Java API: BoostingQueryBuilder does not build the query correctly, closes #1141.

modules/elasticsearch/src/main/java/org/elasticsearch/index/query/BaseQueryBuilder.java

@@ -31,6 +31,17 @@ import java.io.IOException;
  */
 public abstract class BaseQueryBuilder implements QueryBuilder {
 
+    @Override public String toString() {
+        try {
+            XContentBuilder builder = XContentFactory.safeJsonBuilder();
+            builder.prettyPrint();
+            toXContent(builder, EMPTY_PARAMS);
+            return builder.string();
+        } catch (Exception e) {
+            throw new QueryBuilderException("Failed to build query", e);
+        }
+    }
+
     @Override public BytesStream buildAsUnsafeBytes() throws QueryBuilderException {
         return buildAsUnsafeBytes(XContentType.JSON);
     }

modules/elasticsearch/src/main/java/org/elasticsearch/index/query/BoostingQueryBuilder.java

@@ -90,5 +90,6 @@ public class BoostingQueryBuilder extends BaseQueryBuilder {
         if (boost != -1) {
             builder.field("boost", boost);
         }
+        builder.endObject();
     }
 }