springsecurity与Acegi区别
搭建基础环境
首先我们为示例搭建基本的开发环境，环境的搭建方式，可以参考我的另外一篇文章：http://www.javaeye.com/wiki/struts2/1321-struts2-development-environment-to-build
整个环境的搭建包括：创建合适的目录结构、加入了合适的Library，加入了基本的Jetty启动类、加入基本的配置文件等。最终的项目结构，可以参考我的附件。
参考文档
这里主要的参考文档是Spring Security的自带的Reference。网络上有一个它的中文翻译，地址如下：http://www.family168.com/tutorial/springsecurity/html/springsecurity.html
除此之外，springside有一个比较完整的例子，不过是基于Acegi的，我也参阅了其中的一些实现。
Spring Security基本配置
Spring Security是基于Spring的的权限认证框架，对于Spring和Acegi已经比较熟悉的同学对于之前的配置方式应该已经非常了解。接下来的例子，将向大家展示Spring Security基于schema的配置方式。
最小化配置
1. 在web.xml文件中加入Filter声明
Xml代码
1. <!-- Spring security Filter -->
2. <filter>
3. <filter-name>springSecurityFilterChain</filter-name>
4. <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
5. </filter>
6. <filter-mapping>
7. <filter-name>springSecurityFilterChain</filter-name>
8. <url-pattern>/*</url-pattern>
9. </filter-mapping>
<!-- Spring security Filter -->
<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>
这个Filter会拦截所有的URL请求，并且对这些URL请求进行Spring Security的验证。
注意，springSecurityFilterChain这个名称是由命名空间默认创建的用于处理web安全的一个内部的bean的id。所以你在你的Spring配置文件中，不应该再使用这个id作为你的bean。
与Acegi的配置不同，Acegi需要自行声明一个Spring的bean来作为Filter的实现，而使用Spring Security后，无需再额外定义bean，而是使用<http>元素进行配置。
2. 使用最小的<http>配置
Xml代码
1. <http auto-config='true'>
2. <intercept-url pattern="/**" access="ROLE_USER" />
3. </http>
<http auto-config='true'>
<intercept-url pattern="/**" access="ROLE_USER" />
</http>
这段配置表示：我们要保护应用程序中的所有URL，只有拥有ROLE_USER角色的用户才能访问。你可以使用多个<intercept-url>元素为不同URL的集合定义不同的访问需求，它们会被归入一个有序队列中，每次取出最先匹配的一个元素使用。 所以你必须把期望使用的匹配条件放到最上边。
3. 配置UserDetailsService来指定用户和权限
接下来，我们来配置一个UserDetailsService来指定用户和权限：
Xml代码
1. <authentication-provider>
2. <user-service>
3. <user name="downpour" password="downpour" authorities="ROLE_USER, ROLE_ADMIN" />
4. <user name="robbin" password="robbin" authorities="ROLE_USER" />
5. <user name="QuakeWang" password="QuakeWang" authorities="ROLE_ADMIN" />
6. </user-service>
7. </authentication-provider>
<authentication-provider>
<user-service>
<user name="downpour" password="downpour" authorities="ROLE_USER, ROLE_ADMIN" />
<user name="robbin" password="robbin" authorities="ROLE_USER" />
<user name="QuakeWang" password="QuakeWang" authorities="ROLE_ADMIN" />
</user-service>
</authentication-provider>
在这里，downpour拥有ROLE_USER和ROLE_ADMIN的权限，robbin拥有ROLE_USER权限，QuakeWang拥有ROLE_ADMIN的权限
4. 小结
有了以上的配置，你已经可以跑简单的Spring Security的应用了。只不过在这里，我们还缺乏很多基本的元素，所以我们尚不能对上面的代码进行完整性测试。
如果你具备Acegi的知识，你会发现，有很多Acegi中的元素，在Spring Security中都没有了，这些元素包括：表单和基本登录选项、密码编码器、Remember-Me认证等等。
接下来，我们就来详细剖析一下Spring Security中的这些基本元素。
剖析基本配置元素
1. 有关auto-config属性
在上面用到的auto-config属性，其实是下面这些配置的缩写：
Xml代码
1. <http>
2. <intercept-url pattern="/**" access="ROLE_USER" />
3. <form-login />
4. <anonymous />
5. <http-basic />
6. <logout />
7. <remember-me />
8. </http>
<http>
<intercept-url pattern="/**" access="ROLE_USER" />
<form-login />
<anonymous />
<http-basic />
<logout />
<remember-me />
</http>
这些元素分别与登录认证，匿名认证，基本认证，注销处理和remember-me对应。 他们拥有各自的属性，可以改变他们的具体行为。
这样，我们在Acegi中所熟悉的元素又浮现在我们的面前。只是在这里，我们使用的是命名空间而已。
2. 与Acegi的比较
我们仔细观察一下没有auto-config的那段XML配置，是不是熟悉多了？让我们来将基于命名空间的配置与传统的Acegi的bean的配置做一个比较，我们会发现以下的区别：
1) 基于命名空间的配置更加简洁，可维护性更强
例如，基于命名空间进行登录认证的配置代码，可能像这样：
Xml代码
1. <form-login login-page="/login.jsp" authentication-failure-url="/login.jsp?error=true" default-target-url="/work" />
<form-login login-page="/login.jsp" authentication-failure-url="/login.jsp?error=true" default-target-url="/work" />
如果使用老的Acegi的Bean的定义方式，可能像这样：
Xml代码
1. <bean id="authenticationProcessingFilter"
2. class="org.acegisecurity.ui.webapp.AuthenticationProcessingFilter">
3. <property name="authenticationManager"
4. ref="authenticationManager"/>
5. <property name="authenticationFailureUrl"
6. value="/login.jsp?error=1"/>
7. <property name="defaultTargetUrl" value="/work"/>
8. <property name="filterProcessesUrl"
9. value="/j_acegi_security_check"/>
10. <property name="rememberMeServices" ref="rememberMeServices"/>
11. </bean>
<bean id="authenticationProcessingFilter"
class="org.acegisecurity.ui.webapp.AuthenticationProcessingFilter">
<property name="authenticationManager"
ref="authenticationManager"/>
<property name="authenticationFailureUrl"
value="/login.jsp?error=1"/>
<property name="defaultTargetUrl" value="/work"/>
<property name="filterProcessesUrl"
value="/j_acegi_security_check"/>
<property name="rememberMeServices" ref="rememberMeServices"/>
</bean>
这样的例子很多，有兴趣的读者可以一一进行比较。
2) 基于命名空间的配置，我们无需再担心由于过滤器链的顺序而导致的错误
以前，Acegi在缺乏默认内置配置的情况下，你需要自己来定义所有的bean，并指定这些bean在过滤器链中的顺序。一旦顺序错了，很容易发生错误。而现在，过滤器链的顺序被默认指定，你不需要在担心由于顺序的错误而导致的错误。
3. 过滤器链在哪里
到目前为止，我们都还没有讨论过整个Spring Security的核心部分：过滤器链。在原本Acegi的配置中，我们大概是这样配置我们的过滤器链的：
Xml代码
1. <bean id="filterChainProxy"
2. class="org.acegisecurity.util.FilterChainProxy">
3. <property name="filterInvocationDefinitionSource">
4. <value>
