/**
* 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
* <p/>
* http://www.apache.org/licenses/LICENSE-2.0
* <p/>
* 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.superbiz.dynamicdatasourcerouting;
import org.apache.openejb.resource.jdbc.router.AbstractRouter;
import javax.naming.NamingException;
import javax.sql.DataSource;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
public class DeterminedRouter extends AbstractRouter {
private String dataSourceNames;
private String defaultDataSourceName;
private Map<String, DataSource> dataSources = null;
private ThreadLocal<DataSource> currentDataSource = new ThreadLocal<DataSource>();
/**
* @param datasourceList datasource resource name, separator is a space
*/
public void setDataSourceNames(String datasourceList) {
dataSourceNames = datasourceList;
}
/**
* lookup datasource in openejb resources
*/
private void init() {
dataSources = new ConcurrentHashMap<String, DataSource>();
for (String ds : dataSourceNames.split(" ")) {
try {
Object o = getOpenEJBResource(ds);
if (o instanceof DataSource) {
dataSources.put(ds, DataSource.class.cast(o));
}
} catch (NamingException e) {
// ignored
}
}
}
/**
* @return the user selected data source if it is set
* or the default one
* @throws IllegalArgumentException if the data source is not found
*/
@Override
public DataSource getDataSource() {
// lazy init of routed datasources
if (dataSources == null) {
init();
}
// if no datasource is selected use the default one
if (currentDataSource.get() == null) {
if (dataSources.containsKey(defaultDataSourceName)) {
return dataSources.get(defaultDataSourceName);
} else {
throw new IllegalArgumentException("you have to specify at least one datasource");
}
}
// the developper set the datasource to use
return currentDataSource.get();
}
/**
* @param datasourceName data source name
*/
public void setDataSource(String datasourceName) {
if (dataSources == null) {
init();
}
if (!dataSources.containsKey(datasourceName)) {
throw new IllegalArgumentException("data source called " + datasourceName + " can't be found.");
}
DataSource ds = dataSources.get(datasourceName);
currentDataSource.set(ds);
}
/**
* reset the data source
*/
public void clear() {
currentDataSource.remove();
}
public void setDefaultDataSourceName(String name) {
this.defaultDataSourceName = name;
}
}