package org.douyu.plugins.freemarker;
import java.io.File;
import java.io.Writer;
import java.util.Map;
import java.util.HashMap;
import douyu.mvc.Context;
import douyu.mvc.ViewException;
import douyu.mvc.ViewManager;
import freemarker.template.Configuration;
import freemarker.template.DefaultObjectWrapper;
import freemarker.template.Template;
/**
*
* @author ZHH
*
*/
public class FreeMarkerViewManager implements ViewManager {
private static final String defaultContentType = "text/html; charset=UTF-8";
private static final String defaultEncoding = "UTF-8";
private Context douyuContext;
private Configuration config = new Configuration();
private Map<String, Object> root = new HashMap<String, Object>();
FreeMarkerViewManager(Context douyuContext) {
this.douyuContext = douyuContext;
if (douyuContext.getHttpServletResponse().getContentType() == null)
douyuContext.getHttpServletResponse().setContentType(defaultContentType);
try {
config.setDirectoryForTemplateLoading(new File(douyuContext.getApplicationBase()));
config.setObjectWrapper(new DefaultObjectWrapper());
} catch (Throwable t) {
throw new ViewException(t);
}
}
private String defaultViewFileName() {
StringBuilder viewFileName = new StringBuilder(50);
viewFileName.append(douyuContext.getControllerClassName().replace('.', File.separatorChar));
viewFileName.append(".");
viewFileName.append(douyuContext.getActionName());
viewFileName.append(".ftl");
return viewFileName.toString();
}
@Override
public void out() {
out(defaultViewFileName());
}
@Override
public void out(String viewFileName) {
try {
Template template = config.getTemplate(viewFileName, defaultEncoding);
if (template != null) {
Writer writer = douyuContext.getHttpServletResponse().getWriter();
//TODO
//template.process内部会自动调用writer.flush，
//如果在输出ftl文件后又接着输出jsp，那么jsp会出异常:
//java.lang.IllegalStateException: Cannot create a session after the response has been committed
//因为调用writer.flush会导致响应头会被提交
template.process(root, writer);
//writer.flush();
//writer.close();
}
} catch (Throwable t) {
throw new ViewException(t);
}
}
@Override
public void put(String key, Object value) {
root.put(key, value);
}
}