5. CONVERT_URL_TO_LOWERCASE_BEFORE_COMPARISON
6. PATTERN_TYPE_APACHE_ANT
7. /common/**=#NONE#
8. /css/**=#NONE#
9. /images/**=#NONE#
10. /js/**=#NONE#
11. /login.jsp=#NONE#
12. /**=httpSessionContextIntegrationFilter,logoutFilter,authenticationProcessingFilter,securityContextHolderAwareRequestFilter,exceptionTranslationFilter,filterSecurityInterceptor
13. </value>
14. </property>
15. </bean>
<bean id="filterChainProxy"
class="org.acegisecurity.util.FilterChainProxy">
<property name="filterInvocationDefinitionSource">
<value>
CONVERT_URL_TO_LOWERCASE_BEFORE_COMPARISON
PATTERN_TYPE_APACHE_ANT
/common/**=#NONE#
/css/**=#NONE#
/images/**=#NONE#
/js/**=#NONE#
/login.jsp=#NONE#
/**=httpSessionContextIntegrationFilter,logoutFilter,authenticationProcessingFilter,securityContextHolderAwareRequestFilter,exceptionTranslationFilter,filterSecurityInterceptor
</value>
</property>
</bean>
其中，每个过滤器链都将对应于Spring配置文件中的bean的id。
现在，在Spring Security中，我们将看不到这些配置，这些配置都被内置在<http>节点中。让我们来看看这些默认的，已经被内置的过滤器：
这些过滤器已经被Spring容器默认内置注册，这也就是我们不再需要在配置文件中定义那么多bean的原因。
同时，过滤器顺序在使用命名空间的时候是被严格执行的。它们在初始化的时候就预先被排好序。不仅如此，Spring Security规定，你不能替换那些<http>元素自己使用而创建出的过滤器，比如HttpSessionContextIntegrationFilter, ExceptionTranslationFilter 或 FilterSecurityInterceptor。
当然，这样的规定是否合理，有待进一步讨论。因为实际上在很多时候，我们希望覆盖过滤器链中的某个过滤器的默认行为。而Spring Security的这种规定在一定程度上限制了我们的行为。
不过Spring Security允许你把你自己的过滤器添加到队列中，使用custom-filter元素，并且指定你的过滤器应该出现的位置：
Xml代码
1. <beans:bean id="myFilter" class="com.mycompany.MySpecialAuthenticationFilter">
2. <custom-filter position="AUTHENTICATION_PROCESSING_FILTER"/>
3. </beans:bean>
<beans:bean id="myFilter" class="com.mycompany.MySpecialAuthenticationFilter">
<custom-filter position="AUTHENTICATION_PROCESSING_FILTER"/>
</beans:bean>
不仅如此，你还可以使用after或before属性，如果你想把你的过滤器添加到队列中另一个过滤器的前面或后面。 可以分别在position属性使用"FIRST"或"LAST"来指定你想让你的过滤器出现在队列元素的前面或后面。
这个特性或许能够在一定程度上弥补Spring Security的死板规定，而在之后的应用中，我也会把它作为切入点，对资源进行管理。
另外，我需要补充一点的是，对于在http/intercept-url中没有进行定义的URL，将会默认使用系统内置的过滤器链进行权限认证。所以，你并不需要在http/intercept-url中额外定义一个类似/**的匹配规则。
使用数据库对用户和权限进行管理
一般来说，我们都有使用数据库对用户和权限进行管理的需求，而不会把用户写死在配置文件里。所以，我们接下来就重点讨论使用数据库对用户和权限进行管理的方法。
用户和权限的关系设计
在此之前，我们首先需要讨论一下用户（User）和权限（Role）之间的关系。Spring Security在默认情况下，把这两者当作一对多的关系进行处理。所以，在Spring Security中对这两个对象所采用的表结构关系大概像这样：
Java代码
1. CREATE TABLE users (
2. username VARCHAR(50) NOT NULL PRIMARY KEY,
3. password VARCHAR(50) NOT NULL,
4. enabled BIT NOT NULL
5. );
6.
7. CREATE TABLE authorities (
8. username VARCHAR(50) NOT NULL,
9. authority VARCHAR(50) NOT NULL
10. );
CREATE TABLE users (
username VARCHAR(50) NOT NULL PRIMARY KEY,
password VARCHAR(50) NOT NULL,
enabled BIT NOT NULL
);
CREATE TABLE authorities (
username VARCHAR(50) NOT NULL,
authority VARCHAR(50) NOT NULL
);
不过这种设计方式在实际生产环境中基本上不会采用。一般来说，我们会使用逻辑主键ID来标示每个User和每个Authorities（Role）。而且从典型意义上讲，他们之间是一个多对多的关系，我们会采用3张表来表示，下面是我在MySQL中建立的3张表的schema示例：
Java代码
1. CREATE TABLE `user` (
2. `id` int(11) NOT NULL auto_increment,
3. `name` varchar(255) default NULL,
4. `password` varchar(255) default NULL,
5. `disabled` int(1) NOT NULL,
6. PRIMARY KEY (`id`)
7. ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
8.
9. CREATE TABLE `role` (
10. `id` int(11) NOT NULL auto_increment,
11. `name` varchar(255) default NULL,
12. PRIMARY KEY (`id`)
13. ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
14.
15. CREATE TABLE `user_role` (
16. `user_id` int(11) NOT NULL,
17. `role_id` int(11) NOT NULL,
18. PRIMARY KEY (`user_id`,`role_id`),
19. UNIQUE KEY `role_id` (`role_id`),
20. KEY `FK143BF46AF6AD4381` (`user_id`),
21. KEY `FK143BF46A51827FA1` (`role_id`),
22. CONSTRAINT `FK143BF46A51827FA1` FOREIGN KEY (`role_id`) REFERENCES `role` (`id`),
23. CONSTRAINT `FK143BF46AF6AD4381` FOREIGN KEY (`user_id`) REFERENCES `user` (`id`)
24. ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `user` (
`id` int(11) NOT NULL auto_increment,
`name` varchar(255) default NULL,
`password` varchar(255) default NULL,
`disabled` int(1) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `role` (
`id` int(11) NOT NULL auto_increment,
`name` varchar(255) default NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `user_role` (
`user_id` int(11) NOT NULL,
`role_id` int(11) NOT NULL,
PRIMARY KEY (`user_id`,`role_id`),
UNIQUE KEY `role_id` (`role_id`),
KEY `FK143BF46AF6AD4381` (`user_id`),
KEY `FK143BF46A51827FA1` (`role_id`),
CONSTRAINT `FK143BF46A51827FA1` FOREIGN KEY (`role_id`) REFERENCES `role` (`id`),
CONSTRAINT `FK143BF46AF6AD4381` FOREIGN KEY (`user_id`) REFERENCES `user` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
通过配置SQL来模拟用户和权限
有了数据库的表设计，我们就可以在Spring Security中，通过配置SQL，来模拟用户和权限，这依然通过<authentication-provider>来完成：
Xml代码
1. <authentication-provider>
2. <jdbc-user-service data-source-ref="dataSource"
3. users-by-username-query="SELECT U.username, U.password, U.accountEnabled AS 'enabled' FROM User U where U.username=?"
