org.springframework.boot.jdbc.DataSourceUnwrapper Maven / Gradle / Ivy
/*
* Copyright 2012-2018 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.boot.jdbc;
import java.sql.Wrapper;
import javax.sql.DataSource;
import org.springframework.aop.framework.AopProxyUtils;
import org.springframework.aop.support.AopUtils;
import org.springframework.jdbc.datasource.DelegatingDataSource;
import org.springframework.util.ClassUtils;
/**
* Unwraps a {@link DataSource} that may have been proxied or wrapped in a custom
* {@link Wrapper} such as {@link DelegatingDataSource}.
*
* @author Tadaya Tsuyukubo
* @author Stephane Nicoll
* @since 2.0.7
*/
public final class DataSourceUnwrapper {
private static final boolean DELEGATING_DATA_SOURCE_PRESENT = ClassUtils.isPresent(
"org.springframework.jdbc.datasource.DelegatingDataSource",
DataSourceUnwrapper.class.getClassLoader());
private DataSourceUnwrapper() {
}
/**
* Return an object that implements the given {@code target} type, unwrapping delegate
* or proxy if necessary.
* @param dataSource the datasource to handle
* @param target the type that the result must implement
* @param the target type
* @return an object that implements the target type or {@code null}
*/
public static T unwrap(DataSource dataSource, Class target) {
if (target.isInstance(dataSource)) {
return target.cast(dataSource);
}
T unwrapped = safeUnwrap(dataSource, target);
if (unwrapped != null) {
return unwrapped;
}
if (DELEGATING_DATA_SOURCE_PRESENT) {
DataSource targetDataSource = DelegatingDataSourceUnwrapper
.getTargetDataSource(dataSource);
if (targetDataSource != null) {
return unwrap(targetDataSource, target);
}
}
if (AopUtils.isAopProxy(dataSource)) {
Object proxyTarget = AopProxyUtils.getSingletonTarget(dataSource);
if (proxyTarget instanceof DataSource) {
return unwrap((DataSource) proxyTarget, target);
}
}
return null;
}
private static S safeUnwrap(Wrapper wrapper, Class target) {
try {
return wrapper.unwrap(target);
}
catch (Exception ex) {
return null;
}
}
private static class DelegatingDataSourceUnwrapper {
private static DataSource getTargetDataSource(DataSource dataSource) {
if (dataSource instanceof DelegatingDataSource) {
return ((DelegatingDataSource) dataSource).getTargetDataSource();
}
return null;
}
}
}