H2gisTest.java

package com.github.davidmoten.h2gis;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

import org.h2gis.h2spatialext.CreateSpatialExtension;
import org.junit.Test;

/**
 * Short demo of in memory spatial database.
 */
public class H2gisTest {

	@Test
	public void test() throws Exception {
		Class.forName("org.h2.Driver");
		// Open memory H2 table
		try (Connection connection = DriverManager.getConnection(
				"jdbc:h2:mem:syntax", "sa", "sa");
				Statement st = connection.createStatement()) {
			// Import spatial functions, domains and drivers
			// If you are using a file database, you have to do only that
			// once.
			CreateSpatialExtension.initSpatialExtension(connection);
			// Create a table
			st.execute("CREATE TABLE ROADS (the_geom MULTILINESTRING, speed_limit INT)");
			// Add some roads
			st.execute("INSERT INTO ROADS VALUES ('MULTILINESTRING((15 5, 20 6, 25 7))', 80)");
			st.execute("INSERT INTO ROADS VALUES ('MULTILINESTRING((20 6, 21 15, 21 25))', 50)");
			// Compute the sum of roads length
			try (ResultSet rs = st
					.executeQuery("SELECT SUM(ST_LENGTH(the_geom)) total_length from ROADS")) {
				if (rs.next()) {
					System.out.println("Total length of roads: "
							+ rs.getDouble("total_length") + " m");
				}
			}
		}
	}
}