/**
* Copyright (C) 2012-2013 Selventa, Inc.
*
* This file is part of the OpenBEL Framework.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* The OpenBEL Framework is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with the OpenBEL Framework. If not, see <http://www.gnu.org/licenses/>.
*
* Additional Terms under LGPL v3:
*
* This license does not authorize you and you are prohibited from using the
* name, trademarks, service marks, logos or similar indicia of Selventa, Inc.,
* or, in the discretion of other licensors or authors of the program, the
* name, trademarks, service marks, logos or similar indicia of such authors or
* licensors, in any marketing or advertising materials relating to your
* distribution of the program or any covered product. This restriction does
* not waive or limit your obligation to keep intact all copyright notices set
* forth in the program as delivered to you.
*
* If you distribute the program in whole or in part, or any modified version
* of the program, and you assume contractual liability to the recipient with
* respect to the program or modified version, then you will indemnify the
* authors and licensors of the program for any liabilities that these
* contractual assumptions directly impose on those licensors and authors.
*/
package org.openbel.framework.core.df;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Arrays;
import org.openbel.framework.common.InvalidArgument;
/**
* AbstractJdbcDataAccessor provides low-level JDBC operations for working
* with a database.
* <p>
* The {@link PreparedStatement} objects used are cached to avoid repeated
* statement compilation and increase application performance.
* </p>
*
* @author Anthony Bargnesi {@code <abargnesi@selventa.com>}
*/
public abstract class AbstractJdbcDAO {
public static final String SCHEMA_NAME_PLACEHOLDER = "@";
protected static final int DEFAULT_FETCH_SIZE = 100000;
protected DBConnection dbConnection = null;
protected final String schemaName;
/**
* Protected constructor created with a <tt>dbConnection</tt> and the
* <tt>schemaName</tt>.
*
* @param dbConnection {@link DBConnection}, the db connection, which
* cannot be null
* @param schemaName {@link String}, the schema name to use in
* SQL statements
* @throws SQLException Thrown if a database exception occurred
* while checking if the <tt>dbConnection</tt> is closed or if the
* <tt>dbConnection</tt> is no longer valid and cannot be re-established
* @throws InvalidArgument Thrown if the <tt>dbConnection</tt> argument
* is null or the <tt>schemaName</tt> is null
*/
protected AbstractJdbcDAO(final DBConnection dbConnection,
String schemaName) throws SQLException {
if (dbConnection == null) {
throw new InvalidArgument("dbConnection", dbConnection);
}
if (dbConnection.getConnection().isClosed()) {
throw new InvalidArgument("dbc is closed and cannot be used");
}
if (schemaName == null) {
throw new InvalidArgument("schemaName", dbConnection);
}
this.dbConnection = dbConnection;
this.schemaName = schemaName;
}
/**
* Closes the <tt>dbConnection</tt> associated with this instance.
*
* <p>
* This must be called before the instance goes out of scope.
* </p>
*/
public void terminate() {
dbConnection.close();
}
/**
* Returns the schema name associated with this JDBC dao.
*
* @return {@link String} schema name
*/
public final String getSchemaName() {
return schemaName;
}
/**
* Returns a {@link PreparedStatement} for the SQL statement in
* <tt>sql</tt>.
*
* @param sql {@link String}, the sql to prepare which can take certain
* placeholders:<ul>
* <il>? - paremeter substitution marker for the {@link PreparedStatement}</li>
* <il>@ - schema name substitution marker defined</li></ul>
* @return {@link PreparedStatement}
* @throws SQLException Thrown if a database exception occurred or if the
* <tt>dbConnection</tt> is no longer valid and cannot be re-established
*/
protected PreparedStatement getPreparedStatement(String sql)
throws SQLException {
// Inject the schema name into the SQL
String replacedSQL = injectSchema(sql);
return getPreparedStatement(replacedSQL, replacedSQL);
}
/**
* Returns a {@link PreparedStatement} for the SQL statement in <tt>sql</tt>
* providing a {@link ResultSet result set} of a given type and concurrency.
