TemplateHandler.java

package me.xhh.mail;

import java.io.IOException;
import java.io.StringWriter;
import java.util.Locale;
import java.util.Map;

import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.TemplateException;

public class TemplateHandler {

	/**
	 * For each template, there must be a file named<br/>
	 * <code>template.toString() + ".ftl"</code><br/>
	 * in the template folder.
	 * 
	 * @see TemplateHandler#processTemplate(MailTemplate, Map)
	 */
	public enum MailTemplate {
		User_UserRegistration, Admin_UserRegistration,
	}

	/** Where the mail templates are placed. */
	private static final String PATH_PREFIX = "/me/xhh/mail/";
	private static final String TEMPLATE_FILE_SUFFIX = ".ftl";

	private static Configuration fmConfig;

	static {
		fmConfig = new Configuration();
		fmConfig.setClassForTemplateLoading(TemplateHandler.class, PATH_PREFIX);
		fmConfig.setEncoding(Locale.getDefault(), "UTF-8");
	}

	/**
	 * Process the email template. The template file to be used is:<br/>
	 * "{@link #PATH_PREFIX}/str/{@link #TEMPLATE_FILE_SUFFIX}"<br/>
	 * (where str is templateType.toString())
	 * 
	 * @param mailTemplate
	 *            the mail template to be used
	 * @param valuesMap
	 *            the values to be used to replace the placeholder in the template file
	 * @return the result of the template content parsed with the values
	 * @throws IOException
	 * @throws TemplateException
	 */
	public static String processTemplate(MailTemplate mailTemplate, Map<String, Object> valuesMap) throws IOException,
			TemplateException {
		Template template = fmConfig.getTemplate(mailTemplate.toString() + TEMPLATE_FILE_SUFFIX);
		StringWriter strWriter = new StringWriter();
		template.process(valuesMap, strWriter);
		String resultStr = strWriter.toString();
		return resultStr;
	}

}