4. authorities-by-username-query="SELECT U.username, R.name as 'authority' FROM User U JOIN Authority A ON u.id = A.userId JOIN Role R ON R.id = A.roleId WHERE U.username=?"/>
5. </authentication-provider>
<authentication-provider>
<jdbc-user-service data-source-ref="dataSource"
users-by-username-query="SELECT U.username, U.password, U.accountEnabled AS 'enabled' FROM User U where U.username=?"
authorities-by-username-query="SELECT U.username, R.name as 'authority' FROM User U JOIN Authority A ON u.id = A.userId JOIN Role R ON R.id = A.roleId WHERE U.username=?"/>
</authentication-provider>
这里给出的是一个使用SQL进行模拟用户和权限的示例。其中你需要为运行SQL准备相应的dataSource。这个dataSource应该对应于Spring中的某个bean的定义。
从这段配置模拟用户和权限的情况来看，实际上Spring Security对于用户，需要username，password，accountEnabled三个字段。对于权限，它需要的是username和authority2个字段。
也就是说，如果我们能够通过其他的方式，模拟上面的这些对象，并插入到Spring Security中去，我们同样能够实现用户和权限的认证。接下来，我们就来看看我们如何通过自己的实现，来完成这件事情。
通过扩展Spring Security的默认实现来进行用户和权限的管理
事实上，Spring Security提供了2个认证的接口，分别用于模拟用户和权限，以及读取用户和权限的操作方法。这两个接口分别是：UserDetails和UserDetailsService。
Java代码
1. public interface UserDetails extends Serializable {
2.
3. GrantedAuthority[] getAuthorities();
4.
5. String getPassword();
6.
7. String getUsername();
8.
9. boolean isAccountNonExpired();
10.
11. boolean isAccountNonLocked();
12.
13. boolean isCredentialsNonExpired();
14.
15. boolean isEnabled();
16. }
public interface UserDetails extends Serializable {
GrantedAuthority[] getAuthorities();
String getPassword();
String getUsername();
boolean isAccountNonExpired();
boolean isAccountNonLocked();
boolean isCredentialsNonExpired();
boolean isEnabled();
}
Java代码
1. public interface UserDetailsService {
2. UserDetails loadUserByUsername(String username)
3. throws UsernameNotFoundException, DataAccessException;
4. }
public interface UserDetailsService {
UserDetails loadUserByUsername(String username)
throws UsernameNotFoundException, DataAccessException;
}
非常清楚，一个接口用于模拟用户，另外一个用于模拟读取用户的过程。所以我们可以通过实现这两个接口，来完成使用数据库对用户和权限进行管理的需求。在这里，我将给出一个使用Hibernate来定义用户和权限之间关系的示例。
1. 定义User类和Role类，使他们之间形成多对多的关系
Java代码
1. @Entity
2. @Proxy(lazy = false)
3. @Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
4. public class User {
5.
6. private static final long serialVersionUID = 8026813053768023527L;
7.
8. @Id
9. @GeneratedValue
10. private Integer id;
11.
12. private String name;
13.
14. private String password;
15.
16. private boolean disabled;
17.
18. @ManyToMany(targetEntity = Role.class, fetch = FetchType.EAGER)
19. @JoinTable(name = "user_role", joinColumns = @JoinColumn(name = "user_id"), inverseJoinColumns = @JoinColumn(name = "role_id"))
20. @Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
21. private Set<Role> roles;
22.
23. // setters and getters
24. }
@Entity
@Proxy(lazy = false)
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
public class User {
private static final long serialVersionUID = 8026813053768023527L;
@Id
@GeneratedValue
private Integer id;
private String name;
private String password;
private boolean disabled;
@ManyToMany(targetEntity = Role.class, fetch = FetchType.EAGER)
@JoinTable(name = "user_role", joinColumns = @JoinColumn(name = "user_id"), inverseJoinColumns = @JoinColumn(name = "role_id"))
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
private Set<Role> roles;
// setters and getters
}
Java代码
1. @Entity
2. @Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
3. public class Role {
4.
5. @Id
6. @GeneratedValue
7. private Integer id;
8.
9. private String name;
10.
11. // setters and getters
12. }
@Entity
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
public class Role {
@Id
@GeneratedValue
private Integer id;
private String name;
// setters and getters
}
请注意这里的Annotation的写法。同时，我为User和Role之间配置了缓存。并且将他们之间的关联关系设置的lazy属性设置成false，从而保证在User对象取出之后的使用不会因为脱离session的生命周期而产生lazy loading问题。
2. 使User类实现UserDetails接口
接下来，我们让User类去实现UserDetails接口：
Java代码
1. @Entity
2. @Proxy(lazy = false)
3. @Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
4. public class User implements UserDetails {
5.
6. private static final long serialVersionUID = 8026813053768023527L;
7.
8. @Id
9. @GeneratedValue
10. private Integer id;
11.
12. private String name;
13.
14. private String password;
15.
16. private boolean disabled;
17.
18. @ManyToMany(targetEntity = Role.class, fetch = FetchType.EAGER)
19. @JoinTable(name = "user_role", joinColumns = @JoinColumn(name = "user_id"), inverseJoinColumns = @JoinColumn(name = "role_id"))
20. @Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
21. private Set<Role> roles;
22.
23. /**
24. * The default constructor
25. */
26. public User() {
27.
28. }
29.
30. /* (non-Javadoc)
31. * @see org.springframework.security.userdetails.UserDetails#getAuthorities()
32. */
33. public GrantedAuthority[] getAuthorities() {
34. List<GrantedAuthority> grantedAuthorities = new ArrayList<GrantedAuthority>(roles.size());
35. for(Role role : roles) {
36. grantedAuthorities.add(new GrantedAuthorityImpl(role.getName()));
37. }
38. return grantedAuthorities.toArray(new GrantedAuthority[roles.size()]);
39. }
40.
41. /* (non-Javadoc)
42. * @see org.springframework.security.userdetails.UserDetails#getPassword()
43. */
44. public String getPassword() {
45. return password;
46. }
47.
48. /* (non-Javadoc)
49. * @see org.springframework.security.userdetails.UserDetails#getUsername()
50. */
51. public String getUsername() {
52. return name;
53. }
54.
55. /* (non-Javadoc)
56. * @see org.springframework.security.userdetails.UserDetails#isAccountNonExpired()
57. */
58. public boolean isAccountNonExpired() {
59. return true;
60. }
61.
62. /* (non-Javadoc)
63. * @see org.springframework.security.userdetails.UserDetails#isAccountNonLocked()
64. */
65. public boolean isAccountNonLocked() {
66. return true;
67. }
68.