*
* @param sql {@link String}, the sql to prepare which can take certain
* placeholders:
* <ul>
* <il>? - paremeter substitution marker for the {@link PreparedStatement}
* </li> <il>@ - schema name substitution marker defined</li>
* </ul>
* @param type Result set type
* @param concurrency Result set concurrency
* @return {@link PreparedStatement}
* @throws SQLException Thrown if a database exception occurred or if the
* <tt>dbConnection</tt> is no longer valid and cannot be re-established
* @see ResultSet#TYPE_SCROLL_INSENSITIVE
* @see ResultSet#CONCUR_READ_ONLY
*/
protected PreparedStatement getPreparedStatement(String sql, int type,
int concurrency) throws SQLException {
// Inject the schema name into the SQL
String isql = injectSchema(sql);
return dbConnection.getPreparedStatement(isql, isql, type, concurrency);
}
/**
* Returns the {@link PreparedStatement} wrapping a sql statement in
* <tt>sql</tt>.
*
* <p>
* The prepared statement's <tt>autoGeneratedKeys</tt> feature is set via
* the additional parameter.
* </p>
*
* @param sql {@link String} the sql statement to use in the
* {@link PreparedStatement}, which can take parameter substitutions - '?'.
* @param autoGeneratedKeys <tt>int</tt> the auto generated keys feature
* in the {@link PreparedStatement}
* @return {@link PreparedStatement} the prepared statement, which could
* be either new or cached
* @throws SQLException Thrown if a database exception occurred or if the
* <tt>dbConnection</tt> is no longer valid and cannot be re-established
*/
protected PreparedStatement getPreparedStatement(String sql,
int autoGeneratedKeys) throws SQLException {
String replacedSQL = injectSchema(sql);
// use the auto generated key parameter as part of the key
return dbConnection.getPreparedStatement(replacedSQL, autoGeneratedKeys
+ replacedSQL, autoGeneratedKeys);
}
/**
* Returns the {@link PreparedStatement} for the sql statement defined by
* <tt>sql</tt> and that expects the columns defined in <tt>columnNames</tt>
* to be returned.
*
* @param sql {@link String}, the sql statement
* @param columnNames <tt>String[]</tt>, the columns names expected in the
* prepared statement's result set
* @return {@link PreparedStatement} the prepared statement for this sql
* statement
* @throws SQLException Thrown if a database exception occurred or if the
* <tt>dbConnection</tt> is no longer valid and cannot be re-established
*/
protected PreparedStatement getPreparedStatement(String sql,
String[] columnNames) throws SQLException {
String replacedSQL = injectSchema(sql);
return dbConnection.getPreparedStatement(replacedSQL,
Arrays.hashCode(columnNames)
+ replacedSQL, columnNames);
}
protected String injectSchema(String sql) {
return sql.replace(SCHEMA_NAME_PLACEHOLDER, schemaName);
}
private PreparedStatement getPreparedStatement(String sql, String key)
throws SQLException {
return dbConnection.getPreparedStatement(sql, key,
Statement.NO_GENERATED_KEYS);
}
/**
* Closes the {@link Statement}, swallowing any {@link SQLException}
* exceptions that occur.
*
* @param stmt {@link Statement} the statement to close
*/
protected void close(Statement stmt) {
if (null != stmt) {
try {
stmt.close();
} catch (SQLException e) {}
}
}
/**
* Closes the {@link ResultSet}, swallowing any {@link SQLException}
* exceptions that occur.
*
* @param rset {@link ResultSet} the result set to close
*/
protected void close(ResultSet rset) {
if (null != rset) {
try {
rset.close();
} catch (SQLException e) {}
}
}
/**
* Closes the {@link PreparedStatement}, swallowing any
* {@link SQLException} exceptions that occur.
*
* @param pstmt {@link PreparedStatement} the prepared statement to close
*/
protected void close(PreparedStatement pstmt) {
if (null != pstmt) {
try {
pstmt.close();
} catch (SQLException e) {
// swallowed
}
}
}
/**
* Closes the {@link Connection}, swallowing any {@link SQLException}
* exceptions that occur.
*
* @param c {@link Connection} the connection to close
*/
protected void close(Connection c) {
if (null != c) {
try {
c.close();
} catch (SQLException e) {
// swallowed
}
}
}
}