org.hibernate.engine.jdbc.SerializableNClobProxy Maven / Gradle / Ivy
/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2009 by Red Hat Inc and/or its affiliates or by
* third-party contributors as indicated by either @author tags or express
* copyright attribution statements applied by the authors. All
* third-party contributions are distributed under license by Red Hat Inc.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package org.hibernate.engine.jdbc;
import java.sql.Clob;
import java.lang.reflect.Proxy;
/**
* Manages aspects of proxying java.sql.NClobs to add serializability.
*
* @author Steve Ebersole
*/
public class SerializableNClobProxy extends SerializableClobProxy {
private static final Class NCLOB_CLASS = loadNClobClassIfAvailable();
private static Class loadNClobClassIfAvailable() {
try {
return getProxyClassLoader().loadClass( "java.sql.NClob" );
}
catch ( ClassNotFoundException e ) {
return null;
}
}
private static final Class[] PROXY_INTERFACES = new Class[] { determineNClobInterface(), WrappedClob.class };
private static Class determineNClobInterface() {
// java.sql.NClob is a simple marker interface extending java.sql.Clob. So if java.sql.NClob is not available
// on the classloader, just use java.sql.Clob
return NCLOB_CLASS == null ? Clob.class : NCLOB_CLASS;
}
public static boolean isNClob(Clob clob) {
return NCLOB_CLASS != null && NCLOB_CLASS.isInstance( clob );
}
/**
* Builds a serializable {@link java.sql.Clob} wrapper around the given {@link java.sql.Clob}.
*
* @param clob The {@link java.sql.Clob} to be wrapped.
*
* @see #generateProxy(java.sql.Clob)
*/
protected SerializableNClobProxy(Clob clob) {
super( clob );
}
/**
* Generates a SerializableClobProxy proxy wrapping the provided Clob object.
*
* @param clob The Clob to wrap.
* @return The generated proxy.
*/
public static Clob generateProxy(Clob clob) {
return ( Clob ) Proxy.newProxyInstance(
getProxyClassLoader(),
PROXY_INTERFACES,
new SerializableNClobProxy( clob )
);
}
/**
* Determines the appropriate class loader to which the generated proxy
* should be scoped.
*
* @return The class loader appropriate for proxy construction.
*/
public static ClassLoader getProxyClassLoader() {
return SerializableClobProxy.getProxyClassLoader();
}
}