTieredMPSolrIndexConfigCreation() throws Exception {
+    SolrConfig solrConfig = new SolrConfig("solrconfig-mergepolicy.xml");
+    SolrIndexConfig solrIndexConfig = new SolrIndexConfig(solrConfig, null, null);
+    assertNotNull(solrIndexConfig);
+    assertEquals("org.apache.lucene.index.TieredMergePolicy", solrIndexConfig.defaultMergePolicyClassName);
+    IndexSchema indexSchema = new IndexSchema(solrConfig, "schema.xml", null);
+    solrIndexConfig.toIndexWriterConfig(indexSchema);
+  }
+
+}