org.flywaydb.core.internal.dbsupport.DbSupport Maven / Gradle / Ivy
/**
* Copyright 2010-2016 Boxfuse GmbH
*
* 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.flywaydb.core.internal.dbsupport;
import org.flywaydb.core.api.FlywayException;
import java.sql.Connection;
import java.sql.SQLException;
/**
* Abstraction for database-specific functionality.
*/
public abstract class DbSupport {
/**
* The JDBC template available for use.
*/
protected final JdbcTemplate jdbcTemplate;
/**
* The original schema of the connection that should be restored later.
*/
protected final String originalSchema;
/**
* Creates a new DbSupport instance with this JdbcTemplate.
*
* @param jdbcTemplate The JDBC template to use.
*/
public DbSupport(JdbcTemplate jdbcTemplate) {
this.jdbcTemplate = jdbcTemplate;
this.originalSchema = jdbcTemplate.getConnection() == null ? null : getCurrentSchemaName();
}
/**
* @return The DB-specific JdbcTemplate instance.
*/
public JdbcTemplate getJdbcTemplate() {
return jdbcTemplate;
}
/**
* Retrieves the schema with this name in the database.
*
* @param name The name of the schema.
* @return The schema.
*/
public abstract Schema getSchema(String name);
/**
* Creates a new SqlStatementBuilder for this specific database.
*
* @return The new SqlStatementBuilder.
*/
public abstract SqlStatementBuilder createSqlStatementBuilder();
/**
* @return The name of the db.
*/
public abstract String getDbName();
/**
* Retrieves the original schema of the connection.
*
* @return The original schema for this connection.
*/
public Schema getOriginalSchema() {
if (originalSchema == null) {
return null;
}
return getSchema(originalSchema);
}
/**
* Retrieves the current schema.
*
* @return The current schema for this connection.
*/
public String getCurrentSchemaName() {
try {
return doGetCurrentSchemaName();
} catch (SQLException e) {
throw new FlywayException("Unable to retrieve the current schema for the connection", e);
}
}
/**
* Retrieves the current schema.
*
* @return The current schema for this connection.
* @throws SQLException when the current schema could not be retrieved.
*/
protected abstract String doGetCurrentSchemaName() throws SQLException;
/**
* Sets the current schema to this schema.
*
* @param schema The new current schema for this connection.
*/
public void changeCurrentSchemaTo(Schema schema) {
if (schema.getName().equals(originalSchema) || !schema.exists()) {
return;
}
try {
doChangeCurrentSchemaTo(schema.toString());
} catch (SQLException e) {
throw new FlywayException("Error setting current schema to " + schema, e);
}
}
/**
* Restores the current schema of the connection to its original setting.
*/
public void restoreCurrentSchema() {
try {
doChangeCurrentSchemaTo(originalSchema);
} catch (SQLException e) {
throw new FlywayException("Error restoring current schema to its original setting", e);
}
}
/**
* Sets the current schema to this schema.
*
* @param schema The new current schema for this connection.
* @throws SQLException when the current schema could not be set.
*/
protected abstract void doChangeCurrentSchemaTo(String schema) throws SQLException;
/**
* @return The database function that returns the current user.
*/
public abstract String getCurrentUserFunction();
/**
* Checks whether ddl transactions are supported by this database.
*
* @return {@code true} if ddl transactions are supported, {@code false} if not.
*/
public abstract boolean supportsDdlTransactions();
/**
* @return The representation of the value {@code true} in a boolean column.
*/
public abstract String getBooleanTrue();
/**
* @return The representation of the value {@code false} in a boolean column.
*/
public abstract String getBooleanFalse();
/**
* Quote these identifiers for use in sql queries. Multiple identifiers will be quoted and separated by a dot.
*
* @param identifiers The identifiers to quote.
* @return The fully qualified quoted identifiers.
*/
public String quote(String... identifiers) {
String result = "";
boolean first = true;
for (String identifier : identifiers) {
if (!first) {
result += ".";
}
first = false;
result += doQuote(identifier);
}
return result;
}
/**
* Quote this identifier for use in sql queries.
*
* @param identifier The identifier to quote.
* @return The fully qualified quoted identifier.
*/
protected abstract String doQuote(String identifier);
/**
* @return {@code true} if this database use a catalog to represent a schema. {@code false} if a schema is simply a schema.
*/
public abstract boolean catalogIsSchema();
/**
* Executes this COPY statement (PostgreSQL only).
*
* @param connection The connection to use.
* @param sql The statement to execute.
*/
public void executePgCopy(Connection connection, String sql) throws SQLException {
// Do nothing by default
}
}