correct licensing and incorporation of FastMath

this resolves incorrectly licensed code in elastic#49009.

ESSloppyMath is removed in favor of preserving as much of the original
FastMath as possible. Since no additional methods are introduced in
ESSloppyMath, this abstraction is removed.

libs/core/src/main/java/org/elasticsearch/common/util/ESSloppyMath.java → libs/core/src/main/java/org/elasticsearch/common/util/FastMath.java

@@ -1,10 +1,9 @@
 /*
- * 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
+ * Copyright 2012 Jeff Hain
+ *
+ * Licensed 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
  *
@@ -14,16 +13,11 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.elasticsearch.common.util;
 
 /*
  * =============================================================================
+ * Notice of fdlibm package this program is partially derived from:
  *
- * sinh and atan ported from
- * https://github.com/yannrichet/jmathplot/blob/f25426e0ab0e68647ad2b75f577c7be050ecac86/src/main/java/org/math/plot/utils/FastMath.java
- * (Apache 2.0) Copyright 2012 Jeff Hain, which is partially derived from fdlibm package
- *
- * =============================================================================
  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
  *
  * Developed at SunSoft, a Sun Microsystems, Inc. business.
@@ -33,13 +27,18 @@
  * =============================================================================
  */
 
-
-/**
- * Similar to Lucene's SloppyMath, but for additional math functions.
+/*
+ * This code sourced from:
+ * https://github.com/yannrichet/jmathplot/blob/f25426e0ab0e68647ad2b75f577c7be050ecac86/src/main/java/org/math/plot/utils/FastMath.java
  */
-public class ESSloppyMath {
 
-    private ESSloppyMath() {}
+package org.elasticsearch.common.util;
+
+public final class FastMath {
+
+    private FastMath() {
+
+    }
 
     //--------------------------------------------------------------------------
     // RE-USABLE CONSTANTS
@@ -177,4 +176,5 @@ public static double atan(double value) {
             }
         }
     }
+
 }

libs/core/src/test/java/org/elasticsearch/common/util/ESSloppyMathTests.java → libs/core/src/test/java/org/elasticsearch/common/util/FastMathTests.java

@@ -1,27 +1,30 @@
 /*
- * 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
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch 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
+ *    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.
+ * 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.
  */
+
 package org.elasticsearch.common.util;
 
 import org.elasticsearch.test.ESTestCase;
 
-import static org.elasticsearch.common.util.ESSloppyMath.atan;
-import static org.elasticsearch.common.util.ESSloppyMath.sinh;
+import static org.elasticsearch.common.util.FastMath.atan;
+import static org.elasticsearch.common.util.FastMath.sinh;
 
-public class ESSloppyMathTests extends ESTestCase {
+public class FastMathTests extends ESTestCase {
 
     // accuracy for atan(x)
     static double ATAN_DELTA = 1E-15;

server/src/main/java/org/elasticsearch/search/aggregations/bucket/geogrid/GeoTileUtils.java

@@ -20,7 +20,7 @@
 
 import org.elasticsearch.ElasticsearchParseException;
 import org.elasticsearch.common.geo.GeoPoint;
-import org.elasticsearch.common.util.ESSloppyMath;
+import org.elasticsearch.common.util.FastMath;
 import org.elasticsearch.common.xcontent.ObjectParser.ValueType;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.common.xcontent.support.XContentMapValues;
@@ -211,7 +211,7 @@ private static int validateZXY(int zoom, int xTile, int yTile) {
     private static GeoPoint zxyToGeoPoint(int zoom, int xTile, int yTile) {
         final int tiles = validateZXY(zoom, xTile, yTile);
         final double n = Math.PI - (2.0 * Math.PI * (yTile + 0.5)) / tiles;
-        final double lat = Math.toDegrees(ESSloppyMath.atan(ESSloppyMath.sinh(n)));
+        final double lat = Math.toDegrees(FastMath.atan(FastMath.sinh(n)));
         final double lon = ((xTile + 0.5) / tiles * 360.0) - 180;
         return new GeoPoint(lat, lon);
     }