69. /* (non-Javadoc)
70. * @see org.springframework.security.userdetails.UserDetails#isCredentialsNonExpired()
71. */
72. public boolean isCredentialsNonExpired() {
73. return true;
74. }
75.
76. /* (non-Javadoc)
77. * @see org.springframework.security.userdetails.UserDetails#isEnabled()
78. */
79. public boolean isEnabled() {
80. return !this.disabled;
81. }
82.
83. // setters and getters
84. }
@Entity
@Proxy(lazy = false)
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
public class User implements UserDetails {
private static final long serialVersionUID = 8026813053768023527L;
@Id
@GeneratedValue
private Integer id;
private String name;
private String password;
private boolean disabled;
@ManyToMany(targetEntity = Role.class, fetch = FetchType.EAGER)
@JoinTable(name = "user_role", joinColumns = @JoinColumn(name = "user_id"), inverseJoinColumns = @JoinColumn(name = "role_id"))
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
private Set<Role> roles;
/**
* The default constructor
*/
public User() {
}
/* (non-Javadoc)
* @see org.springframework.security.userdetails.UserDetails#getAuthorities()
*/
public GrantedAuthority[] getAuthorities() {
List<GrantedAuthority> grantedAuthorities = new ArrayList<GrantedAuthority>(roles.size());
for(Role role : roles) {
grantedAuthorities.add(new GrantedAuthorityImpl(role.getName()));
}
return grantedAuthorities.toArray(new GrantedAuthority[roles.size()]);
}
/* (non-Javadoc)
* @see org.springframework.security.userdetails.UserDetails#getPassword()
*/
public String getPassword() {
return password;
}
/* (non-Javadoc)
* @see org.springframework.security.userdetails.UserDetails#getUsername()
*/
public String getUsername() {
return name;
}
/* (non-Javadoc)
* @see org.springframework.security.userdetails.UserDetails#isAccountNonExpired()
*/
public boolean isAccountNonExpired() {
return true;
}
/* (non-Javadoc)
* @see org.springframework.security.userdetails.UserDetails#isAccountNonLocked()
*/
public boolean isAccountNonLocked() {
return true;
}
/* (non-Javadoc)
* @see org.springframework.security.userdetails.UserDetails#isCredentialsNonExpired()
*/
public boolean isCredentialsNonExpired() {
return true;
}
/* (non-Javadoc)
* @see org.springframework.security.userdetails.UserDetails#isEnabled()
*/
public boolean isEnabled() {
return !this.disabled;
}
// setters and getters
}
实现UserDetails接口中的每个函数，其实没什么很大的难度，除了其中的一个函数我需要额外强调一下：
Java代码
1. /* (non-Javadoc)
2. * @see org.springframework.security.userdetails.UserDetails#getAuthorities()
3. */
4. public GrantedAuthority[] getAuthorities() {
5. List<GrantedAuthority> grantedAuthorities = new ArrayList<GrantedAuthority>(roles.size());
6. for(Role role : roles) {
7. grantedAuthorities.add(new GrantedAuthorityImpl(role.getName()));
8. }
9. return grantedAuthorities.toArray(new GrantedAuthority[roles.size()]);
10. }
/* (non-Javadoc)
* @see org.springframework.security.userdetails.UserDetails#getAuthorities()
*/
public GrantedAuthority[] getAuthorities() {
List<GrantedAuthority> grantedAuthorities = new ArrayList<GrantedAuthority>(roles.size());
for(Role role : roles) {
grantedAuthorities.add(new GrantedAuthorityImpl(role.getName()));
}
return grantedAuthorities.toArray(new GrantedAuthority[roles.size()]);
}
这个函数的实际作用是根据User返回这个User所拥有的权限列表。如果以上面曾经用过的例子来说，如果当前User是downpour，我需要得到ROLE_USER和ROLE_ADMIN；如果当前User是robbin，我需要得到ROLE_USER。
了解了含义，实现就变得简单了，由于User与Role是多对多的关系，我们可以通过User得到所有这个User所对应的Role，并把这些Role的name拼装起来返回。
由此可见，实现UserDetails接口，并没有什么神秘的地方，它只是实际上在一定程度上只是代替了使用配置文件的硬编码：
Xml代码
1. <user name="downpour" password="downpour" authorities="ROLE_USER, ROLE_ADMIN" />
<user name="downpour" password="downpour" authorities="ROLE_USER, ROLE_ADMIN" />
3. 实现UserDetailsService接口
Java代码
1. @Repository("securityManager")
2. public class SecurityManagerSupport extends HibernateDaoSupport implements UserDetailsService {
3.
4. /**
5. * Init sessionFactory here because the annotation of Spring 2.5 can not support override inject
6. *
7. * @param sessionFactory
8. */
9. @Autowired
10. public void init(SessionFactory sessionFactory) {
11. super.setSessionFactory(sessionFactory);
12. }
13.
14. public UserDetails loadUserByUsername(String userName) throws UsernameNotFoundException, DataAccessException {
15. List<User> users = getHibernateTemplate().find("FROM User user WHERE user.name = ? AND user.disabled = false", userName);
16. if(users.isEmpty()) {
17. throw new UsernameNotFoundException("User " + userName + " has no GrantedAuthority");
18. }
19. return users.get(0);
20. }
21. }
@Repository("securityManager")
public class SecurityManagerSupport extends HibernateDaoSupport implements UserDetailsService {
/**
* Init sessionFactory here because the annotation of Spring 2.5 can not support override inject
*
* @param sessionFactory
*/
@Autowired
public void init(SessionFactory sessionFactory) {
super.setSessionFactory(sessionFactory);
}
public UserDetails loadUserByUsername(String userName) throws UsernameNotFoundException, DataAccessException {
List<User> users = getHibernateTemplate().find("FROM User user WHERE user.name = ? AND user.disabled = false", userName);
if(users.isEmpty()) {
throw new UsernameNotFoundException("User " + userName + " has no GrantedAuthority");
}
return users.get(0);
}
}
这个实现非常简单，由于我们的User对象已经实现了UserDetails接口。所以我们只要使用Hibernate，根据userName取出相应的User对象即可。注意在这里，由于我们对于User的关联对象Roles都设置了lazy="false"，所以我们无需担心lazy loading的问题。
4. 配置文件
有了上面的代码，一切都变得很简单，重新定义authentication-provider节点即可。如果你使用Spring 2.5的Annotation配置功能，你甚至可以不需要在配置文件中定义securityManager的bean。
Xml代码
1. <authentication-provider user-service-ref="securityManager">
2. <password-encoder hash="md5"/>
3. </authentication-provider>
<authentication-provider user-service-ref="securityManager">
<password-encoder hash="md5"/>
</authentication-provider>
使用数据库对资源进行管理
在完成了使用数据库来进行用户和权限的管理之后，我们再来看看http配置的部分。在实际应用中，我们不可能使用类似/**的方式来指定URL与权限ROLE的对应关系，而是会针对某些URL，指定某些特定的ROLE。而URL与ROLE之间的映射关系最好可以进行扩展和配置。而URL属于资源的一种，所以接下来，我们就来看看如何使用数据库来对权限和资源的匹配关系进行管理，并且将认证匹配加入到Spring Security中去。
权限和资源的设计
上面我们讲到，用户（User）和权限（Role）之间是一个多对多的关系。那么权限（Role）和资源（Resource）之间呢？其实他们之间也是一个典型的多对多的关系，我们同样用3张表来表示：
Java代码
1. CREATE TABLE `role` (
2. `id` int(11) NOT NULL auto_increment,
3. `name` varchar(255) default NULL,
4. `description` varchar(255) default NULL,
5. PRIMARY KEY (`id`)
6. ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
7.
