/*
* $Id: BaseTemplateEngine.java 963612 2010-07-13 07:10:06Z lukaszlenart $
*
* 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
*
* 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.struts2.components.template;
import com.opensymphony.xwork2.util.ClassLoaderUtil;
import com.opensymphony.xwork2.util.logging.Logger;
import com.opensymphony.xwork2.util.logging.LoggerFactory;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;
/**
* Base class for template engines.
*/
public abstract class BaseTemplateEngine implements TemplateEngine {
private static final Logger LOG = LoggerFactory.getLogger(BaseTemplateEngine.class);
/**
* The default theme properties file name. Default is 'theme.properties'
*/
public static final String DEFAULT_THEME_PROPERTIES_FILE_NAME = "theme.properties";
final Map<String, Properties> themeProps = new HashMap<String, Properties>();
public Map getThemeProps(Template template) {
synchronized (themeProps) {
Properties props = themeProps.get(template.getTheme());
if (props == null) {
props = readNewProperties(template);
themeProps.put(template.getTheme(), props);
}
return props;
}
}
private Properties readNewProperties(Template template) {
String propName = buildPropertyFilename(template);
return loadProperties(propName);
}
private Properties loadProperties(String propName) {
InputStream is = readProperty(propName);
Properties props = new Properties();
if (is != null) {
tryToLoadPropertiesFromStream(props, propName, is);
}
return props;
}
private InputStream readProperty(String propName) {
InputStream is = tryReadingPropertyFileFromFileSystem(propName);
if (is == null) {
is = readPropertyFromClasspath(propName);
}
return is;
}
/**
* if its not in filesystem. let's try the classpath
*/
private InputStream readPropertyFromClasspath(String propName) {
return ClassLoaderUtil.getResourceAsStream(propName, getClass());
}
private void tryToLoadPropertiesFromStream(Properties props, String propName, InputStream is) {
try {
props.load(is);
} catch (IOException e) {
LOG.error("Could not load " + propName, e);
} finally {
tryCloseStream(is);
}
}
private void tryCloseStream(InputStream is) {
try {
is.close();
} catch (IOException io) {
LOG.warn("Unable to close input stream", io);
}
}
private String buildPropertyFilename(Template template) {
return new StringBuilder().append(template.getDir())
.append("/")
.append(template.getTheme())
.append("/")
.append(getThemePropertiesFileName()).toString();
}
/**
* WW-1292 let's try getting it from the filesystem
*/
private InputStream tryReadingPropertyFileFromFileSystem(String propName) {
File propFile = new File(propName);
try {
return createFileInputStream(propFile);
} catch (FileNotFoundException e) {
LOG.warn("Unable to find file in filesystem [" + propFile.getAbsolutePath() + "]");
return null;
}
}
private InputStream createFileInputStream(File propFile) throws FileNotFoundException {
InputStream is = null;
if (propFile.exists()) {
is = new FileInputStream(propFile);
}
return is;
}
protected String getFinalTemplateName(Template template) {
String t = template.toString();
if (t.indexOf(".") <= 0) {
return t + "." + getSuffix();
}
return t;
}
protected String getThemePropertiesFileName() {
return DEFAULT_THEME_PROPERTIES_FILE_NAME;
}
protected abstract String getSuffix();
}
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