environment.java

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//$Id: Environment.java,v 1.18.2.26 2004/02/04 18:56:45 oneovthafew Exp $
package net.sf.hibernate.cfg;

import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.Statement;
import java.sql.Timestamp;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Properties;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import net.sf.hibernate.util.PropertiesHelper;


/**
 * Provides access to configuration info passed in <tt>Properties</tt> objects.
 * <br><br>
 * Hibernate has two property scopes:
 * <ul>
 * <li><b>Factory-level</b> properties may be passed to the <tt>SessionFactory</tt> when it
 * instantiated. Each instance might have different property values. If no
 * properties are specified, the factory calls <tt>Environment.getProperties()</tt>.
 * <li><b>System-level</b> properties are shared by all factory instances and are always
 * determined by the <tt>Environment</tt> properties.
 * </ul>
 * The only system-level properties are
 * <ul>
 * <li><tt>hibernate.jdbc.use_streams_for_binary</tt>
 * <li><tt>hibernate.cglib.use_reflection_optimizer</tt>
 * </ul>
 * <tt>Environment</tt> properties are populated by calling <tt>System.getProperties()</tt>
 * and then from a resource named <tt>/hibernate.properties</tt> if it exists. System
 * properties override properties specified in <tt>hibernate.properties</tt>.<br>
 * <br>
 * The <tt>SessionFactory</tt> is controlled by the following properties.
 * Properties may be either be <tt>System</tt> properties, properties
 * defined in a resource named <tt>/hibernate.properties</tt> or an instance of 
 * <tt>java.util.Properties</tt> passed to
 * <tt>Configuration.buildSessionFactory()</tt><br>
 * <br>
 * <table>
 * <tr><td><b>property</b></td><td><b>meaning</b></td></tr>
 * <tr>
 *   <td><tt>hibernate.dialect</tt></td>
 *   <td>classname of <tt>net.sf.hibernate.dialect.Dialect</tt> subclass</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.cache.provider_class</tt></td>
 *   <td>classname of <tt>net.sf.hibernate.cache.CacheProvider</tt>
 *   subclass (if not specified JCS is used)</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.connection.provider_class</tt></td>
 *   <td>classname of <tt>net.sf.hibernate.connection.ConnectionProvider</tt>
 *   subclass (if not specified hueristics are used)</td>
 * </tr>
 * <tr><td><tt>hibernate.connection.username</tt></td><td>database username</td></tr>
 * <tr><td><tt>hibernate.connection.password</tt></td><td>database password</td></tr>
 * <tr>
 *   <td><tt>hibernate.connection.url</tt></td>
 *   <td>JDBC URL (when using <tt>java.sql.DriverManager</tt>)</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.connection.driver_class</tt></td>
 *   <td>classname of JDBC driver</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.connection.isolation</tt></td>
 *   <td>JDBC transaction isolation level (only when using
 *     <tt>java.sql.DriverManager</tt>)
 *   </td>
 * </tr>
 *   <td><tt>hibernate.connection.pool_size</tt></td>
 *   <td>the maximum size of the connection pool (only when using
 *     <tt>java.sql.DriverManager</tt>)
 *   </td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.connection.datasource</tt></td>
 *   <td>databasource JNDI name (when using <tt>javax.sql.Datasource</tt>)</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.jndi.url</tt></td><td>JNDI <tt>InitialContext</tt> URL</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.jndi.class</tt></td><td>JNDI <tt>InitialContext</tt> classname</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.max_fetch_depth</tt></td>
 *   <td>maximum depth of outer join fetching</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.jdbc.batch_size</tt></td>
 *   <td>enable use of JDBC2 batch API for drivers which support it</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.jdbc.fetch_size</tt></td>
 *   <td>set the JDBC fetch size</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.jdbc.use_scrollable_resultset</tt></td>
 *   <td>enable use of JDBC2 scrollable resultsets (you only need this specify
 *   this property when using user supplied connections)</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.jdbc.use_getGeneratedKeys</tt></td>
 *   <td>enable use of JDBC3 PreparedStatement.getGeneratedKeys() to retrieve 
 *   natively generated keys after insert. Requires JDBC3+ driver and JRE1.4+</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.hbm2ddl.auto</tt></td>
 *   <td>enable auto DDL export</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.default_schema</tt></td>
 *   <td>use given schema name for unqualified tables (always optional)</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.session_factory_name</tt></td>
 *   <td>If set, the factory attempts to bind this name to itself in the
 *   JNDI context. This name is also used to support cross JVM <tt>
 *   Session</tt> (de)serialization.</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.transaction.manager_lookup_class</tt></td>
 *   <td>classname of <tt>net.sf.hibernate.transaction.TransactionManagerLookup</tt>
 *   implementor</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.transaction.factory_class</tt></td>
 *   <td>the factory to use for instantiating <tt>Transaction</tt>s.
 *   (Defaults to <tt>JDBCTransactionFactory</tt>.)</td>
 * </tr>
 * <tr>
 *   <td><tt>hibernate.query.substitutions</tt></td><td>query language token substitutions</td>
 * </tr>
 * </table>
 *
 * @see net.sf.hibernate.SessionFactory
 * @author Gavin King
 */
public final class Environment {
	
