FreeMarker解析字串模板

重寫Freemarker的模板載入器即可:
import java.io.IOException;
import java.io.Reader;
import java.io.StringReader;
import java.util.HashMap;
import java.util.Map;
import freemarker.cache.TemplateLoader;

public class StringTemplateLoader implements TemplateLoader {

private static final String DEFAULT_TEMPLATE_KEY = "_default_template_key";
private Map templates = new HashMap();
public StringTemplateLoader(String defaultTemplate) {
if (defaultTemplate != null && !defaultTemplate.equals("")) {
templates.put(DEFAULT_TEMPLATE_KEY, defaultTemplate);
}
}

public void AddTemplate(String name, String template) {
if (name == null || template == null || name.equals("")|| template.equals("")) {
return;
}

if (!templates.containsKey(name)) {
templates.put(name, template);
}
}

public void closeTemplateSource(Object templateSource)
throws IOException {

}

public Object findTemplateSource(String name) throws IOException {
if (name == null || name.equals("")) {
name = DEFAULT_TEMPLATE_KEY;
}
return templates.get(name);
}

public long getLastModified(Object templateSource) {
return 0;
}

public Reader getReader(Object templateSource, String encoding) throws IOException {
return new StringReader((String) templateSource);

}
}
測試類別：
import java.io.StringWriter;
import java.util.HashMap;
import java.util.Map;

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

public class Test {

/**
 * @param args
 */
public static void main(String[] args) throws Exception {
Configuration cfg = new Configuration();    
        cfg.setTemplateLoader(new StringTemplateLoader("hello：${user}"));    
        cfg.setDefaultEncoding("UTF-8");    

        Template template = cfg.getTemplate("");    

        Map root = new HashMap();    
        root.put("user", "lunzi");    

        StringWriter writer = new StringWriter();    
        template.process(root, writer);    
        System.out.println(writer.toString());          
}

}