Java tutorial
/* * Copyright 2004-2012 the Seasar Foundation and the Others. * * 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.seasar.mayaa.impl.source; import java.io.IOException; import java.io.InputStream; import java.net.MalformedURLException; import java.net.URL; import java.util.Date; import javax.servlet.ServletContext; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.seasar.mayaa.FactoryFactory; import org.seasar.mayaa.cycle.scope.ApplicationScope; import org.seasar.mayaa.impl.ParameterAwareImpl; import org.seasar.mayaa.impl.cycle.CycleUtil; import org.seasar.mayaa.impl.util.IOUtil; import org.seasar.mayaa.impl.util.StringUtil; /** * ?Web?????File???Context???SourceDescriptor * * @author Taro KATO (Gluegent Inc.) */ public class ApplicationResourceSourceDescriptor extends ParameterAwareImpl implements ChangeableRootSourceDescriptor { private static final long serialVersionUID = -2775274363708858237L; static final Log LOG = LogFactory.getLog(ApplicationResourceSourceDescriptor.class); private transient ApplicationScope _application; /** File????????? */ private transient URL _url; private transient String _systemID; public ApplicationResourceSourceDescriptor() { // do nothing. } // use while building ServiceProvider. public void setApplicationScope(ApplicationScope application) { if (application == null) { throw new IllegalArgumentException(); } _application = application; } public ApplicationScope getApplicationScope() { if (_application == null) { _application = FactoryFactory.getApplicationScope(); } return _application; } public void setRoot(String root) { // ignore } protected URL getURL() { if (_url == null) { String path = _systemID; if (StringUtil.isEmpty(path)) { path = "/"; } // TODO ???ServletContext??????? ServletContext context = (ServletContext) getApplicationScope().getUnderlyingContext(); try { // TODO GAE for Java???null?????????... _url = context.getResource(path); if (_url == null) { LOG.debug("NG. getResource failed. - " + path); } else { LOG.debug("OK. getResource url succeed. - " + path); } return _url; } catch (MalformedURLException e) { throw new IllegalStateException("invalid: " + path); } } return _url; } /* (non-Javadoc) * @see org.seasar.mayaa.source.SourceDescriptor#exists() */ public boolean exists() { URL url = getURL(); if (url != null) { return true; } // GAE for Java _url?null???Stream??? ServletContext context = (ServletContext) getApplicationScope().getUnderlyingContext(); InputStream resourceAsStream = context.getResourceAsStream(_systemID); try { return resourceAsStream != null; } finally { try { if (resourceAsStream != null) { resourceAsStream.close(); } } catch (IOException e) { return false; } } } /* (non-Javadoc) * @see org.seasar.mayaa.source.SourceDescriptor#getInputStream() */ public InputStream getInputStream() { return IOUtil.openStream(getURL()); } /* (non-Javadoc) * @see org.seasar.mayaa.source.SourceDescriptor#getTimestamp() */ public Date getTimestamp() { return new Date(IOUtil.getLastModified(getURL())); } /* (non-Javadoc) * @see org.seasar.mayaa.impl.ParameterAwareImpl#setSystemID() */ public void setSystemID(String systemID) { if (!StringUtil.equals(_systemID, systemID)) { _systemID = systemID; _url = null; } } /* (non-Javadoc) * @see org.seasar.mayaa.impl.ParameterAwareImpl#getSystemID() */ public String getSystemID() { return _systemID; } // for serialize private void readObject(java.io.ObjectInputStream in) throws java.io.IOException, ClassNotFoundException { in.defaultReadObject(); _application = CycleUtil.getServiceCycle().getApplicationScope(); } }