Spring Security 3.x 完整入门教程_springsharp-优快云博客

本Blog所有内容不得随意转载，版权属于作者所有。如需转载请与作者联系（ fastzch@163.com QQ：9184314）。
未经许可的转载，本人保留一切法律权益。

Spring Security 3.x 出来一段时间了，跟Acegi是大不同了，与2.x的版本也有一些小小的区别，网上有一些文档，也有人翻译Spring Security 3.x的guide，但通过阅读guide，无法马上就能很容易的实现一个完整的实例。

我花了点儿时间，根据以前的实战经验，整理了一份完整的入门教程，供需要的朋友们参考。
1，建一个web project，并导入所有需要的lib，这步就不多讲了。
2，配置web.xml，使用Spring的机制装载：

<? xml version="1.0" encoding="UTF-8" ?>

< web-app version ="2.4" 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-app_2_4.xsd" >

< context-param >

< param-name > contextConfigLocation </ param-name >

< param-value > classpath:applicationContext*.xml </ param-value >

</ context-param >

< listener >

< listener-class >

org.springframework.web.context.ContextLoaderListener

</ listener-class >

</ listener >

< filter >

< filter-name > springSecurityFilterChain </ filter-name >

< filter-class >

org.springframework.web.filter.DelegatingFilterProxy

</ filter-class >

</ filter >

< filter-mapping >

< filter-name > springSecurityFilterChain </ filter-name >

< url-pattern > /* </ url-pattern >

</ filter-mapping >

< welcome-file-list >

< welcome-file > login.jsp </ welcome-file >

</ welcome-file-list >

</ web-app >

这个文件中的内容我相信大家都很熟悉了，不再多说了。

2，来看看applicationContext-security.xml这个配置文件，关于Spring Security的配置均在其中：

<? xml version="1.0" encoding="UTF-8" ?>

< beans:beans xmlns ="http://www.springframework.org/schema/security"

xmlns:beans ="http://www.springframework.org/schema/beans"

xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation ="http://www.springframework.org/schema/beans

http://www.springframework.org/schema/beans/spring-beans-3.0.xsd

http://www.springframework.org/schema/security

http://www.springframework.org/schema/security/spring-security-3.0.xsd" >

< http access-denied-page ="/403.jsp" >

< intercept-url pattern ="/login.jsp" filters ="none" />

< form-login login-page ="/login.jsp"

authentication-failure-url ="/login.jsp?error=true"

default-target-url ="/index.jsp" />

< logout logout-success-url ="/login.jsp" />

< http-basic />

< custom-filter before ="FILTER_SECURITY_INTERCEPTOR"

ref ="myFilter" />

</ http >

<!-- 一个自定义的filter，必须包含authenticationManager,accessDecisionManager,securityMetadataSource三个属性，

我们的所有控制将在这三个类中实现，解释详见具体配置 -->

< beans:bean id ="myFilter" class ="com.robin.erp.fwk.security.MyFilterSecurityInterceptor" >

< beans:property name ="authenticationManager"

ref ="authenticationManager" />

< beans:property name ="accessDecisionManager"

ref ="myAccessDecisionManagerBean" />

< beans:property name ="securityMetadataSource"

ref ="securityMetadataSource" />

</ beans:bean >

< authentication-manager alias ="authenticationManager" >

< authentication-provider

user-service-ref ="myUserDetailService" >

<!-- 如果用户的密码采用加密的话，可以加点“盐”

<password-encoder hash="md5" />

-->

</ authentication-provider >

</ authentication-manager >

< beans:bean id ="myUserDetailService"

class ="com.robin.erp.fwk.security.MyUserDetailService" />

< beans:bean id ="myAccessDecisionManagerBean"

class ="com.robin.erp.fwk.security.MyAccessDecisionManager" >

</ beans:bean >

< beans:bean id ="securityMetadataSource"

class ="com.robin.erp.fwk.security.MyInvocationSecurityMetadataSource" />

</ beans:beans >

3，来看看自定义filter的实现：

package com.robin.erp.fwk.security;

import java.io.IOException;

import javax.servlet.Filter;

import javax.servlet.FilterChain;

import javax.servlet.FilterConfig;

import javax.servlet.ServletException;

import javax.servlet.ServletRequest;

import javax.servlet.ServletResponse;

import org.springframework.security.access.SecurityMetadataSource;

import org.springframework.security.access.intercept.AbstractSecurityInterceptor;

import org.springframework.security.access.intercept.InterceptorStatusToken;

import org.springframework.security.web.FilterInvocation;

import org.springframework.security.web.access.intercept.FilterInvocationSecurityMetadataSource;

public class MyFilterSecurityInterceptor extends AbstractSecurityInterceptor

implements Filter {

private FilterInvocationSecurityMetadataSource securityMetadataSource;

// ~ Methods

// ========================================================================================================

/**

* Method that is actually called by the filter chain. Simply delegates to

* the {@link #invoke(FilterInvocation)} method.

