西峡微网站开发,网站导航菜单兰,网站 廉政建设 板块,中关村在线对比文章目录 springboot启动初始化ddl过程如何自定义修改 table springboot启动初始化ddl过程
跟踪Springboot整合hibernate的启动代码#xff1a; SessionFactoryImpl 的初始化里做了非常多的事情#xff0c;初始化各种资源#xff0c;并调用 SchemaManagementToolCoordinat… 文章目录 springboot启动初始化ddl过程如何自定义修改 table springboot启动初始化ddl过程
跟踪Springboot整合hibernate的启动代码 SessionFactoryImpl 的初始化里做了非常多的事情初始化各种资源并调用 SchemaManagementToolCoordinator.process 先执行脚本任务再执行 Db任务 performScriptAction( actions.getScriptAction(), metadata, tool, serviceRegistry, executionOptions, configService );performDatabaseAction( actions.getDatabaseAction(), metadata, tool, serviceRegistry, executionOptions ); 在这里就开始进行 spring.jpa.hibernate.ddl-auto 配置的项进行处理了。 在 doMigration 时就获取到 tables 的元数据
public class GroupedSchemaMigratorImpl extends AbstractSchemaMigrator {public GroupedSchemaMigratorImpl(HibernateSchemaManagementTool tool, SchemaFilter schemaFilter) {super(tool, schemaFilter);}protected NameSpaceTablesInformation performTablesMigration(Metadata metadata, DatabaseInformation existingDatabase, ExecutionOptions options, Dialect dialect, Formatter formatter, SetString exportIdentifiers, boolean tryToCreateCatalogs, boolean tryToCreateSchemas, SetIdentifier exportedCatalogs, Namespace namespace, GenerationTarget[] targets) {NameSpaceTablesInformation tablesInformation new NameSpaceTablesInformation(metadata.getDatabase().getJdbcEnvironment().getIdentifierHelper());if (this.schemaFilter.includeNamespace(namespace)) {this.createSchemaAndCatalog(existingDatabase, options, dialect, formatter, tryToCreateCatalogs, tryToCreateSchemas, exportedCatalogs, namespace, targets);NameSpaceTablesInformation tables existingDatabase.getTablesInformation(namespace);Iterator var14 namespace.getTables().iterator();Table table;TableInformation tableInformation;while(var14.hasNext()) {table (Table)var14.next();if (this.schemaFilter.includeTable(table) table.isPhysicalTable()) {this.checkExportIdentifier(table, exportIdentifiers);tableInformation tables.getTableInformation(table);if (tableInformation null) {this.createTable(table, dialect, metadata, formatter, options, targets);} else if (tableInformation ! null tableInformation.isPhysicalTable()) {tablesInformation.addTableInformation(tableInformation);this.migrateTable(table, tableInformation, dialect, metadata, formatter, options, targets);}}}var14 namespace.getTables().iterator();while(true) {do {do {do {if (!var14.hasNext()) {return tablesInformation;}table (Table)var14.next();} while(!this.schemaFilter.includeTable(table));} while(!table.isPhysicalTable());tableInformation tablesInformation.getTableInformation(table);} while(tableInformation ! null (tableInformation null || !tableInformation.isPhysicalTable()));this.applyIndexes(table, tableInformation, dialect, metadata, formatter, options, targets);this.applyUniqueKeys(table, tableInformation, dialect, metadata, formatter, options, targets);}} else {return tablesInformation;}}
}如何自定义修改 table
再往下的过程到 HibernateSchemaManagementTool 这个核心类 ddl-auto 语义的实现就在这里。 那要自定义修改 table 最常见的需要就是 hibernate 只能增加对于修改字段长度这一类的涉及不到。当然这种修改只限于开发技术交流生产环境慎用。 回归正题要想修改字段长度有这么几个关键数据
table 的元数据Entity 的元数据 hibernate 本身的功能如 Migrator 既然能识别到字段缺失那肯定也能获取到这2个元数据。也就是2个参数registry 和 metadata。 了解了需要的数据就有了思路
public void migrateDB(DataSourceProperties dataSource, EntityManager entityManager, String ddlAuto, String dialectStr) {log.info(schema 生成{}, dataSource.getUrl());SetEntityType? entities entityManager.getMetamodel().getEntities();Properties p new Properties();// 数据库方言最终输出的方言p.put(AvailableSettings.DIALECT, dialectStr);// 自动执行的动作p.put(AvailableSettings.HBM2DDL_AUTO, ddlAuto);// 分隔符默认为空p.put(AvailableSettings.HBM2DDL_DELIMITER, ;);// 是否展示SQLp.put(AvailableSettings.SHOW_SQL, true);p.put(hibernate.connection.driver_class, dataSource.getDriverClassName());p.put(hibernate.connection.url, dataSource.getUrl());p.put(hibernate.connection.username, dataSource.getUsername());p.put(hibernate.connection.password, dataSource.getPassword());// 是否使用默认的jdbc元数据默认为true读取项目自身的元数据p.put(hibernate.temp.use_jdbc_metadata_defaults, true);
