巴巴运动网权限模块实现参考

1. 定义PermissionTag标签:

/**
 * 权限检查标签类
 */
public class PermissionTag extends TagSupport {
	private static final long serialVersionUID = -5285732412976711256L;

	private String module;
	private String privilege;

	@Override
	public int doStartTag() throws JspException {
		boolean result = false;
		Employee employee = WebUtil.getEmployee((HttpServletRequest) pageContext.getRequest());
		SystemPrivilege privilege = new SystemPrivilege(new SystemPrivilegePK(this.module, this.privilege));
		for (PrivilegeGroup group : employee.getGroups()) {
			if (group.getPrivileges().contains(privilege)) {
				result = true;
				break;
			}
		}
		return result ? EVAL_BODY_INCLUDE : SKIP_BODY;
	}

	public String getModule() {
		return module;
	}

	public void setModule(String module) {
		this.module = module;
	}

	public String getPrivilege() {
		return privilege;
	}

	public void setPrivilege(String privilege) {
		this.privilege = privilege;
	}
}

2. 配置标签tld文件

<?xml version="1.0" encoding="UTF-8" ?>
<taglib xmlns="http://java.sun.com/xml/ns/j2ee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
    version="2.0">
    
  <description>itcast babasport permission taglib</description>
  <display-name>permission taglib</display-name>
  <tlib-version>1.0</tlib-version>
  <short-name>itcast</short-name>
  <uri>http://www.itcast.cn/babasport</uri>

  <tag>
    <description>权限校验标签，有权限就显示标签体的内容，否则不显示</description>
    <name>permission</name>
    <tag-class>com.shop.action.privilege.PermissionTag</tag-class>
    <body-content>JSP</body-content>
    <attribute>
        <description>所在模块</description>
        <name>module</name>
        <required>true</required>
        <rtexprvalue>false</rtexprvalue>
    </attribute>
    <attribute>
        <description>所予权限</description>
        <name>privilege</name>
        <required>true</required>
        <rtexprvalue>false</rtexprvalue>
    </attribute>
  </tag>  
</taglib>

3. 在需要进行权限控制的JSP片段中:

<itcast:permission privilege="update" module="product">
 <div align="center"><a href="/shop/control/product/editUI.do?productid=${entry.id}"><img src="/shop/images/edit.gif" width="15" height="16" border="0"></a></div>
</itcast:permission></td>

// ------ 以上还不够, JSP还不是安全的, 要在JAVA程序中在进行过滤:

4. 定义注解Permission:

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface Permission {
	String module();

	String privilege();
}

5. 在需要进行权限检查的Controller方法上打上注解:

@RequestMapping("/control/product/list")
@Permission(module = "product", privilege = "view")
public String list(ProductBean formbean, HttpServletRequest request) {}

@RequestMapping("/control/product/addUI")
@Permission(module = "product", privilege = "insert")
public String addUI(HttpServletRequest request) throws Exception {}

6. 定义一个Interceptor, 拦截所有需要进行权限检查的URL:
SpringMVC中的实现:

public class PrivilegeRequestInterceptor extends HandlerInterceptorAdapter {

	@Override
	public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
		// like /shop/control/department/list.do
		String requestURI = WebUtil.getRequestURI(request);
		// like /control/department/list
		String reqMapping = requestURI.substring(5, requestURI.indexOf(".do"));
		Map<String, String[]> reqInfo = new LinkedHashMap<String, String[]>();
		Method targetMethod = getTargetMethod(handler, reqMapping);
		if (reqMapping.startsWith("/control/")) {//只对办公平台中的action进行校验
			boolean validateResult = validate(request, targetMethod);
			reqInfo.put("permission validate:", new String[] { validateResult + "" });
			log.debug("request info: " + getJSONString(reqInfo));
			if (!validateResult) {//没有权限的时候执行下面这段代码
				request.setAttribute("message", "您没有执行该操作的权限");
				request.setAttribute("urladdress", SiteUrl.readUrl("control.control.right"));
				request.getRequestDispatcher("/WEB-INF/page/share/message.jsp").forward(request, response);
				return false;
			}
			return true;
		}
		log.debug("request info: " + getJSONString(reqInfo));
		return true;
	}

	private Method getTargetMethod(Object handler, String reqMapping) {
		Method[] methods = handler.getClass().getDeclaredMethods();
		for (Method method : methods) {
			boolean isAnnoted = method.isAnnotationPresent(RequestMapping.class);
			RequestMapping mappingAnnoted = method.getAnnotation(RequestMapping.class);
			if (isAnnoted && reqMapping.equals(mappingAnnoted.value()[0])) {
				return method;
			}
		}
		return null;
	}

	/**
	 * 权限校验
	 * @return
	 */
	private boolean validate(HttpServletRequest request, Method targetMethod) {
		if (targetMethod == null || !targetMethod.isAnnotationPresent(Permission.class)) {
			return true;
		}
		Permission permission = targetMethod.getAnnotation(Permission.class);//得到方法上的注解
		//下面是得到执行方法需要的权限
		SystemPrivilegePK targetPrivilege = new SystemPrivilegePK(permission.module(), permission.privilege());
		Employee employee = WebUtil.getEmployee(request);
		for (PrivilegeGroup group : employee.getGroups()) {
			for (SystemPrivilege privilege : group.getPrivileges()) {
				if (privilege.getPermission().equals(targetPrivilege)) {
					return true;
				}
			}
		}
		return false;
	}

	@Override
	public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
			ModelAndView modelAndView) throws Exception {
		Collection<String> headNames = response.getHeaderNames();
		for (String headName : headNames) {
			log.debug("HTTP head{" + headName + ":" + response.getHeader(headName) + "}");
		}
		super.postHandle(request, response, handler, modelAndView);
	}

	@Override
	public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
			throws Exception {
		super.afterCompletion(request, response, handler, ex); // 可以在此通过判断ex是否为null,来检查Controller是否抛出了异常.
	}
}

7. 在springmvc-servlet.xml中配置Interceptor:

<bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping">
<property name="interceptors">
	<list>
		<bean class="com.shop.web.support.PrivilegeRequestInterceptor" />
	</list>
</property>
</bean>