8. CREATE TABLE `resource` (
9. `id` int(11) NOT NULL auto_increment,
10. `type` varchar(255) default NULL,
11. `value` varchar(255) default NULL,
12. PRIMARY KEY (`id`)
13. ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
14.
15. CREATE TABLE `role_resource` (
16. `role_id` int(11) NOT NULL,
17. `resource_id` int(11) NOT NULL,
18. PRIMARY KEY (`role_id`,`resource_id`),
19. KEY `FKAEE599B751827FA1` (`role_id`),
20. KEY `FKAEE599B7EFD18D21` (`resource_id`),
21. CONSTRAINT `FKAEE599B751827FA1` FOREIGN KEY (`role_id`) REFERENCES `role` (`id`),
22. CONSTRAINT `FKAEE599B7EFD18D21` FOREIGN KEY (`resource_id`) REFERENCES `resource` (`id`)
23. ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `role` (
`id` int(11) NOT NULL auto_increment,
`name` varchar(255) default NULL,
`description` varchar(255) default NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `resource` (
`id` int(11) NOT NULL auto_increment,
`type` varchar(255) default NULL,
`value` varchar(255) default NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `role_resource` (
`role_id` int(11) NOT NULL,
`resource_id` int(11) NOT NULL,
PRIMARY KEY (`role_id`,`resource_id`),
KEY `FKAEE599B751827FA1` (`role_id`),
KEY `FKAEE599B7EFD18D21` (`resource_id`),
CONSTRAINT `FKAEE599B751827FA1` FOREIGN KEY (`role_id`) REFERENCES `role` (`id`),
CONSTRAINT `FKAEE599B7EFD18D21` FOREIGN KEY (`resource_id`) REFERENCES `resource` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
在这里Resource可能分成多种类型，比如MENU,URL,METHOD等等。
针对资源的认证
针对资源的认证，实际上应该由Spring Security中的FilterSecurityInterceptor这个过滤器来完成。不过内置的FilterSecurityInterceptor的实现往往无法满足我们的要求，所以传统的Acegi的方式，我们往往会替换FilterSecurityInterceptor的实现，从而对URL等资源进行认证。
不过在Spring Security中，由于默认的拦截器链内置了FilterSecurityInterceptor，而且上面我们也提到过，这个实现无法被替换。这就使我们犯了难。我们如何对资源进行认证呢？
实际上，我们虽然无法替换FilterSecurityInterceptor的默认实现，不过我们可以再实现一个类似的过滤器，并将我们自己的过滤器作为一个customer-filter，加到默认的过滤器链的最后，从而完成整个过滤检查。
接下来我们就来看看一个完整的例子：
1. 建立权限（Role）和资源（Resource）之间的关联关系
修改上面的权限（Role）的Entity定义：
Java代码
1. @Entity
2. @Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
3. public class Role {
4.
5. @Id
6. @GeneratedValue
7. private Integer id;
8.
9. private String name;
10.
11. @ManyToMany(targetEntity = Resource.class, fetch = FetchType.EAGER)
12. @JoinTable(name = "role_resource", joinColumns = @JoinColumn(name = "role_id"), inverseJoinColumns = @JoinColumn(name = "resource_id"))
13. @Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
14. private Set<Resource> resources;
15.
16. // setters and getter
17. }
@Entity
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
public class Role {
@Id
@GeneratedValue
private Integer id;
private String name;
@ManyToMany(targetEntity = Resource.class, fetch = FetchType.EAGER)
@JoinTable(name = "role_resource", joinColumns = @JoinColumn(name = "role_id"), inverseJoinColumns = @JoinColumn(name = "resource_id"))
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
private Set<Resource> resources;
// setters and getter
}
增加资源（Resource）的Entity定义：
Java代码
1. @Entity
2. @Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
3.
4. public class Resource {
5.
6. @Id
7. @GeneratedValue
8. private Integer id;
9.
10. private String type;
11.
12. private String value;
13.
14. @ManyToMany(mappedBy = "resources", targetEntity = Role.class, fetch = FetchType.EAGER)
15. @Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
16. private Set<Role> roles;
17.
18. /**
19. * The default constructor
20. */
21. public Resource() {
22.
23. }
24. }
@Entity
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
public class Resource {
@Id
@GeneratedValue
private Integer id;
private String type;
private String value;
@ManyToMany(mappedBy = "resources", targetEntity = Role.class, fetch = FetchType.EAGER)
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
private Set<Role> roles;
/**
* The default constructor
*/
public Resource() {
}
}
注意他们之间的多对多关系，以及他们之间关联关系的缓存和lazy属性设置。
2. 在系统启动的时候，把所有的资源load到内存作为缓存
由于资源信息对于每个项目来说，相对固定，所以我们可以将他们在系统启动的时候就load到内存作为缓存。这里做法很多，我给出的示例是将资源的存放在servletContext中。
Java代码
1. public class ServletContextLoaderListener implements ServletContextListener {
2.
3. /* (non-Javadoc)
4. * @see javax.servlet.ServletContextListener#contextInitialized(javax.servlet.ServletContextEvent)
5. */
6. public void contextInitialized(ServletContextEvent servletContextEvent) {
7. ServletContext servletContext = servletContextEvent.getServletContext();
8. SecurityManager securityManager = this.getSecurityManager(servletContext);
9.
10. Map<String, String> urlAuthorities = securityManager.loadUrlAuthorities();
11. servletContext.setAttribute("urlAuthorities", urlAuthorities);
12. }
13.
14.
15. /* (non-Javadoc)
16. * @see javax.servlet.ServletContextListener#contextDestroyed(javax.servlet.ServletContextEvent)
17. */
18. public void contextDestroyed(ServletContextEvent servletContextEvent) {
19. servletContextEvent.getServletContext().removeAttribute("urlAuthorities");
20. }
21.
22. /**
23. * Get SecurityManager from ApplicationContext
24. *
25. * @param servletContext
26. * @return
27. */
28. protected SecurityManager getSecurityManager(ServletContext servletContext) {
29. return (SecurityManager) WebApplicationContextUtils.getWebApplicationContext(servletContext).getBean("securityManager");
30. }
31.
