diff --git a/lucene/core/src/java/org/apache/lucene/index/IndexWriterConfig.java b/lucene/core/src/java/org/apache/lucene/index/IndexWriterConfig.java
index c773326f29c..09b3b1fcf0c 100644
--- a/lucene/core/src/java/org/apache/lucene/index/IndexWriterConfig.java
+++ b/lucene/core/src/java/org/apache/lucene/index/IndexWriterConfig.java
@@ -288,6 +288,9 @@ public final class IndexWriterConfig extends LiveIndexWriterConfig implements Cl
    * Only takes effect when IndexWriter is first created.
    */
   public IndexWriterConfig setCodec(Codec codec) {
+    if (codec == null) {
+      throw new NullPointerException();
+    }
     this.codec = codec;
     return this;
   }
diff --git a/lucene/core/src/java/org/apache/lucene/index/LiveIndexWriterConfig.java b/lucene/core/src/java/org/apache/lucene/index/LiveIndexWriterConfig.java
index f7f63949f47..448715acc35 100755
--- a/lucene/core/src/java/org/apache/lucene/index/LiveIndexWriterConfig.java
+++ b/lucene/core/src/java/org/apache/lucene/index/LiveIndexWriterConfig.java
@@ -116,6 +116,9 @@ public class LiveIndexWriterConfig {
     writeLockTimeout = IndexWriterConfig.WRITE_LOCK_TIMEOUT;
     indexingChain = DocumentsWriterPerThread.defaultIndexingChain;
     codec = Codec.getDefault();
+    if (codec == null) {
+      throw new NullPointerException();
+    }
     infoStream = InfoStream.getDefault();
     mergePolicy = new TieredMergePolicy();
     flushPolicy = new FlushByRamOrCountsPolicy();
diff --git a/lucene/core/src/test/org/apache/lucene/codecs/perfield/TestPerFieldDocValuesFormat.java b/lucene/core/src/test/org/apache/lucene/codecs/perfield/TestPerFieldDocValuesFormat.java
index 254cea37e38..42fa2e951fa 100644
--- a/lucene/core/src/test/org/apache/lucene/codecs/perfield/TestPerFieldDocValuesFormat.java
+++ b/lucene/core/src/test/org/apache/lucene/codecs/perfield/TestPerFieldDocValuesFormat.java
@@ -55,8 +55,8 @@ public class TestPerFieldDocValuesFormat extends BaseDocValuesFormatTestCase {
   
   @Override
   public void setUp() throws Exception {
-    super.setUp();
     codec = new RandomCodec(new Random(random().nextLong()), Collections.<String>emptySet());
+    super.setUp();
   }
   
   @Override