Java tutorial
/* * Copyright 2012-2019 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 * * https://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.autoconfigure.jdbc; import java.util.ArrayList; import java.util.Collections; import java.util.List; import javax.sql.DataSource; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.boot.context.properties.source.InvalidConfigurationPropertyValueException; import org.springframework.boot.jdbc.DataSourceBuilder; import org.springframework.boot.jdbc.DataSourceInitializationMode; import org.springframework.boot.jdbc.EmbeddedDatabaseConnection; import org.springframework.core.io.DefaultResourceLoader; import org.springframework.core.io.Resource; import org.springframework.core.io.ResourceLoader; import org.springframework.jdbc.config.SortedResourcesFactoryBean; import org.springframework.jdbc.datasource.init.DatabasePopulatorUtils; import org.springframework.jdbc.datasource.init.ResourceDatabasePopulator; import org.springframework.util.StringUtils; /** * Initialize a {@link DataSource} based on a matching {@link DataSourceProperties} * config. * * @author Dave Syer * @author Phillip Webb * @author Edd Melndez * @author Stephane Nicoll * @author Kazuki Shimizu */ class DataSourceInitializer { private static final Log logger = LogFactory.getLog(DataSourceInitializer.class); private final DataSource dataSource; private final DataSourceProperties properties; private final ResourceLoader resourceLoader; /** * Create a new instance with the {@link DataSource} to initialize and its matching * {@link DataSourceProperties configuration}. * @param dataSource the datasource to initialize * @param properties the matching configuration * @param resourceLoader the resource loader to use (can be null) */ DataSourceInitializer(DataSource dataSource, DataSourceProperties properties, ResourceLoader resourceLoader) { this.dataSource = dataSource; this.properties = properties; this.resourceLoader = (resourceLoader != null) ? resourceLoader : new DefaultResourceLoader(); } /** * Create a new instance with the {@link DataSource} to initialize and its matching * {@link DataSourceProperties configuration}. * @param dataSource the datasource to initialize * @param properties the matching configuration */ DataSourceInitializer(DataSource dataSource, DataSourceProperties properties) { this(dataSource, properties, null); } DataSource getDataSource() { return this.dataSource; } /** * Create the schema if necessary. * @return {@code true} if the schema was created * @see DataSourceProperties#getSchema() */ boolean createSchema() { List<Resource> scripts = getScripts("spring.datasource.schema", this.properties.getSchema(), "schema"); if (!scripts.isEmpty()) { if (!isEnabled()) { logger.debug("Initialization disabled (not running DDL scripts)"); return false; } String username = this.properties.getSchemaUsername(); String password = this.properties.getSchemaPassword(); runScripts(scripts, username, password); } return !scripts.isEmpty(); } /** * Initialize the schema if necessary. * @see DataSourceProperties#getData() */ void initSchema() { List<Resource> scripts = getScripts("spring.datasource.data", this.properties.getData(), "data"); if (!scripts.isEmpty()) { if (!isEnabled()) { logger.debug("Initialization disabled (not running data scripts)"); return; } String username = this.properties.getDataUsername(); String password = this.properties.getDataPassword(); runScripts(scripts, username, password); } } private boolean isEnabled() { DataSourceInitializationMode mode = this.properties.getInitializationMode(); if (mode == DataSourceInitializationMode.NEVER) { return false; } if (mode == DataSourceInitializationMode.EMBEDDED && !isEmbedded()) { return false; } return true; } private boolean isEmbedded() { try { return EmbeddedDatabaseConnection.isEmbedded(this.dataSource); } catch (Exception ex) { logger.debug("Could not determine if datasource is embedded", ex); return false; } } private List<Resource> getScripts(String propertyName, List<String> resources, String fallback) { if (resources != null) { return getResources(propertyName, resources, true); } String platform = this.properties.getPlatform(); List<String> fallbackResources = new ArrayList<>(); fallbackResources.add("classpath*:" + fallback + "-" + platform + ".sql"); fallbackResources.add("classpath*:" + fallback + ".sql"); return getResources(propertyName, fallbackResources, false); } private List<Resource> getResources(String propertyName, List<String> locations, boolean validate) { List<Resource> resources = new ArrayList<>(); for (String location : locations) { for (Resource resource : doGetResources(location)) { if (resource.exists()) { resources.add(resource); } else if (validate) { throw new InvalidConfigurationPropertyValueException(propertyName, resource, "The specified resource does not exist."); } } } return resources; } private Resource[] doGetResources(String location) { try { SortedResourcesFactoryBean factory = new SortedResourcesFactoryBean(this.resourceLoader, Collections.singletonList(location)); factory.afterPropertiesSet(); return factory.getObject(); } catch (Exception ex) { throw new IllegalStateException("Unable to load resources from " + location, ex); } } private void runScripts(List<Resource> resources, String username, String password) { if (resources.isEmpty()) { return; } ResourceDatabasePopulator populator = new ResourceDatabasePopulator(); populator.setContinueOnError(this.properties.isContinueOnError()); populator.setSeparator(this.properties.getSeparator()); if (this.properties.getSqlScriptEncoding() != null) { populator.setSqlScriptEncoding(this.properties.getSqlScriptEncoding().name()); } for (Resource resource : resources) { populator.addScript(resource); } DataSource dataSource = this.dataSource; if (StringUtils.hasText(username) && StringUtils.hasText(password)) { dataSource = DataSourceBuilder.create(this.properties.getClassLoader()) .driverClassName(this.properties.determineDriverClassName()).url(this.properties.determineUrl()) .username(username).password(password).build(); } DatabasePopulatorUtils.execute(populator, dataSource); } }