// p.put(hibernate.temp.use_jdbc_metadata_defaults, false);ConfigurationHelper.resolvePlaceHolders(p);try (ServiceRegistry registry new StandardServiceRegistryBuilder().applySettings(p).build()) {Map settings registry.getService(ConfigurationService.class).getSettings();MetadataSources metadataSources new MetadataSources(registry);entities.forEach(entityType - metadataSources.addAnnotatedClass(entityType.getJavaType()));Metadata metadata metadataSources.buildMetadata();HashMap properties new HashMap();properties.putAll(registry.getService(ConfigurationService.class).getSettings());log.info(开始migration);SchemaManagementToolCoordinator.process(metadata, registry, settings, null);log.info(开始alter migration);SchemaAlterTool schemaAlterTool new SchemaAlterTool(registry);schemaAlterTool.performTablesAlter(registry, metadata);}}public void migrateDB(String jdbcUrl, DataSourceProperties dataSource, SetEntityType? entities, String ddlAuto) {log.info(schema 生成{}, jdbcUrl);Properties p new Properties();// 数据库方言最终输出的方言p.put(AvailableSettings.DIALECT, MySQL5InnoDBDialect.class.getName());// 自动执行的动作p.put(AvailableSettings.HBM2DDL_AUTO, ddlAuto);// 分隔符默认为空p.put(AvailableSettings.HBM2DDL_DELIMITER, ;);// 是否展示SQLp.put(AvailableSettings.SHOW_SQL, true);p.put(hibernate.connection.driver_class, dataSource.getDriverClassName());p.put(hibernate.connection.url, jdbcUrl);p.put(hibernate.connection.username, dataSource.getUsername());p.put(hibernate.connection.password, dataSource.getPassword());// 是否使用默认的jdbc元数据默认为true读取项目自身的元数据p.put(hibernate.temp.use_jdbc_metadata_defaults, true);
// p.put(hibernate.temp.use_jdbc_metadata_defaults, false);ConfigurationHelper.resolvePlaceHolders(p);try (ServiceRegistry registry new StandardServiceRegistryBuilder().applySettings(p).build()) {Map settings registry.getService(ConfigurationService.class).getSettings();MetadataSources metadataSources new MetadataSources(registry);entities.forEach(entityType - metadataSources.addAnnotatedClass(entityType.getJavaType()));Metadata metadata metadataSources.buildMetadata();HashMap properties new HashMap();properties.putAll(registry.getService(ConfigurationService.class).getSettings());log.info(开始migration);SchemaManagementToolCoordinator.process(metadata, registry, settings, null);log.info(开始alter migration);SchemaAlterTool schemaAlterTool new SchemaAlterTool(registry);schemaAlterTool.performTablesAlter(registry, metadata);}}自定义 hibernate 的entity 关联 table
public class SchemaAlterTool {private Logger log LoggerFactory.getLogger(SchemaAlterTool.class);protected SchemaFilter schemaFilter;ServiceRegistry registry;private HibernateSchemaManagementTool tool;private JdbcContext jdbcContext;public SchemaAlterTool(ServiceRegistry registry) {this.registry registry;SchemaFilterProvider schemaFilterProvider registry.getService(StrategySelector.class).resolveDefaultableStrategy(SchemaFilterProvider.class,null,DefaultSchemaFilterProvider.INSTANCE);this.schemaFilter schemaFilterProvider.getMigrateFilter();}protected void validateColumnType(Table table, Column column, ColumnInformation columnInformation, Metadata metadata, Dialect dialect) {boolean typesMatch column.getSqlTypeCode(metadata) columnInformation.getTypeCode() || column.getSqlType(dialect, metadata).toLowerCase(Locale.ROOT).startsWith(columnInformation.getTypeName().toLowerCase(Locale.ROOT));if (!typesMatch) {throw new SchemaManagementException(String.format(Schema-alter: wrong column type encountered in column [%s] in table [%s]; found [%s (Types#%s)], but expecting [%s (Types#%s)], column.getName(), table.getQualifiedTableName(), columnInformation.getTypeName().toLowerCase(Locale.ROOT), JdbcTypeNameMapper.getTypeName(columnInformation.getTypeCode()), column.getSqlType().toLowerCase(Locale.ROOT), JdbcTypeNameMapper.getTypeName(column.getSqlTypeCode(metadata))));}}/*** param column 模型信息* param columnInformation 数据库信息* return*/protected boolean validateColumnLength(Column column, ColumnInformation columnInformation, Metadata metadata, Dialect dialect) {Value value column.getValue();String name value.getType().getName();if (!string.equals(name)) {return true;}
// 255 默认值忽略if (column.getLength() 255) {return true;}
// boolean typesMatch column.getSqlTypeCode(metadata) columnInformation.getTypeCode() || column.getSqlType(dialect, metadata).toLowerCase(Locale.ROOT).startsWith(columnInformation.getTypeName().toLowerCase(Locale.ROOT));
// if (!typesMatch) {
// return true;
// }if (column.getSqlType(dialect, metadata).toLowerCase(Locale.ROOT).startsWith(clob)) {return true;}
// columnInformation.getTypeName()
