org.springframework.jdbc.core.metadata.OracleTableMetaDataProvider Maven / Gradle / Ivy
/*
* Copyright 2002-2018 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
*
* https://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.lang.Nullable;
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 meta-data lookup. Also supports lookup of current schema
* using the {@code sys_context}.
*
* 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;
@Nullable
private final String defaultSchema;
/**
* Constructor used to initialize with provided database meta-data.
* @param databaseMetaData meta-data to be used
*/
public OracleTableMetaDataProvider(DatabaseMetaData databaseMetaData) throws SQLException {
this(databaseMetaData, false);
}
/**
* Constructor used to initialize with provided database meta-data.
* @param databaseMetaData meta-data to be used
* @param includeSynonyms whether to include synonyms
*/
public OracleTableMetaDataProvider(DatabaseMetaData databaseMetaData, boolean includeSynonyms)
throws SQLException {
super(databaseMetaData);
this.includeSynonyms = includeSynonyms;
this.defaultSchema = lookupDefaultSchema(databaseMetaData);
}
/*
* Oracle-based implementation for detecting the current schema.
*/
@Nullable
private static String lookupDefaultSchema(DatabaseMetaData databaseMetaData) {
try {
CallableStatement cstmt = null;
try {
Connection con = databaseMetaData.getConnection();
if (con == null) {
logger.debug("Cannot check default schema - no Connection from DatabaseMetaData");
return null;
}
cstmt = con.prepareCall("{? = call sys_context('USERENV', 'CURRENT_SCHEMA')}");
cstmt.registerOutParameter(1, Types.VARCHAR);
cstmt.execute();
return cstmt.getString(1);
}
finally {
if (cstmt != null) {
cstmt.close();
}
}
}
catch (SQLException ex) {
logger.debug("Exception encountered during default schema lookup", ex);
return null;
}
}
@Override
@Nullable
protected String getDefaultSchema() {
if (this.defaultSchema != null) {
return this.defaultSchema;
}
return super.getDefaultSchema();
}
@Override
public void initializeWithTableColumnMetaData(DatabaseMetaData databaseMetaData,
@Nullable String catalogName, @Nullable String schemaName, @Nullable String tableName)
throws SQLException {
if (!this.includeSynonyms) {
logger.debug("Defaulting to no synonyms in table meta-data lookup");
super.initializeWithTableColumnMetaData(databaseMetaData, catalogName, schemaName, tableName);
return;
}
Connection con = databaseMetaData.getConnection();
if (con == null) {
logger.info("Unable to include synonyms in table meta-data lookup - no Connection from DatabaseMetaData");
super.initializeWithTableColumnMetaData(databaseMetaData, catalogName, schemaName, tableName);
return;
}
try {
Class oracleConClass = con.getClass().getClassLoader().loadClass("oracle.jdbc.OracleConnection");
con = (Connection) con.unwrap(oracleConClass);
}
catch (ClassNotFoundException | SQLException ex) {
if (logger.isInfoEnabled()) {
logger.info("Unable to include synonyms in table meta-data lookup - no Oracle Connection: " + ex);
}
super.initializeWithTableColumnMetaData(databaseMetaData, catalogName, schemaName, tableName);
return;
}
logger.debug("Including synonyms in table meta-data lookup");
Method setIncludeSynonyms;
Boolean originalValueForIncludeSynonyms;
try {
Method getIncludeSynonyms = con.getClass().getMethod("getIncludeSynonyms");
ReflectionUtils.makeAccessible(getIncludeSynonyms);
originalValueForIncludeSynonyms = (Boolean) getIncludeSynonyms.invoke(con);
setIncludeSynonyms = con.getClass().getMethod("setIncludeSynonyms", boolean.class);
ReflectionUtils.makeAccessible(setIncludeSynonyms);
setIncludeSynonyms.invoke(con, Boolean.TRUE);
}
catch (Throwable ex) {
throw new InvalidDataAccessApiUsageException("Could not prepare Oracle Connection", ex);
}
super.initializeWithTableColumnMetaData(databaseMetaData, catalogName, schemaName, tableName);
try {
setIncludeSynonyms.invoke(con, originalValueForIncludeSynonyms);
}
catch (Throwable ex) {
throw new InvalidDataAccessApiUsageException("Could not reset Oracle Connection", ex);
}
}
}