springboot 自定义权限标签(tld),在freemarker引用

第一步:引入jar包

        <dependency>            <groupId>javax.servlet.jsp</groupId>            <artifactId>jsp-api</artifactId>            <version>2.2.1-b03</version>        </dependency>  

第二步:自定义标签类

import java.util.Map;import java.util.Set;import javax.servlet.http.HttpServletRequest;import org.jasig.cas.client.authentication.AttributePrincipal;import org.springframework.web.servlet.tags.RequestContextAwareTag;import com.goodidea.sso.dto.PrivilegesDto;import com.goodidea.sso.dto.ResourcesDto;import com.goodidea.sso.service.PrivilegesService;/** * * @ClassName: PrivilegeTag * @Description: 权限标签类 * @author lsg* @date 2017年9月12日 下午5:36:01 * */public class PrivilegeTag extends RequestContextAwareTag{    private static final long serialVersionUID = 534416848523276042L;    private String menuAlias;    private String priAlias;    public String getMenuAlias() {        return menuAlias;    }    public void setMenuAlias(String menuAlias) {        this.menuAlias = menuAlias;    }    public String getPriAlias() {        return priAlias;    }    public void setPriAlias(String priAlias) {        this.priAlias = priAlias;    }    @Override    protected int doStartTagInternal()  {        // TODO Auto-generated method stub        boolean result = false;         try {            HttpServletRequest request = (HttpServletRequest) pageContext.getRequest();             AttributePrincipal principal = (AttributePrincipal)request.getUserPrincipal();             Map<String, Object> attributes = principal.getAttributes();            String username=(String) attributes.get("username");            PrivilegesService  privilegesService= (PrivilegesService)this.getRequestContext().getWebApplicationContext().getBean("privilegesServiceImpl");            Set<ResourcesDto> dto = privilegesService.findResourcesByUsername(username);            for (ResourcesDto resourcesDto : dto) {                if(this.menuAlias.equals(resourcesDto.getAlias())){                    for (PrivilegesDto pdto : resourcesDto.getPrivileges()) {                        if(this.priAlias.equals(pdto.getAlias())){                             result = true;                        }                    }                }            }         } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();            result =false;        }        return result? EVAL_BODY_INCLUDE : SKIP_BODY;    }}

第三步:创建tld标签,放入在web-inf下

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE taglib PUBLIC "-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.1//EN" "http://java.sun.com/j2ee/dtds/web-jsptaglibrary_1_1.dtd"><taglib>    <tlibversion>1.0</tlibversion>    <jspversion>1.1</jspversion>    <shortname>privilege</shortname>    <tag>        <name>privilege</name>        <tagclass>com.goodidea.sso.core.PrivilegeTag</tagclass>        <bodycontent>empty</bodycontent> <!--这里如果设为empty,则无body-->        <attribute>            <name>menuAlias</name>            <required>true</required>            <rtexprvalue>true</rtexprvalue>        </attribute>        <attribute>            <name>priAlias</name>            <required>true</required>            <rtexprvalue>true</rtexprvalue>        </attribute>    </tag></taglib>

第四:页面引用

<#assign p=JspTaglibs["/WEB-INF/tld/privilege.tld"] /> 

注意tld,如果不在web.xml上进行引入的话,就放在web-inf下,要不然会报找不到tld资源异常