	public static final String VERSION = "2.1.2";
	
	/**
	 * <tt>ConnectionProvider</tt> implementor to use when obtaining connections
	 */
	public static final String CONNECTION_PROVIDER ="hibernate.connection.provider_class";
	/**
	 * JDBC driver class
	 */
	public static final String DRIVER ="hibernate.connection.driver_class";
	/**
	 * JDBC transaction isolation level
	 */
	public static final String ISOLATION ="hibernate.connection.isolation";
	/**
	 * JDBC URL
	 */
	public static final String URL ="hibernate.connection.url";
	/**
	 * JDBC user
	 */
	public static final String USER ="hibernate.connection.username";
	/**
	 * JDBC password
	 */
	public static final String PASS ="hibernate.connection.password";
	/**
	 * Maximum number of inactive connections for Hibernate's connection pool
	 */
	public static final String POOL_SIZE ="hibernate.connection.pool_size";
	/**
	 * <tt>java.sql.Datasource</tt> JNDI name
	 */
	public static final String DATASOURCE ="hibernate.connection.datasource";
	/**
	 * prefix for arbitrary JDBC connection properties
	 */
	public static final String CONNECTION_PREFIX = "hibernate.connection";
	
	/**
	 * Maximum size for Hibernate's statement cache
	 * 
	 * @deprecated Hibernate no longer has a built-in prepared statement cache
	 */
	public static final String STATEMENT_CACHE_SIZE ="hibernate.statement_cache.size";
	
	/**
	 * JNDI initial context class, <tt>Context.INITIAL_CONTEXT_FACTORY</tt>
	 */
	public static final String JNDI_CLASS ="hibernate.jndi.class";
	/**
	 * JNDI provider URL, <tt>Context.PROVIDER_URL</tt>
	 */
	public static final String JNDI_URL ="hibernate.jndi.url";
	/**
	 * prefix for arbitrary JNDI <tt>InitialContext</tt> properties
	 */
	public static final String JNDI_PREFIX = "hibernate.jndi";
	/**
	 * JNDI name to bind to <tt>SessionFactory</tt>
	 */
	public static final String SESSION_FACTORY_NAME = "hibernate.session_factory_name";
	
	/**
	 * Hibernate SQL <tt>Dialect</tt> class
	 */
	public static final String DIALECT ="hibernate.dialect";
	/**
	 * A default database schema (owner) name to use for unqualified tablenames
	 */
	public static final String DEFAULT_SCHEMA = "hibernate.default_schema";
	