// 有大佬定义 columnDefinationString sqlType column.getSqlType();if (!StringUtils.isEmpty(sqlType) sqlType.length() 24) {return true;}if (!(column.getLength() columnInformation.getColumnSize())) {log.info(column {} not match length {}, column.getName(), column.getLength());return false;}return true;}public NameSpaceTablesInformation performTablesAlter(ServiceRegistry registry, Metadata metadata) {tool (HibernateSchemaManagementTool) registry.getService(SchemaManagementTool.class);Map configurationValues registry.getService(ConfigurationService.class).getSettings();ExecutionOptions options new ExecutionOptions() {Overridepublic boolean shouldManageNamespaces() {return true;}Overridepublic Map getConfigurationValues() {return configurationValues;}Overridepublic ExceptionHandler getExceptionHandler() {return ExceptionHandlerLoggedImpl.INSTANCE;}};NameSpaceTablesInformation tablesInformation new NameSpaceTablesInformation(metadata.getDatabase().getJdbcEnvironment().getIdentifierHelper());jdbcContext tool.resolveJdbcContext(options.getConfigurationValues());final DdlTransactionIsolator isolator tool.getDdlTransactionIsolator(jdbcContext);final DatabaseInformation databaseInformation Helper.buildDatabaseInformation(tool.getServiceRegistry(),isolator,metadata.getDatabase().getDefaultNamespace().getName());try {for (Namespace namespace : metadata.getDatabase().getNamespaces()) {if (schemaFilter.includeNamespace(namespace)) {alterTables(metadata, databaseInformation, options, jdbcContext.getDialect(), namespace);}}} finally {try {databaseInformation.cleanup();} catch (Exception e) {log.debug(Problem releasing DatabaseInformation : e.getMessage());}isolator.release();}return tablesInformation;}protected void alterTables(Metadata metadata, DatabaseInformation databaseInformation, ExecutionOptions options, Dialect dialect, Namespace namespace) {NameSpaceTablesInformation tables databaseInformation.getTablesInformation(namespace);Iterator tableIter namespace.getTables().iterator();while (tableIter.hasNext()) {Table table (Table) tableIter.next();if (this.schemaFilter.includeTable(table) table.isPhysicalTable()) {this.alterTable(table, tables.getTableInformation(table), metadata, options, dialect);}}}protected void alterTable(Table table, TableInformation tableInformation, Metadata metadata, ExecutionOptions options, Dialect dialect) {if (tableInformation null) {throw new SchemaManagementException(String.format(Schema-alter: missing table [%s], table.getQualifiedTableName().toString()));} else {Iterator selectableItr table.getColumnIterator();while (selectableItr.hasNext()) {Selectable selectable (Selectable) selectableItr.next();if (Column.class.isInstance(selectable)) {Column column (Column) selectable;ColumnInformation existingColumn tableInformation.getColumn(Identifier.toIdentifier(column.getQuotedName()));if (existingColumn null) {throw new SchemaManagementException(String.format(Schema-alter: missing column [%s] in table [%s], column.getName(), table.getQualifiedTableName()));}
// this.validateColumnType(table, column, existingColumn, metadata, dialect);if (!validateColumnLength(column, existingColumn, metadata, dialect)) {log.info(table alter:{}, table.getQualifiedTableName());boolean format Helper.interpretFormattingEnabled(options.getConfigurationValues());Formatter formatter format ? FormatStyle.DDL.getFormatter() : FormatStyle.NONE.getFormatter();final GenerationTarget[] targets new GenerationTarget[]{new GenerationTargetToDatabase(tool.getDdlTransactionIsolator(jdbcContext), true)};migrateTable(table, column, tableInformation, dialect, metadata, formatter, options, targets);}}}}}protected void migrateTable(Table table, Column column, TableInformation tableInformation, Dialect dialect, Metadata metadata, Formatter formatter, ExecutionOptions options, GenerationTarget... targets) {Database database metadata.getDatabase();AlterTable alterTable new AlterTable(table);applySqlStrings(false, alterTable.sqlAlterStrings(dialect, metadata, tableInformation,column,database.getDefaultNamespace().getPhysicalName().getCatalog(),database.getDefaultNamespace().getPhysicalName().getSchema()),formatter,options,targets);for (int i 0; i targets.length; i) {targets[i].release();}}void applySqlStrings(boolean quiet, Iterator sqlStrings, Formatter formatter, ExecutionOptions options, GenerationTarget... targets) {if (sqlStrings ! null) {while (sqlStrings.hasNext()) {String sqlString (String) sqlStrings.next();applySqlString(quiet, sqlString, formatter, options, targets);}}}private static void applySqlString(boolean quiet, String sqlString, Formatter formatter, ExecutionOptions options, GenerationTarget... targets) {if (!StringHelper.isEmpty(sqlString)) {String sqlStringFormatted formatter.format(sqlString);GenerationTarget[] exeProcessor targets;int excCount targets.length;for (int i 0; i excCount; i) {GenerationTarget target exeProcessor[i];try {target.accept(sqlStringFormatted);} catch (CommandAcceptanceException var11) {if (!quiet) {options.getExceptionHandler().handleException(var11);}}}}}
}
