PermissionTag.java

package edu.gatech.oad.rocket.findmythings.server.util.tags;

import freemarker.core.Environment;
import freemarker.template.TemplateDirectiveBody;
import freemarker.template.TemplateException;
import freemarker.template.TemplateModelException;

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

/**
 * <p>Equivalent to {@link org.apache.shiro.web.tags.PermissionTag}</p>
 */
@SuppressWarnings("rawtypes")
abstract class PermissionTag extends SecureTag {
	String getName(Map params) {
		return getParam(params, "name");
	}

	@Override
	protected void verifyParameters(Map params) throws TemplateModelException {
		String permission = getName(params);

		if (permission == null || permission.length() == 0) {
			throw new TemplateModelException("The 'name' tag attribute must be set.");
		}
	}

	@Override
	public void render(Environment env, Map params, TemplateDirectiveBody body) throws IOException, TemplateException {
		String p = getName(params);

		boolean show = showTagBody(p);
		if (show) {
			renderBody(env, body);
		}
	}

	boolean isPermitted(String p) {
		return getSubject() != null && getSubject().isPermitted(p);
	}

	protected abstract boolean showTagBody(String p);
}