32. }
public class ServletContextLoaderListener implements ServletContextListener {
/* (non-Javadoc)
* @see javax.servlet.ServletContextListener#contextInitialized(javax.servlet.ServletContextEvent)
*/
public void contextInitialized(ServletContextEvent servletContextEvent) {
ServletContext servletContext = servletContextEvent.getServletContext();
SecurityManager securityManager = this.getSecurityManager(servletContext);
Map<String, String> urlAuthorities = securityManager.loadUrlAuthorities();
servletContext.setAttribute("urlAuthorities", urlAuthorities);
}
/* (non-Javadoc)
* @see javax.servlet.ServletContextListener#contextDestroyed(javax.servlet.ServletContextEvent)
*/
public void contextDestroyed(ServletContextEvent servletContextEvent) {
servletContextEvent.getServletContext().removeAttribute("urlAuthorities");
}
/**
* Get SecurityManager from ApplicationContext
*
* @param servletContext
* @return
*/
protected SecurityManager getSecurityManager(ServletContext servletContext) {
return (SecurityManager) WebApplicationContextUtils.getWebApplicationContext(servletContext).getBean("securityManager");
}
}
这里，我们看到了SecurityManager，这是一个接口，用于权限相关的逻辑处理。还记得之前我们使用数据库管理User的时候所使用的一个实现类SecurityManagerSupport嘛？我们不妨依然借用这个类，让它实现SecurityManager接口，来同时完成url的读取工作。
Java代码
1. @Service("securityManager")
2. public class SecurityManagerSupport extends HibernateDaoSupport implements UserDetailsService, SecurityManager {
3.
4. /**
5. * Init sessionFactory here because the annotation of Spring 2.5 can not support override inject
6. *
7. * @param sessionFactory
8. */
9. @Autowired
10. public void init(SessionFactory sessionFactory) {
11. super.setSessionFactory(sessionFactory);
12. }
13.
14. /* (non-Javadoc)
15. * @see org.springframework.security.userdetails.UserDetailsService#loadUserByUsername(java.lang.String)
16. */
17. public UserDetails loadUserByUsername(String userName) throws UsernameNotFoundException, DataAccessException {
18. List<User> users = getHibernateTemplate().find("FROM User user WHERE user.name = ? AND user.disabled = false", userName);
19. if(users.isEmpty()) {
20. throw new UsernameNotFoundException("User " + userName + " has no GrantedAuthority");
21. }
22. return users.get(0);
23. }
24.
25. /* (non-Javadoc)
26. * @see com.javaeye.sample.security.SecurityManager#loadUrlAuthorities()
27. */
28. public Map<String, String> loadUrlAuthorities() {
29. Map<String, String> urlAuthorities = new HashMap<String, String>();
30. List<Resource> urlResources = getHibernateTemplate().find("FROM Resource resource WHERE resource.type = ?", "URL");
31. for(Resource resource : urlResources) {
32. urlAuthorities.put(resource.getValue(), resource.getRoleAuthorities());
33. }
34. return urlAuthorities;
35. }
36. }
@Service("securityManager")
public class SecurityManagerSupport extends HibernateDaoSupport implements UserDetailsService, SecurityManager {
/**
* Init sessionFactory here because the annotation of Spring 2.5 can not support override inject
*
* @param sessionFactory
*/
@Autowired
public void init(SessionFactory sessionFactory) {
super.setSessionFactory(sessionFactory);
}
/* (non-Javadoc)
* @see org.springframework.security.userdetails.UserDetailsService#loadUserByUsername(java.lang.String)
*/
public UserDetails loadUserByUsername(String userName) throws UsernameNotFoundException, DataAccessException {
List<User> users = getHibernateTemplate().find("FROM User user WHERE user.name = ? AND user.disabled = false", userName);
if(users.isEmpty()) {
throw new UsernameNotFoundException("User " + userName + " has no GrantedAuthority");
}
return users.get(0);
}
/* (non-Javadoc)
* @see com.javaeye.sample.security.SecurityManager#loadUrlAuthorities()
*/
public Map<String, String> loadUrlAuthorities() {
Map<String, String> urlAuthorities = new HashMap<String, String>();
List<Resource> urlResources = getHibernateTemplate().find("FROM Resource resource WHERE resource.type = ?", "URL");
for(Resource resource : urlResources) {
urlAuthorities.put(resource.getValue(), resource.getRoleAuthorities());
}
return urlAuthorities;
}
}
3. 编写自己的FilterInvocationDefinitionSource实现类，对资源进行认证
Java代码
1. public class SecureResourceFilterInvocationDefinitionSource implements FilterInvocationDefinitionSource, InitializingBean {
2.
3. private UrlMatcher urlMatcher;
4.
5. private boolean useAntPath = true;
6.
7. private boolean lowercaseComparisons = true;
8.
9. /**
10. * @param useAntPath the useAntPath to set
11. */
12. public void setUseAntPath(boolean useAntPath) {
13. this.useAntPath = useAntPath;
14. }
15.
16. /**
17. * @param lowercaseComparisons
18. */
19. public void setLowercaseComparisons(boolean lowercaseComparisons) {
20. this.lowercaseComparisons = lowercaseComparisons;
21. }
22.
23. /* (non-Javadoc)
24. * @see org.springframework.beans.factory.InitializingBean#afterPropertiesSet()
25. */
26. public void afterPropertiesSet() throws Exception {
27.
28. // default url matcher will be RegexUrlPathMatcher
29. this.urlMatcher = new RegexUrlPathMatcher();
30.
31. if (useAntPath) { // change the implementation if required
32. this.urlMatcher = new AntUrlPathMatcher();
33. }
34.
35. // Only change from the defaults if the attribute has been set
36. if ("true".equals(lowercaseComparisons)) {
37. if (!this.useAntPath) {
38. ((RegexUrlPathMatcher) this.urlMatcher).setRequiresLowerCaseUrl(true);
39. }
40. } else if ("false".equals(lowercaseComparisons)) {
41. if (this.useAntPath) {
42. ((AntUrlPathMatcher) this.urlMatcher).setRequiresLowerCaseUrl(false);
43. }
44. }
45.
46. }
47.
48. /* (non-Javadoc)
49. * @see org.springframework.security.intercept.ObjectDefinitionSource#getAttributes(java.lang.Object)
50. */
51. public ConfigAttributeDefinition getAttributes(Object filter) throws IllegalArgumentException {
52.
53. FilterInvocation filterInvocation = (FilterInvocation) filter;
54. String requestURI = filterInvocation.getRequestUrl();
55. Map<String, String> urlAuthorities = this.getUrlAuthorities(filterInvocation);
56.
57. String grantedAuthorities = null;
58. for(Iterator<Map.Entry<String, String>> iter = urlAuthorities.entrySet().iterator(); iter.hasNext();) {
59. Map.Entry<String, String> entry = iter.next();
60. String url = entry.getKey();
61.
62. if(urlMatcher.pathMatchesUrl(url, requestURI)) {
63. grantedAuthorities = entry.getValue();
64. break;
65. }
66.
67. }
68.
