看了网上一些关于权限控制的帖子,越看越迷糊,什么用AOP(Aspect Oriented Programming,面向方面编程),用容器,RBAC(基于角色的访问控制方法),SSO,Jive的Proxy模式等等等等,且又是role又是group,真是头都大了,先写个简单的实现方法,以后再研究高深的。 此方法不依赖容器 框架,适用于小系统(主要JSP页面要少于100,因为是硬编码到JSP),适用于要精确控制页面field的情况较多的系统。 (插句话:要分清权限控制与业务逻辑,业务逻辑就是情况由系统运行时的某些条件决定,如学生管理系统中,某一学生进入系统,只能看自己的记录,因为可看的记录是由学号来决定的,所以这是业务逻辑,而又如学生不能看老师的记录,这是有学生的身份来决定的,所以这是权限控制。) 好了,进入正题! 建表:
| user(user信息: userID userPassword 等) role(role描述:roleID roleDesc) permission(permission描述:permissionID permissionDesc) user-role(user role对应关系表:userID roleID) role-permission(role permission对应关系表:roleID permissionID) user-permission(user permission对应关系表:userID permissionID) |
重要申明: 1 此处role没有继承关系,只是permission的集合 2 user-permission表只是为了方便,其数据是根据user-role role-permission两表得来,只有在user-role role-permission两表有更新的时候更新此表,并不能单独赋予user某个permission,只能赋予user一个或多个role。 3 permission的分配,这是一个难点,很多比较复杂的权限控制系统也是因为这个才发展出来,此处把它尽量想简单,不考虑业务逻辑,以页面为视角,分两层,首先是需要控制的jsp页面,然后是需要控制的页面field(包括link,text,textbox,button等等),field这一层还有privilege之分(R和W,即可读和可写) 基本思路:进入JSP页面时,检查用户信息,查到用户有此permission就包含此代码,如果没有此permission就不包含此代码,此功能由Tag来完成(不会写Tag?不要紧,抄!)。看代码吧! 1 建表(如上) 2 建两个class(bean) (UserProfile是用户基本信息 UserPermission是permission )
| UserProfile.java: package com.××.××.××; import java.util.Collection; public class UserProfile { private String userId; private String userType; private String companyNo; private String companyName; private String companyType; private Collection userPermissions; |
| public String getUserId() { return userId; } public void setUserId(String userId) { this.userId = userId; } public String getUserType() { return userType; } public void setUserType(String userType) { this.userType = userType; } public String getCompanyNo() { return companyNo; } public void setCompanyNo(String companyNo) { this.companyNo = companyNo; } public String getCompanyName() { return companyName; } public void setCompanyName(String companyName) { this.companyName = companyName; } public String getCompanyType() { return companyType; } public void setCompanyType(String companyType) { this.companyType = companyType; } public Collection getUserPermissions() { return userPermissions; } public void setUserPermissions(Collection userPermissions) { this.userPermissions = userPermissions; } } UserPermission.java: package com.××.××.××; public class UserPermission { private int permissionId; private String privilege; public int getPermissionId() { return permissionId; } public void setPermissionId(int permissionId) { this.permissionId = permissionId; |
| } public String getPrivilege() { return privilege; } public void setPrivilege(String privilege) { this.privilege = privilege; } } 3 加两个Tag(Page与Field): SecurityTagForPage.java: package com.**.**.taglib; import java.util.*; public class SecurityTagForPage extends TagSupport { private int permissionID; public int doEndTag() throws JspException { HttpSession session = pageContext.getSession(); //登陆时把该user的userProfile放到session里 UserProfile userProfile = (UserProfile)session.getAttribute("userProfile"); Collection collection= userProfile.getUserPermissions(); Iterator it = collection.iterator() ; while(it.hasNext()) { UserPermission userPermission = (UserPermission)it.next(); if ((permissionID == userPermission.getPermissionId())) { return EVAL_PAGE; } } return SKIP_PAGE; } public int getPermissionID() { return permissionID; } public void setPermissionID(int permissionID) { this.permissionID = permissionID; } } |
| SecurityTagForField: public class SecurityTagForField extends TagSupport { private int permissionID; private String privilege; public int doStartTag() throws JspException { HttpSession session = pageContext.getSession(); UserProfile userProfile = (UserProfile)session.getAttribute("userProfile"); Collection collection= userProfile.getUserPermissions(); Iterator it = collection.iterator() ; while(it.hasNext()) { UserPermission userPermission = (UserPermission)it.next(); if (privilege ==null) { if ( (permissionID == userPermission.getPermissionId())) { return EVAL_BODY_INCLUDE; } } else { if ((permissionID == userPermission.getPermissionId()) &&(privilege.equals(userPermission.getPrivilege()))) { return EVAL_BODY_INCLUDE; } } } return SKIP_BODY; } public int getPermissionID() { return permissionID; } public void setPermissionID(int permissionID) { this.permissionID = permissionID; } public String getPrivilege() { return privilege; |
| } public void setPrivilege(String privilege) { this.privilege = privilege; } } |
4 在web-inf目录下建个securityTag.tld文件,内容如下:(改一下class的目录)
| <?xml version="1.0" encoding="ISO-8859-1"?> <!DOCTYPE taglib PUBLIC "-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.1//EN" "http://java.sun.com/j2ee/dtds/web-jsptaglibrary_1_1.dtd"> <!-- a tag library descriptor --> <taglib> <tlibversion>1.0</tlibversion> <jspversion>1.1</jspversion> <shortname>security</shortname> <uri/> <info> access control! </info> <tag> <name>securityForField</name> <tagclass>com.companyname.prjname.taglib.SecurityTagForField</tagclass> <attribute> <name>permissionID</name> <required>true</required> </attribute> <attribute> <name>privilege</name> </attribute> </tag> <tag> |
| <name>securityForPage</name> <tagclass>com.companyname.prjname.taglib.SecurityTagForPage</tagclass> <attribute> <name>permissionID</name> <required>true</required> </attribute> </tag> </taglib> |
5 修改需要控制的jsp 在jsp页面这样写:
| <%@ taglib uri="/WEB-INF/securityTag.tld" prefix="security" %> <%@ page import="com.hp.elog2.util.Util" %> <security:securityForPage permissionID="36" /> ....... <security:securityForField permissionID="46" privilege="R"> <td><html:text name="formBean" property="property1" readonly="true" /></td> </security:securityForField> <security:securityForField permissionID="46" privilege="W"> <td><html:text name="formBean" property="property1" /></td> </security:securityForField> ...... |
这样就大功告成了,建议在所有jsp页面完成后再做权限控制这一块(添加Tag),主要都是些Copy+C和Copy+V的工作。 此方法最大的问题就是hardcode太多,但结构简单,思路清晰,适用范围广。 复杂的方法希望同道之士于我联系leon_sandy@tom.com,共同研究!
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