/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 java.sql;
/**
* This class is an actual usage of the wrapper pattern for JDBC classes.
* Developers can get the delegate instance when the instance may be a proxy
* class.
*
* @since 1.6
*/
public interface Wrapper {
/**
* Returns an object that implements the given interface. If the caller is
* not a wrapper, a SQLException will be thrown.
*
* @param iface -
* the class that defines the interface
* @return - an object that implements the interface
* @throws SQLException -
* if there is no object implementing the specific interface
*/
<T> T unwrap(Class<T> iface) throws SQLException;
/**
* If the caller is a wrapper of the class or implements the given
* interface, the methods return false and vice versa.
*
* @param iface -
* the class that defines the interface
* @return - true if the instance implements the interface
* @throws SQLException -
* when an error occurs when judges the object
*/
boolean isWrapperFor(Class<?> iface) throws SQLException;
}