69. if(grantedAuthorities != null) {
70. ConfigAttributeEditor configAttrEditor = new ConfigAttributeEditor();
71. configAttrEditor.setAsText(grantedAuthorities);
72. return (ConfigAttributeDefinition) configAttrEditor.getValue();
73. }
74.
75. return null;
76. }
77.
78. /* (non-Javadoc)
79. * @see org.springframework.security.intercept.ObjectDefinitionSource#getConfigAttributeDefinitions()
80. */
81. @SuppressWarnings("unchecked")
82. public Collection getConfigAttributeDefinitions() {
83. return null;
84. }
85.
86. /* (non-Javadoc)
87. * @see org.springframework.security.intercept.ObjectDefinitionSource#supports(java.lang.Class)
88. */
89. @SuppressWarnings("unchecked")
90. public boolean supports(Class clazz) {
91. return true;
92. }
93.
94. /**
95. *
96. * @param filterInvocation
97. * @return
98. */
99. @SuppressWarnings("unchecked")
100. private Map<String, String> getUrlAuthorities(FilterInvocation filterInvocation) {
101. ServletContext servletContext = filterInvocation.getHttpRequest().getSession().getServletContext();
102. return (Map<String, String>)servletContext.getAttribute("urlAuthorities");
103. }
104.
105. }
public class SecureResourceFilterInvocationDefinitionSource implements FilterInvocationDefinitionSource, InitializingBean {
private UrlMatcher urlMatcher;
private boolean useAntPath = true;
private boolean lowercaseComparisons = true;
/**
* @param useAntPath the useAntPath to set
*/
public void setUseAntPath(boolean useAntPath) {
this.useAntPath = useAntPath;
}
/**
* @param lowercaseComparisons
*/
public void setLowercaseComparisons(boolean lowercaseComparisons) {
this.lowercaseComparisons = lowercaseComparisons;
}
/* (non-Javadoc)
* @see org.springframework.beans.factory.InitializingBean#afterPropertiesSet()
*/
public void afterPropertiesSet() throws Exception {
// default url matcher will be RegexUrlPathMatcher
this.urlMatcher = new RegexUrlPathMatcher();
if (useAntPath) { // change the implementation if required
this.urlMatcher = new AntUrlPathMatcher();
}
// Only change from the defaults if the attribute has been set
if ("true".equals(lowercaseComparisons)) {
if (!this.useAntPath) {
((RegexUrlPathMatcher) this.urlMatcher).setRequiresLowerCaseUrl(true);
}
} else if ("false".equals(lowercaseComparisons)) {
if (this.useAntPath) {
((AntUrlPathMatcher) this.urlMatcher).setRequiresLowerCaseUrl(false);
}
}
}
/* (non-Javadoc)
* @see org.springframework.security.intercept.ObjectDefinitionSource#getAttributes(java.lang.Object)
*/
public ConfigAttributeDefinition getAttributes(Object filter) throws IllegalArgumentException {
FilterInvocation filterInvocation = (FilterInvocation) filter;
String requestURI = filterInvocation.getRequestUrl();
Map<String, String> urlAuthorities = this.getUrlAuthorities(filterInvocation);
String grantedAuthorities = null;
for(Iterator<Map.Entry<String, String>> iter = urlAuthorities.entrySet().iterator(); iter.hasNext();) {
Map.Entry<String, String> entry = iter.next();
String url = entry.getKey();
if(urlMatcher.pathMatchesUrl(url, requestURI)) {
grantedAuthorities = entry.getValue();
break;
}
}
if(grantedAuthorities != null) {
ConfigAttributeEditor configAttrEditor = new ConfigAttributeEditor();
configAttrEditor.setAsText(grantedAuthorities);
return (ConfigAttributeDefinition) configAttrEditor.getValue();
}
return null;
}
/* (non-Javadoc)
* @see org.springframework.security.intercept.ObjectDefinitionSource#getConfigAttributeDefinitions()
*/
@SuppressWarnings("unchecked")
public Collection getConfigAttributeDefinitions() {
return null;
}
/* (non-Javadoc)
* @see org.springframework.security.intercept.ObjectDefinitionSource#supports(java.lang.Class)
*/
@SuppressWarnings("unchecked")
public boolean supports(Class clazz) {
return true;
}
/**
*
* @param filterInvocation
* @return
*/
@SuppressWarnings("unchecked")
private Map<String, String> getUrlAuthorities(FilterInvocation filterInvocation) {
ServletContext servletContext = filterInvocation.getHttpRequest().getSession().getServletContext();
return (Map<String, String>)servletContext.getAttribute("urlAuthorities");
}
}
4. 配置文件修改
接下来，我们来修改一下Spring Security的配置文件，把我们自定义的这个过滤器插入到过滤器链中去。
Xml代码
1. <beans:beans xmlns="http://www.springframework.org/schema/security"
2. xmlns:beans="http://www.springframework.org/schema/beans"
3. xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
4. xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
5. http://www.springframework.org/schema/security http://www.springframework.org/schema/security/spring-security-2.0.4.xsd">
6.
7. <beans:bean id="loggerListener" class="org.springframework.security.event.authentication.LoggerListener" />
8.
9. <http access-denied-page="/403.jsp" >
10. <intercept-url pattern="/static/**" filters="none" />
11. <intercept-url pattern="/template/**" filters="none" />
12. <intercept-url pattern="/" filters="none" />
13. <intercept-url pattern="/login.jsp" filters="none" />
14. <form-login login-page="/login.jsp" authentication-failure-url="/login.jsp?error=true" default-target-url="/index" />
15. <logout logout-success-url="/login.jsp"/>
16. <http-basic />
17. </http>
18.
19. <authentication-manager alias="authenticationManager"/>
20.
21. <authentication-provider user-service-ref="securityManager">
22. <password-encoder hash="md5"/>
23. </authentication-provider>
24.
25. <beans:bean id="accessDecisionManager" class="org.springframework.security.vote.AffirmativeBased">
26. <beans:property name="allowIfAllAbstainDecisions" value="false"/>
27. <beans:property name="decisionVoters">
28. <beans:list>
29. <beans:bean class="org.springframework.security.vote.RoleVoter"/>
30. <beans:bean class="org.springframework.security.vote.AuthenticatedVoter"/>
31. </beans:list>
32. </beans:property>
33. </beans:bean>
34.
35. <beans:bean id="resourceSecurityInterceptor" class="org.springframework.security.intercept.web.FilterSecurityInterceptor">
36. <beans:property name="authenticationManager" ref="authenticationManager"/>
37. <beans:property name="accessDecisionManager" ref="accessDecisionManager"/>
38. <beans:property name="objectDefinitionSource" ref="secureResourceFilterInvocationDefinitionSource" />
39. <beans:property name="observeOncePerRequest" value="false" />
40. <custom-filter after="LAST" />
41. </beans:bean>
42.
43. <beans:bean id="secureResourceFilterInvocationDefinitionSource" class="com.javaeye.sample.security.interceptor.SecureResourceFilterInvocationDefinitionSource" />
44.