	/**
	 * Enable logging of generated SQL to the console
	 */
	public static final String SHOW_SQL ="hibernate.show_sql";
	/**
	 * Enable deep fetching using outerjoins
	 * @deprecated use <tt>hibernate.max_fetch_depth=0</tt>
	 */
	public static final String USE_OUTER_JOIN ="hibernate.use_outer_join";
	/**
	 * Maximum depth of outerjoin fetching
	 */
	public static final String MAX_FETCH_DEPTH = "hibernate.max_fetch_depth";
	/**
	 * Use <tt>java.io</tt> streams to read / write binary data from / to JDBC
	 */
	public static final String USE_STREAMS_FOR_BINARY = "hibernate.jdbc.use_streams_for_binary";
	/**
	 * Use JDBC scrollable <tt>ResultSet</tt>s. This property is only necessary when there is
	 * no <tt>ConnectionProvider</tt>, ie. the user is supplying JDBC connections.
	 */
	public static final String USE_SCROLLABLE_RESULTSET = "hibernate.jdbc.use_scrollable_resultset";
	/**
	 * Gives the JDBC driver a hint as to the number of rows that should be fetched from the database
	 * when more rows are needed. If <tt>0</tt>, JDBC driver default settings will be used.
	 */
	public static final String USE_GET_GENERATED_KEYS = "hibernate.jdbc.use_get_generated_keys";
	/**
	 * Tells the JDBC driver to attempt to retrieve row Id with the JDBC 3.0 PreparedStatement.getGeneratedKeys()
	 * method. In general, performance will be better if this property is set to true and the underlying 
	 * JDBC driver supports getGeneratedKeys().
	 */
	public static final String STATEMENT_FETCH_SIZE = "hibernate.jdbc.fetch_size";
	/**
	 * Maximum JDBC batch size. A nonzero value enables batch updates.
	 */
	public static final String STATEMENT_BATCH_SIZE = "hibernate.jdbc.batch_size";
	
	/**
	 * An XSLT resource used to generate "custom" XML
	 */
	public static final String OUTPUT_STYLESHEET ="hibernate.xml.output_stylesheet";
	
	/**
	 * Maximum size of C3P0 connection pool
	 */
	public static final String C3P0_MAX_SIZE = "hibernate.c3p0.max_size";
	/**
	 * Minimum size of C3P0 connection pool
	 */
	public static final String C3P0_MIN_SIZE = "hibernate.c3p0.min_size";
	/**
	 * Maximum idle time for C3P0 connection pool
	 */
	public static final String C3P0_TIMEOUT = "hibernate.c3p0.timeout";
	/**
	 * Maximum size of C3P0 statement cache
	 */
	public static final String C3P0_MAX_STATEMENTS = "hibernate.c3p0.max_statements";
	/**
	 * Number of connections acquired when pool is exhausted
	 */
	public static final String C3P0_ACQUIRE_INCREMENT = "hibernate.c3p0.acquire_increment";
	/**
	 * Idle time before a C3P0 pooled connection is validated
	 */
	public static final String C3P0_IDLE_TEST_PERIOD = "hibernate.c3p0.idle_test_period";
	/**
	 * Should we validate the connection on checkout.
	 * @deprecated use <tt>C3P0_IDLE_TEST_PERIOD</tt>
	 */
	public static final String C3P0_VALIDATE_CONNECTION = "hibernate.c3p0.validate";
	
	/**
	 * Maximum number of checked out connections for DBCP connection pool
	 */
	public static final String DBCP_MAXACTIVE = "hibernate.dbcp.maxActive";
	/**
	 * Maximum number of idle connections for DBCP connection pool
	 */
	public static final String DBCP_MAXIDLE = "hibernate.dbcp.maxIdle";
	/**
	 * Maximum idle time for connections in DBCP connection pool (ms)
	 */
	public static final String DBCP_MAXWAIT = "hibernate.dbcp.maxWait";
	/**
	 * Action to take in case of an exhausted DBCP connection pool ( 0 = fail, 1 = block, 2= grow)
	 */
	public static final String DBCP_WHENEXHAUSTED = "hibernate.dbcp.whenExhaustedAction";
	/**
	 * Validate connection when borrowing connection from pool (optional, true or false)
	 */
	public static final String DBCP_VALIDATION_ONBORROW = "hibernate.dbcp.testOnBorrow";