ST_MaxZ.java

package com.esri.hadoop.hive;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.io.BytesWritable;
// DoubleWritable - must use hive-serde2; the other one produces struct {value:d.d}
import org.apache.hadoop.hive.serde2.io.DoubleWritable;


import com.esri.core.geometry.ogc.OGCGeometry;

@Description(name = "ST_MaxZ",
   value = "_FUNC_(geometry) - returns the maximum Z coordinate of geometry",
   extended = "Example:\n"
   + "  SELECT _FUNC_(ST_PointZ(1.5, 2.5, 2)) FROM src LIMIT 1;  -- 2\n"
   + "  SELECT _FUNC_(ST_LineString('linestring z (1.5 2.5 2, 3.0 2.2 1)')) FROM src LIMIT 1;  -- 1\n"
)
//@HivePdkUnitTests(
//	cases = {
//		@HivePdkUnitTest(
//			query = "select ST_MaxZ(ST_PointZ(0., 3., 1.)) from onerow",
//			result = "1.0"
//			),
//		@HivePdkUnitTest(
//			query = "select ST_MaxZ(ST_GeomFromText('linestring z (10 10 2, 20 20 4)')) from onerow",
//			result = "4.0"
//			),
//		@HivePdkUnitTest(
//			query = "select ST_MaxZ(ST_MultiPoint('multipoint z((0 0 1), (2 2 3))')) from onerow",
//			result = "3.0"
//			),
//		@HivePdkUnitTest(
//			query = "select ST_MaxZ(ST_Point(1,2)) from onerow",
//			result = "null"
//			),
//		@HivePdkUnitTest(
//			query = "select ST_MaxZ(null) from onerow",
//			result = "null"
//			)
//	}
//)

public class ST_MaxZ extends ST_GeometryAccessor {
	final DoubleWritable resultDouble = new DoubleWritable();
	static final Log LOG = LogFactory.getLog(ST_MaxZ.class.getName());

	public DoubleWritable evaluate(BytesWritable geomref) {
		if (geomref == null || geomref.getLength() == 0) {
			LogUtils.Log_ArgumentsNull(LOG);
			return null;
		}

		OGCGeometry ogcGeometry = GeometryUtils.geometryFromEsriShape(geomref);
		if (ogcGeometry == null) {
			LogUtils.Log_ArgumentsNull(LOG);
			return null;
		}
		if (!ogcGeometry.is3D()) {
			LogUtils.Log_Not3D(LOG);
			return null;
		}

		resultDouble.set(ogcGeometry.MaxZ());
		return resultDouble;
	}

}