45. </beans:beans>
<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-2.5.xsd
http://www.springframework.org/schema/security http://www.springframework.org/schema/security/spring-security-2.0.4.xsd">
<beans:bean id="loggerListener" class="org.springframework.security.event.authentication.LoggerListener" />
<http access-denied-page="/403.jsp" >
<intercept-url pattern="/static/**" filters="none" />
<intercept-url pattern="/template/**" filters="none" />
<intercept-url pattern="/" filters="none" />
<intercept-url pattern="/login.jsp" filters="none" />
<form-login login-page="/login.jsp" authentication-failure-url="/login.jsp?error=true" default-target-url="/index" />
<logout logout-success-url="/login.jsp"/>
<http-basic />
</http>
<authentication-manager alias="authenticationManager"/>
<authentication-provider user-service-ref="securityManager">
<password-encoder hash="md5"/>
</authentication-provider>
<beans:bean id="accessDecisionManager" class="org.springframework.security.vote.AffirmativeBased">
<beans:property name="allowIfAllAbstainDecisions" value="false"/>
<beans:property name="decisionVoters">
<beans:list>
<beans:bean class="org.springframework.security.vote.RoleVoter"/>
<beans:bean class="org.springframework.security.vote.AuthenticatedVoter"/>
</beans:list>
</beans:property>
</beans:bean>
<beans:bean id="resourceSecurityInterceptor" class="org.springframework.security.intercept.web.FilterSecurityInterceptor">
<beans:property name="authenticationManager" ref="authenticationManager"/>
<beans:property name="accessDecisionManager" ref="accessDecisionManager"/>
<beans:property name="objectDefinitionSource" ref="secureResourceFilterInvocationDefinitionSource" />
<beans:property name="observeOncePerRequest" value="false" />
<custom-filter after="LAST" />
</beans:bean>
<beans:bean id="secureResourceFilterInvocationDefinitionSource" class="com.javaeye.sample.security.interceptor.SecureResourceFilterInvocationDefinitionSource" />
</beans:beans>
请注意，由于我们所实现的，是FilterSecurityInterceptor中的一个开放接口，所以我们实际上定义了一个新的bean，并通过<custom-filter after="LAST" />插入到过滤器链中去。
Spring Security对象的访问
1. 访问当前登录用户
Spring Security提供了一个线程安全的对象：SecurityContextHolder，通过这个对象，我们可以访问当前的登录用户。我写了一个类，可以通过静态方法去读取：
Java代码
1. public class SecurityUserHolder {
2.
3. /**
4. * Returns the current user
5. *
6. * @return
7. */
8. public static User getCurrentUser() {
9. return (User) SecurityContextHolder.getContext().getAuthentication().getPrincipal();
10. }
11.
12. }
public class SecurityUserHolder {
/**
* Returns the current user
*
* @return
*/
public static User getCurrentUser() {
return (User) SecurityContextHolder.getContext().getAuthentication().getPrincipal();
}
}
2. 访问当前登录用户所拥有的权限
通过上面的分析，我们知道，用户所拥有的所有权限，其实是通过UserDetails接口中的getAuthorities()方法获得的。只要实现这个接口，就能实现需求。在我的代码中，不仅实现了这个接口，还在上面做了点小文章，这样我们可以获得一个用户所拥有权限的字符串表示：
Java代码
1. /* (non-Javadoc)
2. * @see org.springframework.security.userdetails.UserDetails#getAuthorities()
3. */
4. public GrantedAuthority[] getAuthorities() {
5. List<GrantedAuthority> grantedAuthorities = new ArrayList<GrantedAuthority>(roles.size());
6. for(Role role : roles) {
7. grantedAuthorities.add(new GrantedAuthorityImpl(role.getName()));
8. }
9. return grantedAuthorities.toArray(new GrantedAuthority[roles.size()]);
10. }
11.
12. /**
13. * Returns the authorites string
14. *
15. * eg.
16. * downpour --- ROLE_ADMIN,ROLE_USER
17. * robbin --- ROLE_ADMIN
18. *
19. * @return
20. */
21. public String getAuthoritiesString() {
22. List<String> authorities = new ArrayList<String>();
23. for(GrantedAuthority authority : this.getAuthorities()) {
24. authorities.add(authority.getAuthority());
25. }
26. return StringUtils.join(authorities, ",");
27. }
/* (non-Javadoc)
* @see org.springframework.security.userdetails.UserDetails#getAuthorities()
*/
public GrantedAuthority[] getAuthorities() {
List<GrantedAuthority> grantedAuthorities = new ArrayList<GrantedAuthority>(roles.size());
for(Role role : roles) {
grantedAuthorities.add(new GrantedAuthorityImpl(role.getName()));
}
return grantedAuthorities.toArray(new GrantedAuthority[roles.size()]);
}
/**
* Returns the authorites string
*
* eg.
* downpour --- ROLE_ADMIN,ROLE_USER
* robbin --- ROLE_ADMIN
*
* @return
*/
public String getAuthoritiesString() {
List<String> authorities = new ArrayList<String>();
for(GrantedAuthority authority : this.getAuthorities()) {
authorities.add(authority.getAuthority());
}
return StringUtils.join(authorities, ",");
}
3. 访问当前登录用户能够访问的资源
这就涉及到用户（User），权限（Role）和资源（Resource）三者之间的对应关系。我同样在User对象中实现了一个方法：
Java代码
1. /**
2. * @return the roleResources
3. */
4. public Map<String, List<Resource>> getRoleResources() {
5. // init roleResources for the first time
6. if(this.roleResources == null) {
7. this.roleResources = new HashMap<String, List<Resource>>();
8.
9. for(Role role : this.roles) {
10. String roleName = role.getName();
11. Set<Resource> resources = role.getResources();
12. for(Resource resource : resources) {
13. String key = roleName + "_" + resource.getType();
14. if(!this.roleResources.containsKey(key)) {
15. this.roleResources.put(key, new ArrayList<Resource>());
16. }
17. this.roleResources.get(key).add(resource);
18. }
19. }
20.
21. }
22. return this.roleResources;
23. }
/**
* @return the roleResources
*/
public Map<String, List<Resource>> getRoleResources() {
// init roleResources for the first time
if(this.roleResources == null) {
this.roleResources = new HashMap<String, List<Resource>>();
for(Role role : this.roles) {
String roleName = role.getName();
Set<Resource> resources = role.getResources();
for(Resource resource : resources) {
String key = roleName + "_" + resource.getType();
if(!this.roleResources.containsKey(key)) {
this.roleResources.put(key, new ArrayList<Resource>());
}
this.roleResources.get(key).add(resource);
}
}
}
return this.roleResources;
}
这里，会在User对象中设置一个缓存机制，在第一次取的时候，通过遍历User所有的Role，获取相应的Resource信息。
代码示例
在附件中，我给出了一个简单的例子，把我上面所讲到的所有内容整合在一起，是一个eclipse的工程，大家可以下载进行参考。