/*
* Copyright 2002-2007 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
*
* 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.springframework.jdbc.support.nativejdbc;
/**
* Simple implementation of the {@link NativeJdbcExtractor} interface.
* Assumes a pool that wraps Connection handles but not DatabaseMetaData:
* In this case, the underlying native Connection can be retrieved by simply
* calling <code>conHandle.getMetaData().getConnection()</code>.
* All other JDBC objects will be returned as passed in.
*
* <p>This extractor should work with any pool that does not wrap DatabaseMetaData,
* and will also work with any plain JDBC driver. Note that a pool can still wrap
* Statements, PreparedStatements, etc: The only requirement of this extractor is
* that <code>java.sql.DatabaseMetaData</code> does not get wrapped, returning the
* native Connection of the JDBC driver on <code>metaData.getConnection()</code>.
*
* <p>Customize this extractor by setting the "nativeConnectionNecessaryForXxx"
* flags accordingly: If Statements, PreparedStatements, and/or CallableStatements
* are wrapped by your pool, set the corresponding "nativeConnectionNecessaryForXxx"
* flags to "true". If none of the statement types is wrapped - or you solely need
* Connection unwrapping in the first place -, the defaults are fine.
*
* <p>SimpleNativeJdbcExtractor is a common choice for use with OracleLobHandler,
* which just needs Connection unwrapping via the
* {@link #getNativeConnectionFromStatement} method. This usage will work
* with almost any connection pool. Known to work are, for example:
* <ul>
* <li>Caucho Resin 2.1.x, 3.0.x
* <li>Sun Java System Application Server 8
* <li>Oracle OC4J 9.0.3, 9.0.4
* <li>C3P0 0.8.x
* <li>Jakarta Commons DBCP 1.0, 1.1, 1.2 (used in Tomcat 4.1.x, 5.0.x)
* <li>JBoss 3.2.x
* </ul>
*
* <p>For full usage with JdbcTemplate, i.e. to also provide Statement unwrapping:
* <ul>
* <li>Use a default SimpleNativeJdbcExtractor for Resin and SJSAS (no JDBC
* Statement objects are wrapped, therefore no special unwrapping is necessary).
* <li>Use a SimpleNativeJdbcExtractor with all "nativeConnectionNecessaryForXxx"
* flags set to "true" for OC4J and C3P0 (all JDBC Statement objects are wrapped,
* but none of the wrappers allow for unwrapping).
* <li>Use a CommonsDbcpNativeJdbcExtractor for Jakarta Commons DBCP respectively
* a JBossNativeJdbcExtractor for JBoss (all JDBC Statement objects are wrapped,
* but all of them can be extracted by casting to implementation classes).
* </ul>
*
* @author Juergen Hoeller
* @since 05.12.2003
* @see #setNativeConnectionNecessaryForNativeStatements
* @see #setNativeConnectionNecessaryForNativePreparedStatements
* @see #setNativeConnectionNecessaryForNativeCallableStatements
* @see Jdbc4NativeJdbcExtractor
* @see org.springframework.jdbc.core.JdbcTemplate#setNativeJdbcExtractor
* @see org.springframework.jdbc.support.lob.OracleLobHandler#setNativeJdbcExtractor
*/
public class SimpleNativeJdbcExtractor extends NativeJdbcExtractorAdapter {
private boolean nativeConnectionNecessaryForNativeStatements = false;
private boolean nativeConnectionNecessaryForNativePreparedStatements = false;
private boolean nativeConnectionNecessaryForNativeCallableStatements = false;
/**
* Set whether it is necessary to work on the native Connection to
* receive native Statements. Default is "false". If true, the Connection
* will be unwrapped first to create a Statement.
* <p>This makes sense if you need to work with native Statements from
* a pool that does not allow to extract the native JDBC objects from its
* wrappers but returns the native Connection on DatabaseMetaData.getConnection.
* <p>The standard SimpleNativeJdbcExtractor is unable to unwrap statements,
* so set this to true if your connection pool wraps Statements.
* @see java.sql.Connection#createStatement
* @see java.sql.DatabaseMetaData#getConnection
*/
public void setNativeConnectionNecessaryForNativeStatements(boolean nativeConnectionNecessaryForNativeStatements) {
this.nativeConnectionNecessaryForNativeStatements = nativeConnectionNecessaryForNativeStatements;
}
@Override
public boolean isNativeConnectionNecessaryForNativeStatements() {
return this.nativeConnectionNecessaryForNativeStatements;
}
/**
* Set whether it is necessary to work on the native Connection to
* receive native PreparedStatements. Default is "false". If true,
* the Connection will be unwrapped first to create a PreparedStatement.
* <p>This makes sense if you need to work with native PreparedStatements from
* a pool that does not allow to extract the native JDBC objects from its
* wrappers but returns the native Connection on Statement.getConnection.
* <p>The standard SimpleNativeJdbcExtractor is unable to unwrap statements,
* so set this to true if your connection pool wraps PreparedStatements.
* @see java.sql.Connection#prepareStatement
* @see java.sql.DatabaseMetaData#getConnection
*/
public void setNativeConnectionNecessaryForNativePreparedStatements(boolean nativeConnectionNecessary) {
this.nativeConnectionNecessaryForNativePreparedStatements = nativeConnectionNecessary;
}
@Override
public boolean isNativeConnectionNecessaryForNativePreparedStatements() {
return this.nativeConnectionNecessaryForNativePreparedStatements;
}
/**
* Set whether it is necessary to work on the native Connection to
* receive native CallableStatements. Default is "false". If true,
* the Connection will be unwrapped first to create a CallableStatement.
* <p>This makes sense if you need to work with native CallableStatements from
* a pool that does not allow to extract the native JDBC objects from its
* wrappers but returns the native Connection on Statement.getConnection.
* <p>The standard SimpleNativeJdbcExtractor is unable to unwrap statements,
* so set this to true if your connection pool wraps CallableStatements.
* @see java.sql.Connection#prepareCall
* @see java.sql.DatabaseMetaData#getConnection
*/
public void setNativeConnectionNecessaryForNativeCallableStatements(boolean nativeConnectionNecessary) {
this.nativeConnectionNecessaryForNativeCallableStatements = nativeConnectionNecessary;
}
@Override
public boolean isNativeConnectionNecessaryForNativeCallableStatements() {
return this.nativeConnectionNecessaryForNativeCallableStatements;
}
}
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