从Java应用程序连接LDAP服务器

Question

我正在构建一个基于GXT(J2EE)的应用程序.现在的问题是我必须将应用程序连接到LDAP服务器.您能告诉我如何从我们的Java应用程序连接LDAP服务器以及我将使用哪些库或API？

Answer 1

要连接到LDAP,请查看以下包/类:

javax.naming.directory.*
javax.naming.ladp.*
com.sun.jndi.ldap.LdapCtxFactory
com.sun.jndi.ldap.ControlFactory

示例代码:

//build a hashtable containing all the necessary configuration parameters
Hashtable<String, String> environment = new Hashtable<String, String>();

environment.put(LdapContext.CONTROL_FACTORIES, conf.getProperty("ldap.factories.control"));
environment.put(Context.INITIAL_CONTEXT_FACTORY, conf.getProperty("ldap.factories.initctx"));
environment.put(Context.PROVIDER_URL, conf.getProperty("ldap.host"));
environment.put(Context.SECURITY_AUTHENTICATION, "simple");
environment.put(Context.SECURITY_PRINCIPAL, conf.getProperty("ldap.user"));
environment.put(Context.SECURITY_CREDENTIALS, conf.getProperty("ldap.password"));
environment.put(Context.STATE_FACTORIES, "PersonStateFactory");
environment.put(Context.OBJECT_FACTORIES, "PersonObjectFactory");

// connect to LDAP
DirContext ctx = new InitialDirContext(environment);

// Specify the search filter
String FILTER = "(&(objectClass=Person) ((sAMAccountName=" + user.getUsername() + ")))";

// limit returned attributes to those we care about
String[] attrIDs = { "sn", "givenName" };

SearchControls ctls = new SearchControls();
ctls.setReturningAttributes(attrIDs);
ctls.setSearchScope(SearchControls.SUBTREE_SCOPE);

// Search for objects using filter and controls
NamingEnumeration answer = ctx.search(searchBase, FILTER, ctls);

...

SearchResult sr = (SearchResult) answer.next();
Attributes attrs = sr.getAttributes();
surName = attrs.get("sn").toString();
givenName = attrs.get("givenName").toString();
...

在这个例子中,我有一个Configuration对象,它从配置文件中读取这些值.

价值观将是:

# LDAP parameters
ldap.host = ldap://ldap.mydomain.com:389
ldap.factories.initctx = com.sun.jndi.ldap.LdapCtxFactory
ldap.factories.control = com.sun.jndi.ldap.ControlFactory
ldap.searchbase = dc=mydomain,dc=us
ldap.user = MYDOMAIN.COM\\ldap-user
ldap.userBase= MYDOMAIN.COM\\
ldap.password = ******

Answer 2

• 使用 Java 中的 JNDI（Java 命名和目录接口）API 连接到 LDAP 服务器。

• JNDI 的接口、类和异常在 JDK 附带的以下包中可用：

  • javax.naming.*
  • javax.naming.directory.*

• 这意味着在大多数情况下，我们不必使用任何外部库来处理 LDAP 服务器。

• 指定 LDAP 服务器的 URL 由主机名组成，LDAP 服务器在其上运行端口号。一个众所周知的轻量目录访问协议的端口号是 389，这是默认的。

• 还需要在 Hashtable 对象中为连接和身份验证指定一些环境属性。

这是示例代码：

import javax.naming.*;
import javax.naming.ldap.*;
import javax.naming.directory.*;

public class Ldap
{
    public static void main(String[]args)
    {
        Hashtable<String, String> environment = new Hashtable<String, String>();

        environment.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.ldap.LdapCtxFactory");
        environment.put(Context.PROVIDER_URL, "ldap://<hostname>:389");
        environment.put(Context.SECURITY_AUTHENTICATION, "simple");
        environment.put(Context.SECURITY_PRINCIPAL, "<Login DN>");
        environment.put(Context.SECURITY_CREDENTIALS, "<password>");

        try 
        {
            DirContext context = new InitialDirContext(environment);
            System.out.println("Connected..");
            System.out.println(context.getEnvironment());
            context.close();
        } 
        catch (AuthenticationNotSupportedException exception) 
        {
            System.out.println("The authentication is not supported by the server");
        }

        catch (AuthenticationException exception)
        {
            System.out.println("Incorrect password or username");
        }

        catch (NamingException exception)
        {
            System.out.println("Error when trying to create the context");
        }
    }
}