Java tutorial
/* * Copyright 2012-2017 the original author or authors. * * 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 * * 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.springframework.boot.jdbc; import java.io.Closeable; import java.io.IOException; import java.net.URL; import java.net.URLClassLoader; import java.util.Arrays; import javax.sql.DataSource; import com.zaxxer.hikari.HikariDataSource; import org.apache.commons.dbcp2.BasicDataSource; import org.junit.After; import org.junit.Test; import static org.assertj.core.api.Assertions.assertThat; /** * Tests for {@link DataSourceBuilder}. * * @author Stephane Nicoll */ public class DataSourceBuilderTests { private DataSource dataSource; @After public void shutdownDataSource() throws IOException { if (this.dataSource instanceof Closeable) { ((Closeable) this.dataSource).close(); } } @Test public void defaultToHikari() { this.dataSource = DataSourceBuilder.create().url("jdbc:h2:test").build(); assertThat(this.dataSource).isInstanceOf(HikariDataSource.class); } @Test public void defaultToTomcatIfHikariIsNotAvailable() { this.dataSource = DataSourceBuilder.create(new HidePackagesClassLoader("com.zaxxer.hikari")) .url("jdbc:h2:test").build(); assertThat(this.dataSource).isInstanceOf(org.apache.tomcat.jdbc.pool.DataSource.class); } @Test public void defaultToCommonsDbcp2AsLastResort() { this.dataSource = DataSourceBuilder .create(new HidePackagesClassLoader("com.zaxxer.hikari", "org.apache.tomcat.jdbc.pool")) .url("jdbc:h2:test").build(); assertThat(this.dataSource).isInstanceOf(BasicDataSource.class); } @Test public void specificTypeOfDataSource() { HikariDataSource hikariDataSource = DataSourceBuilder.create().type(HikariDataSource.class).build(); assertThat(hikariDataSource).isInstanceOf(HikariDataSource.class); } final class HidePackagesClassLoader extends URLClassLoader { private final String[] hiddenPackages; HidePackagesClassLoader(String... hiddenPackages) { super(new URL[0], HidePackagesClassLoader.class.getClassLoader()); this.hiddenPackages = hiddenPackages; } @Override protected Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundException { if (Arrays.stream(this.hiddenPackages).anyMatch(name::startsWith)) { throw new ClassNotFoundException(); } return super.loadClass(name, resolve); } } }