/*
* Copyright 2002-2011 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.core.metadata;
import java.lang.reflect.Method;
import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.SQLException;
import java.sql.Types;
import org.springframework.dao.InvalidDataAccessApiUsageException;
import org.springframework.jdbc.support.nativejdbc.NativeJdbcExtractor;
import org.springframework.util.ReflectionUtils;
/**
* Oracle-specific implementation of the {@link org.springframework.jdbc.core.metadata.TableMetaDataProvider}.
* Supports a feature for including synonyms in the metadata lookup. Also supports lookup of current schema using
* the sys_context.
*
* <p>Thanks to Mike Youngstrom and Bruce Campbell for submitting the original suggestion for the Oracle
* current schema lookup implementation.
*
* @author Thomas Risberg
* @author Juergen Hoeller
* @since 3.0
*/
public class OracleTableMetaDataProvider extends GenericTableMetaDataProvider {
private final boolean includeSynonyms;
private String defaultSchema;
public OracleTableMetaDataProvider(DatabaseMetaData databaseMetaData) throws SQLException {
this(databaseMetaData, false);
}
public OracleTableMetaDataProvider(DatabaseMetaData databaseMetaData, boolean includeSynonyms) throws SQLException {
super(databaseMetaData);
this.includeSynonyms = includeSynonyms;
lookupDefaultSchema(databaseMetaData);
}
@Override
protected String getDefaultSchema() {
if (defaultSchema != null) {
return defaultSchema;
}
return super.getDefaultSchema();
}
@Override
public void initializeWithTableColumnMetaData(DatabaseMetaData databaseMetaData,
String catalogName, String schemaName, String tableName) throws SQLException {
if (!this.includeSynonyms) {
logger.debug("Defaulting to no synonyms in table metadata lookup");
super.initializeWithTableColumnMetaData(databaseMetaData, catalogName, schemaName, tableName);
return;
}
Connection con = databaseMetaData.getConnection();
NativeJdbcExtractor nativeJdbcExtractor = getNativeJdbcExtractor();
if (nativeJdbcExtractor != null) {
con = nativeJdbcExtractor.getNativeConnection(con);
}
boolean isOracleCon;
try {
Class<?> oracleConClass = getClass().getClassLoader().loadClass("oracle.jdbc.OracleConnection");
isOracleCon = oracleConClass.isInstance(con);
}
catch (ClassNotFoundException ex) {
if (logger.isInfoEnabled()) {
logger.info("Couldn't find Oracle JDBC API: " + ex);
}
isOracleCon = false;
}
if (!isOracleCon) {
logger.warn("Unable to include synonyms in table metadata lookup. Connection used for " +
"DatabaseMetaData is not recognized as an Oracle connection: " + con);
super.initializeWithTableColumnMetaData(databaseMetaData, catalogName, schemaName, tableName);
return;
}
logger.debug("Including synonyms in table metadata lookup");
Method setIncludeSynonyms;
Boolean originalValueForIncludeSynonyms;
try {
Method getIncludeSynonyms = con.getClass().getMethod("getIncludeSynonyms", (Class[]) null);
ReflectionUtils.makeAccessible(getIncludeSynonyms);
originalValueForIncludeSynonyms = (Boolean) getIncludeSynonyms.invoke(con);
setIncludeSynonyms = con.getClass().getMethod("setIncludeSynonyms", new Class[] {boolean.class});
ReflectionUtils.makeAccessible(setIncludeSynonyms);
setIncludeSynonyms.invoke(con, Boolean.TRUE);
}
catch (Exception ex) {
throw new InvalidDataAccessApiUsageException("Couldn't prepare Oracle Connection", ex);
}
super.initializeWithTableColumnMetaData(databaseMetaData, catalogName, schemaName, tableName);
try {
setIncludeSynonyms.invoke(con, originalValueForIncludeSynonyms);
}
catch (Exception ex) {
throw new InvalidDataAccessApiUsageException("Couldn't reset Oracle Connection", ex);
}
}
/*
* Oracle implementation for detecting current schema
*
* @param databaseMetaData
*/
private void lookupDefaultSchema(DatabaseMetaData databaseMetaData) {
try {
CallableStatement cstmt = null;
try {
cstmt = databaseMetaData.getConnection().prepareCall("{? = call sys_context('USERENV', 'CURRENT_SCHEMA')}");
cstmt.registerOutParameter(1, Types.VARCHAR);
cstmt.execute();
this.defaultSchema = cstmt.getString(1);
}
finally {
if (cstmt != null) {
cstmt.close();
}
}
} catch (Exception ignore) {}
}
}