* @param request

* the servlet request

* @param response

* the servlet response

* @param chain

* the filter chain

* @throws IOException

* if the filter chain fails

* @throws ServletException

* if the filter chain fails

public void doFilter(ServletRequest request, ServletResponse response,

FilterChain chain) throws IOException, ServletException {

FilterInvocation fi = new FilterInvocation(request, response, chain);

invoke(fi);

}

public FilterInvocationSecurityMetadataSource getSecurityMetadataSource() {

return this.securityMetadataSource;

}

public Class<? extends Object> getSecureObjectClass() {

return FilterInvocation.class;

}

public void invoke(FilterInvocation fi) throws IOException,

ServletException {

InterceptorStatusToken token = super.beforeInvocation(fi);

try {

fi.getChain().doFilter(fi.getRequest(), fi.getResponse());

} finally {

super.afterInvocation(token, null);

}

public SecurityMetadataSource obtainSecurityMetadataSource() {

return this.securityMetadataSource;

}

public void setSecurityMetadataSource(

FilterInvocationSecurityMetadataSource newSource) {

this.securityMetadataSource = newSource;

}

@Override

public void destroy() {

}

@Override

public void init(FilterConfig arg0) throws ServletException {

}

最核心的代码就是invoke方法中的InterceptorStatusToken token = super.beforeInvocation(fi);这一句，即在执行doFilter之前，进行权限的检查，而具体的实现已经交给accessDecisionManager了，下文中会讲述。

4，来看看authentication-provider的实现：

package com.robin.erp.fwk.security;

import java.util.ArrayList;

import java.util.Collection;

import org.springframework.dao.DataAccessException;

import org.springframework.security.core.GrantedAuthority;

import org.springframework.security.core.authority.GrantedAuthorityImpl;

import org.springframework.security.core.userdetails.User;

import org.springframework.security.core.userdetails.UserDetails;

import org.springframework.security.core.userdetails.UserDetailsService;

import org.springframework.security.core.userdetails.UsernameNotFoundException;

public class MyUserDetailService implements UserDetailsService {

@Override

public UserDetails loadUserByUsername(String username)

throws UsernameNotFoundException, DataAccessException {

Collection<GrantedAuthority> auths=new ArrayList<GrantedAuthority>();

GrantedAuthorityImpl auth2=new GrantedAuthorityImpl("ROLE_ADMIN");

auths.add(auth2);

if(username.equals("robin1")){

auths=new ArrayList<GrantedAuthority>();

GrantedAuthorityImpl auth1=new GrantedAuthorityImpl("ROLE_ROBIN");

auths.add(auth1);

}

// User(String username, String password, boolean enabled, boolean accountNonExpired,

// boolean credentialsNonExpired, boolean accountNonLocked, Collection<GrantedAuthority> authorities) {

User user = new User(username,

"robin", true, true, true, true, auths);

return user;

}

在这个类中，你就可以从数据库中读入用户的密码，角色信息，是否锁定，账号是否过期等，我想这么简单的代码就不再多解释了。

5，对于资源的访问权限的定义，我们通过实现FilterInvocationSecurityMetadataSource这个接口来初始化数据。

package com.robin.erp.fwk.security;

import java.util.ArrayList;

import java.util.Collection;

import java.util.HashMap;

import java.util.Iterator;

import java.util.Map;

import org.springframework.security.access.ConfigAttribute;

import org.springframework.security.access.SecurityConfig;

import org.springframework.security.web.FilterInvocation;

import org.springframework.security.web.access.intercept.FilterInvocationSecurityMetadataSource;

import org.springframework.security.web.util.AntUrlPathMatcher;

import org.springframework.security.web.util.UrlMatcher;

/**

* 此类在初始化时，应该取到所有资源及其对应角色的定义

* @author Robin

public class MyInvocationSecurityMetadataSource

implements FilterInvocationSecurityMetadataSource {

private UrlMatcher urlMatcher = new AntUrlPathMatcher();;

private static Map<String, Collection<ConfigAttribute>> resourceMap = null;

public MyInvocationSecurityMetadataSource() {

loadResourceDefine();

