| /* |
| * Copyright (c) 2011, Rickard Öberg. All Rights Reserved. |
| * Copyright (c) 2012, Paul Merlin. All Rights Reserved. |
| * |
| * 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 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 org.qi4j.library.sql.datasource; |
| |
| import java.lang.reflect.InvocationHandler; |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.lang.reflect.Proxy; |
| import java.net.ConnectException; |
| import javax.sql.DataSource; |
| import org.qi4j.api.service.ServiceImporterException; |
| import org.qi4j.functional.Specification; |
| import org.qi4j.library.circuitbreaker.CircuitBreaker; |
| |
| import static org.qi4j.functional.Specifications.not; |
| import static org.qi4j.library.circuitbreaker.CircuitBreakers.in; |
| import static org.qi4j.library.circuitbreaker.CircuitBreakers.rootCause; |
| |
| public class DataSources |
| { |
| |
| public static CircuitBreaker newDataSourceCircuitBreaker() |
| { |
| return newDataSourceCircuitBreaker( 5, 1000 * 60 * 5 ); |
| } |
| |
| public static CircuitBreaker newDataSourceCircuitBreaker( int threshold, long timeout ) |
| { |
| @SuppressWarnings( "unchecked" ) |
| Specification<Throwable> in = in( ConnectException.class ); |
| return new CircuitBreaker( threshold, timeout, not( rootCause( in ) ) ); |
| } |
| |
| public static DataSource wrapWithCircuitBreaker( final String dataSourceIdentity, final DataSource pool, final CircuitBreaker circuitBreaker ) |
| { |
| // Create wrapper |
| InvocationHandler handler = new InvocationHandler() |
| { |
| @Override |
| public Object invoke( Object proxy, Method method, Object[] args ) |
| throws Throwable |
| { |
| if ( !circuitBreaker.isOn() ) { |
| Throwable throwable = circuitBreaker.lastThrowable(); |
| if ( throwable != null ) { |
| throw throwable; |
| } else { |
| throw new ServiceImporterException( "Circuit breaker for DataSource " + dataSourceIdentity + " is not on" ); |
| } |
| } |
| |
| try { |
| Object result = method.invoke( pool, args ); |
| circuitBreaker.success(); |
| return result; |
| } catch ( IllegalAccessException e ) { |
| circuitBreaker.throwable( e ); |
| throw e; |
| } catch ( IllegalArgumentException e ) { |
| circuitBreaker.throwable( e ); |
| throw e; |
| } catch ( InvocationTargetException e ) { |
| circuitBreaker.throwable( e.getCause() ); |
| throw e.getCause(); |
| } |
| } |
| |
| }; |
| |
| // Create proxy with circuit breaker |
| return ( DataSource ) Proxy.newProxyInstance( DataSource.class.getClassLoader(), new Class[]{ DataSource.class }, handler ); |
| } |
| |
| private DataSources() |
| { |
| } |
| |
| } |