| /* |
| * Copyright 1999-2004 The Apache Software Foundation. |
| * |
| * 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.apache.cocoon.components.modules.output; |
| |
| import java.util.Iterator; |
| import java.util.Map; |
| |
| import org.apache.avalon.framework.configuration.Configuration; |
| import org.apache.avalon.framework.logger.Logger; |
| import org.apache.cocoon.environment.ObjectModelHelper; |
| import org.apache.cocoon.environment.Session; |
| |
| /** |
| * Abstraction layer to encapsulate different output |
| * destinations. Configuration option <key-prefix> defaults to |
| * "org.apache.cocoon.components.modules.output.OutputModule"+":" |
| * |
| * Can be used with different isolation-level: default is "0" being |
| * no isolation at all, values are immediately visible but are removed |
| * on a rollback; "1" keeps the values at a save place until either |
| * rollback or commit is called. Then values are either discarded or |
| * copied to the final destination. |
| * |
| * @author <a href="mailto:haul@apache.org">Christian Haul</a> |
| * @version CVS $Id: SessionAttributeOutputModule.java,v 1.3 2004/03/05 13:02:49 bdelacretaz Exp $ |
| */ |
| public class SessionAttributeOutputModule extends AbstractOutputModule implements OutputModule { |
| |
| public final String PREFIX = "org.apache.cocoon.components.modules.output.OutputModule"; |
| public final String TRANS_PREFIX = "org.apache.cocoon.components.modules.output.OutputModule.SessionAttributeOutputModule.transient"; |
| public final String ROLLBACK_LIST = "org.apache.cocoon.components.modules.output.OutputModule.SessionAttributeOutputModule.rollback"; |
| |
| /** |
| * communicate an attribute value to further processing logic. |
| * @param modeConf column's mode configuration from resource |
| * description. This argument is optional. |
| * @param objectModel The objectModel |
| * @param name The attribute's label, consisting of "table.column" |
| * or "table.column[index]" in case of multiple attributes of the |
| * same spec. |
| * @param value The attriute's value. |
| * */ |
| public void setAttribute( Configuration modeConf, Map objectModel, String name, Object value ) { |
| if (this.settings.get("isolation-level","0").equals("1")) { |
| if (getLogger().isDebugEnabled()) |
| getLogger().debug("setting transient ['"+name+"'] to ['"+value+"']"); |
| this.transientSetAttribute(objectModel, TRANS_PREFIX, name, value); |
| } else { |
| // use read uncommitted isolation level |
| |
| Session session = ObjectModelHelper.getRequest(objectModel).getSession(); |
| |
| name = getName(name); |
| |
| if (!this.attributeExists(objectModel, ROLLBACK_LIST, name)) { |
| Object tmp = session.getAttribute(name); |
| this.transientSetAttribute(objectModel, ROLLBACK_LIST, name, tmp); |
| } |
| |
| if (getLogger().isDebugEnabled()) |
| getLogger().debug("setting ['"+name+"'] to ['"+value+"']"); |
| session.setAttribute(name, value); |
| } |
| |
| } |
| |
| |
| |
| /** |
| * If a database transaction needs to rollback, this is called to |
| * inform the further processing logic about this fact. All |
| * already set attribute values are invalidated. <em>This is difficult |
| * because only the request object can be used to synchronize this |
| * and build some kind of transaction object. Beaware that sending |
| * your data straight to some beans or other entities could result |
| * in data corruption!</em> |
| * */ |
| public void rollback( Configuration modeConf, Map objectModel, Exception e ) { |
| if (this.settings.get("isolation-level","0").equals("1")) { |
| if (getLogger().isDebugEnabled()) |
| getLogger().debug("rolling back"); |
| this.rollback(objectModel, TRANS_PREFIX); |
| } else { |
| |
| if (getLogger().isDebugEnabled()) |
| getLogger().debug("start rolling back"); |
| |
| Session session = ObjectModelHelper.getRequest(objectModel).getSession(); |
| Object tmp = this.prepareCommit(objectModel,ROLLBACK_LIST); |
| if (tmp != null) { |
| Map rollbackList = (Map) tmp; |
| Iterator iter = rollbackList.keySet().iterator(); |
| while(iter.hasNext()) { |
| String key = (String) iter.next(); |
| Object val = rollbackList.get(key); |
| if (val != null) { |
| if (getLogger().isDebugEnabled()) |
| getLogger().debug("rolling back ['"+key+"'] to ['"+val+"']"); |
| session.setAttribute(key, val); |
| } else { |
| if (getLogger().isDebugEnabled()) |
| getLogger().debug("rolling back ['"+key+"']"); |
| session.removeAttribute(key); |
| } |
| } |
| } |
| } |
| |
| if (getLogger().isDebugEnabled()) |
| getLogger().debug("done rolling back"); |
| |
| String prefix = (String) this.settings.get("key-prefix", PREFIX ); |
| if (prefix!="") { |
| ObjectModelHelper.getRequest(objectModel).getSession().setAttribute(prefix+":",e.getMessage()); |
| } else { |
| ObjectModelHelper.getRequest(objectModel).getSession().setAttribute("errorMessage",e.getMessage()); |
| } |
| } |
| |
| |
| /** |
| * Signal that the database transaction completed |
| * successfully. See notes on @link{rollback}. |
| * */ |
| public void commit( Configuration modeConf, Map objectModel ) { |
| if (this.settings.get("isolation-level","0").equals("1")) { |
| |
| Logger logger = getLogger(); |
| if (logger.isDebugEnabled()) |
| logger.debug("prepare commit"); |
| |
| Map aMap = this.prepareCommit(objectModel, TRANS_PREFIX); |
| if (aMap == null) { |
| return; |
| } |
| |
| Iterator iter = aMap.keySet().iterator(); |
| if (!iter.hasNext()){ |
| return; |
| } |
| |
| String prefix = (String) this.settings.get("key-prefix", PREFIX ); |
| if (prefix != "") { |
| prefix = prefix+":"; |
| } else { |
| prefix = null; |
| } |
| Session session = ObjectModelHelper.getRequest(objectModel).getSession(); |
| while (iter.hasNext()) { |
| String key = (String) iter.next(); |
| Object value = aMap.get(key); |
| if (prefix != null) { key = prefix + key; } |
| if (logger.isDebugEnabled()) |
| logger.debug("committing ['"+key+"'] to ['"+value+"']"); |
| session.setAttribute(key, value); |
| } |
| |
| if (logger.isDebugEnabled()) |
| logger.debug("done commit"); |
| |
| } else { |
| if (getLogger().isDebugEnabled()) |
| getLogger().debug("commit"); |
| this.prepareCommit(objectModel, ROLLBACK_LIST); |
| } |
| |
| } |
| |
| protected String getName( String name ) { |
| String prefix = (String) this.settings.get("key-prefix", PREFIX ); |
| return (prefix == "" ? name : prefix+":"+name); |
| } |
| |
| } |