Add ST_AsEWKB function

docs/CHANGELOG.md

@@ -3,4 +3,5 @@
 + Fix javadoc issues.
 + Remove `slf4j-simple` dependency (#1261)
 + Fix geometry_columns view function in order to escape table name with reserved database word (#1269)
-+  Change batch size to use the optimal size (#1275) 
++ Change batch size to use the optimal size (#1275) 
++ Add ST_AsEWKB function(#1271)

h2gis-functions/src/main/java/org/h2gis/functions/factory/H2GISFunctions.java

@@ -319,7 +319,8 @@ public static Function[] getBuiltInsFunctions() {
                 new ST_Force3DM(),
                 new ST_VariableBuffer(),
                 new ST_SubDivide(),
-                new ST_MemSize()
+                new ST_MemSize(),
+                new ST_AsEWKB()
         };
     }
 

h2gis-functions/src/main/java/org/h2gis/functions/spatial/convert/ST_AsEWKB.java

@@ -0,0 +1,61 @@
+/**
+ * H2GIS is a library that brings spatial support to the H2 Database Engine
+ * <http://www.h2database.com>. H2GIS is developed by CNRS
+ * <http://www.cnrs.fr/>.
+ *
+ * This code is part of the H2GIS project. H2GIS is free software; 
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * Lesser General Public License as published by the Free Software Foundation;
+ * version 3.0 of the License.
+ *
+ * H2GIS is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details <http://www.gnu.org/licenses/>.
+ *
+ *
+ * For more information, please consult: <http://www.h2gis.org/>
+ * or contact directly: info_at_h2gis.org
+ */
+
+package org.h2gis.functions.spatial.convert;
+
+import org.h2.util.geometry.JTSUtils;
+import org.h2.value.Value;
+import org.h2gis.api.DeterministicScalarFunction;
+import org.locationtech.jts.geom.Geometry;
+
+import java.sql.SQLException;
+
+/**
+ * Convert a Geometry value into an Extended Well-Known Binary.
+ * @author Nicolas Fortin
+ */
+public class ST_AsEWKB extends DeterministicScalarFunction {
+    /**
+     * Default constructor
+     */
+    public ST_AsEWKB() {
+        addProperty(PROP_REMARKS, "Convert a geometry into EWKB representation.");
+    }
+
+    @Override
+    public String getJavaStaticMethod() {
+        return "asEWKB";
+    }
+
+    /**
+     * Convert a Geometry value into an Extended Well-Known Binary.
+     * @param value Geometry instance
+     * @return The bytes representation
+     */
+    public static byte[] asEWKB(Value value) throws SQLException {
+        switch (value.getValueType()) {
+            case Value.NULL:
+            case Value.GEOMETRY:
+                return value.getBytes();
+            default:
+                throw new SQLException("ST_AsEWKB only supports geometry value");
+        }
+    }
+}

h2gis-functions/src/test/java/org/h2gis/functions/spatial/convert/GeometryConvertTest.java

@@ -0,0 +1,100 @@
+/**
+ * H2GIS is a library that brings spatial support to the H2 Database Engine
+ * <http://www.h2database.com>. H2GIS is developed by CNRS
+ * <http://www.cnrs.fr/>.
+ *
+ * This code is part of the H2GIS project. H2GIS is free software; 
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * Lesser General Public License as published by the Free Software Foundation;
+ * version 3.0 of the License.
+ *
+ * H2GIS is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details <http://www.gnu.org/licenses/>.
+ *
+ *
+ * For more information, please consult: <http://www.h2gis.org/>
+ * or contact directly: info_at_h2gis.org
+ */
+
+package org.h2gis.functions.spatial.convert;
+
+import org.h2gis.functions.factory.H2GISDBFactory;
+import org.h2gis.functions.factory.H2GISFunctions;
+import org.h2gis.functions.spatial.geometry.DummySpatialFunction;
+import org.h2gis.functions.spatial.geometry.GeometryFormsTest;
+import org.h2gis.unitTest.GeometryAsserts;
+import org.junit.jupiter.api.*;
+import org.locationtech.jts.geom.*;
+import org.locationtech.jts.geom.impl.CoordinateArraySequence;
+
+import java.sql.Connection;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+
+/**
+ * @author Sylvain Palominos
+ * @author Erwan Bocher
+ * 
+ */
+public class GeometryConvertTest {
+    private static final GeometryFactory FACTORY = new GeometryFactory();
+
+    private static Connection connection;
+    private Statement st;
+
+    @BeforeAll
+    public static void tearUp() throws Exception {
+        // Keep a connection alive to not close the DataBase on each unit test
+        connection = H2GISDBFactory.createSpatialDataBase(GeometryConvertTest.class.getSimpleName());
+    }
+
+    @AfterAll
+    public static void tearDown() throws Exception {
+        connection.close();
+    }
+
+    @BeforeEach
+    public void setUpStatement() throws Exception {
+        st = connection.createStatement();
+    }
+
+    @AfterEach
+    public void tearDownStatement() throws Exception {
+        st.close();
+    }
+
+    @Test
+    public void AsEWKB1() throws SQLException {
+        ResultSet rs = st.executeQuery("SELECT RAWTOHEX(ST_AsEWKB(ST_GeomFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))',4326)));");
+        rs.next();
+        assertEquals("0020000003000010e600000001000000050000000000000000000000000000000000000000000000003ff00000000000003ff00000000000003ff00000000000003ff0000000000000000000000000000000000000000000000000000000000000",  rs.getString(1));
+    }
+
+    @Test
+    public void AsEWKB2() throws SQLException {
+        ResultSet rs = st.executeQuery("SELECT RAWTOHEX(ST_AsEWKB(ST_GeomFromText('POINT M(1 2 3)',4326)));");
+        rs.next();
+        assertEquals("0060000001000010e63ff000000000000040000000000000004008000000000000",  rs.getString(1));
+    }
+
+    @Test
+    public void AsEWKB3() throws SQLException {
+        ResultSet rs = st.executeQuery("SELECT RAWTOHEX(ST_AsEWKB(ST_GeomFromText('POINT Z (1 2 3)',4326)));");
+        rs.next();
+        assertEquals("00a0000001000010e63ff000000000000040000000000000004008000000000000",  rs.getString(1));
+    }
+
+    @Test
+    public void AsEWKB4() throws SQLException {
+        ResultSet rs = st.executeQuery("SELECT RAWTOHEX(ST_AsEWKB(ST_GeomFromText('POINT ZM (1 2 3 4)',4326)));");
+        rs.next();
+        assertEquals("00e0000001000010e63ff0000000000000400000000000000040080000000000004010000000000000",  rs.getString(1));
+    }
+
+}