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.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; /** * ApplicationScope???SourceDescriptor * * @author Masataka Kurihara (Gluegent, Inc.) * @author Koji Suga (Gluegent Inc.) */ public class ApplicationSourceDescriptor extends ParameterAwareImpl implements ChangeableRootSourceDescriptor { private static final long serialVersionUID = -2775274363708858237L; private static final Log LOG = LogFactory.getLog(ApplicationSourceDescriptor.class); public static final String WEB_INF = "/WEB-INF"; private transient ApplicationScope _application; /** File????????? */ private transient Boolean _useFile; private transient URL _url; private FileSourceDescriptor _fileSourceDescriptor; public ApplicationSourceDescriptor() { _fileSourceDescriptor = new FileSourceDescriptor(); _fileSourceDescriptor.setRoot(""); } // 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) { _fileSourceDescriptor.setRoot(root); } protected URL getURL() { String path = _fileSourceDescriptor.getRealPath(); if (StringUtil.isEmpty(path)) { path = "/"; } // TODO ???ServletContext??????? ServletContext context = (ServletContext) getApplicationScope().getUnderlyingContext(); try { URL url = context.getResource(path); return url; } catch (MalformedURLException e) { throw new IllegalStateException("invalid: " + path); } } /** * ???????ServletContext?URL?? * ServletContext????????????? * ??????????????????? * * @return ?????true */ protected final boolean canUseFile() { if (_useFile == null) { _useFile = Boolean.TRUE; if (_fileSourceDescriptor.exists() == false) { _useFile = Boolean.FALSE; URL url = getURL(); if (url != null) { _url = url; if (LOG.isDebugEnabled()) { LOG.debug(getSystemID() + " is read by URL (" + _url + ")"); } } } else { if (LOG.isDebugEnabled()) { LOG.debug(getSystemID() + " is read by FILE (" + _fileSourceDescriptor.getFile() + ")"); } } } return _useFile.booleanValue(); } /* (non-Javadoc) * @see org.seasar.mayaa.source.SourceDescriptor#exists() */ public boolean exists() { if (canUseFile()) { return _fileSourceDescriptor.exists(); } return _url != null; } /* (non-Javadoc) * @see org.seasar.mayaa.source.SourceDescriptor#getInputStream() */ public InputStream getInputStream() { if (canUseFile()) { return _fileSourceDescriptor.getInputStream(); } return IOUtil.openStream(_url); } /* (non-Javadoc) * @see org.seasar.mayaa.source.SourceDescriptor#getTimestamp() */ public Date getTimestamp() { if (canUseFile()) { return _fileSourceDescriptor.getTimestamp(); } return new Date(IOUtil.getLastModified(_url)); } /* (non-Javadoc) * @see org.seasar.mayaa.impl.ParameterAwareImpl#setSystemID() */ public void setSystemID(String systemID) { _fileSourceDescriptor.setSystemID(systemID); } /* (non-Javadoc) * @see org.seasar.mayaa.impl.ParameterAwareImpl#getSystemID() */ public String getSystemID() { return _fileSourceDescriptor.getSystemID(); } // for serialize private void readObject(java.io.ObjectInputStream in) throws java.io.IOException, ClassNotFoundException { in.defaultReadObject(); _application = CycleUtil.getServiceCycle().getApplicationScope(); } }