}

private void loadResourceDefine() {

resourceMap = new HashMap<String, Collection<ConfigAttribute>>();

Collection<ConfigAttribute> atts = new ArrayList<ConfigAttribute>();

ConfigAttribute ca = new SecurityConfig("ROLE_ADMIN");

atts.add(ca);

resourceMap.put("/index.jsp", atts);

resourceMap.put("/i.jsp", atts);

}

// According to a URL, Find out permission configuration of this URL.

public Collection<ConfigAttribute> getAttributes(Object object)

throws IllegalArgumentException {

// guess object is a URL.

String url = ((FilterInvocation)object).getRequestUrl();

Iterator<String> ite = resourceMap.keySet().iterator();

while (ite.hasNext()) {

String resURL = ite.next();

if (urlMatcher.pathMatchesUrl(resURL, url)) {

return resourceMap.get(resURL);

}

return null;

}

public boolean supports(Class<?> clazz) {

return true;

}

public Collection<ConfigAttribute> getAllConfigAttributes() {

return null;

}

看看loadResourceDefine方法，我在这里，假定index.jsp和i.jsp这两个资源，需要ROLE_ADMIN角色的用户才能访问。
这个类中，还有一个最核心的地方，就是提供某个资源对应的权限定义，即getAttributes方法返回的结果。注意，我例子中使用的是AntUrlPathMatcher这个path matcher来检查URL是否与资源定义匹配，事实上你还要用正则的方式来匹配，或者自己实现一个matcher。

6，剩下的就是最终的决策了，make a decision，其实也很容易，呵呵。

package com.robin.erp.fwk.security;

import java.util.Collection;

import java.util.Iterator;

import org.springframework.security.access.AccessDecisionManager;

import org.springframework.security.access.AccessDeniedException;

import org.springframework.security.access.ConfigAttribute;

import org.springframework.security.access.SecurityConfig;

import org.springframework.security.authentication.InsufficientAuthenticationException;

import org.springframework.security.core.Authentication;

import org.springframework.security.core.GrantedAuthority;

public class MyAccessDecisionManager implements AccessDecisionManager {

//In this method, need to compare authentication with configAttributes.

// 1, A object is a URL, a filter was find permission configuration by this URL, and pass to here.

// 2, Check authentication has attribute in permission configuration (configAttributes)

// 3, If not match corresponding authentication, throw a AccessDeniedException.

public void decide(Authentication authentication, Object object,

Collection<ConfigAttribute> configAttributes)

throws AccessDeniedException, InsufficientAuthenticationException {

if(configAttributes == null){

return ;

}

System.out.println(object.toString()); //object is a URL.

Iterator<ConfigAttribute> ite=configAttributes.iterator();

while(ite.hasNext()){

ConfigAttribute ca=ite.next();

String needRole=((SecurityConfig)ca).getAttribute();

for(GrantedAuthority ga:authentication.getAuthorities()){

if(needRole.equals(ga.getAuthority())){ //ga is user's role.

return;

}

throw new AccessDeniedException("no right");

}

@Override

public boolean supports(ConfigAttribute attribute) {

// TODO Auto-generated method stub

return true;

}

@Override

public boolean supports(Class<?> clazz) {

return true;

}

在这个类中，最重要的是decide方法，如果不存在对该资源的定义，直接放行；否则，如果找到正确的角色，即认为拥有权限，并放行，否则throw new AccessDeniedException("no right");这样，就会进入上面提到的403.jsp页面。

参考资料：
1，Spring官方网站： http://www.springframework.org
2，文章所用的代码，MyEclipse工程，去掉了lib，请自行下载Spring Security 3.x的包，并copy至对应目录。工程源代码
3，根据网络上的资料，制作的CHM版的 Spring Security 3.x 参考手册中文版
4，2009年3月，我在“IBM WebSphere技术专家沙龙（华南区广州站）”演讲时的PPT：《Spring Security--Protect your web application》，当时是Spring Security 2.x，很多原理是一样，可作参考。

教程中为了尽可能不跟其它框架关联上，所以去掉了访问数据库的部分，比如用户信息和资源配置信息的读取，直接写死在代码中了，大家可以根据自己的实际情况补充完整。

如有任何疑问，欢迎大家以评论的方式提问，也欢迎大家讨论！