如何获得最大Java动态地显示Active Directory的页面大小

问题描述

当该组的成员超过1500个时，我的ldap连接出现问题。我可以使用以下代码段解决它。虽然这项工作有效，但我对硬编码的PAGESIZE变量非常不满意。由于这是AD服务器上的设置，因此我不知道它是否以及何时会更改。所以我的问题是，是否可以使用javax-library或任何其他库动态地获取此pagesize值？ 如果有人知道解决此问题的完全不同的方法，我也很好奇。我认为，在generaterangeString(int i)函数中生成此成员字符串必须有更好的方法。

package main.java;

import javax.naming.Context;
import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import javax.naming.directory.SearchControls;
import javax.naming.directory.SearchResult;
import javax.naming.ldap.InitialLdapContext;
import javax.naming.ldap.LdapContext;
import java.util.Properties;

public class LdapService {

    private static final int PAGESIZE = 1500;

    public void printAllMembersOfSpecificGroup() throws Exception {
        // Initialize
        LdapContext ldapContext = null;
        NamingEnumeration<SearchResult> results = null;
        NamingEnumeration<?> members = null;

        try {

            Properties properties = new Properties();
            properties.put(Context.INITIAL_CONTEXT_FACTORY,"com.sun.jndi.ldap.LdapCtxFactory");
            properties.put(Context.PROVIDER_URL,"ldap://url");
            properties.put(Context.Security_AUTHENTICATION,"simple");
            properties.put(Context.Security_PRINCIPAL,"Security Principle");
            properties.put(Context.Security_CREDENTIALS,"password");


            ldapContext = new InitialLdapContext(properties,null);

            int range = 0;
            boolean finish = false;
            while (finish != true) {
                // Set search controls
                SearchControls searchCtls = new SearchControls();
                searchCtls.setSearchScope(SearchControls.SUBTREE_ScopE);
                searchCtls.setReturningAttributes(generaterangeArray(range));

                // Get results
                results = ldapContext.search("base string",String.format("(CN=%s)","Group name"),searchCtls);
                if (results.hasMoreElements() == true) {
                    SearchResult result = results.next();
                    try {
                        if(result.getAttributes().get(generaterangeString(range)) == null){
                            members = result.getAttributes().get(generateLastRangeString(range)).getAll();
                        } else {
                            members = result.getAttributes().get(generaterangeString(range)).getAll();
                        }
                        while (members.hasMore()) {
                            String distinguishedname = (String) members.next();
                            System.out.println(distinguishedname);
                        }
                        range++;
                    } catch (Exception e) {
                        // Fails means there is no more result
                        e.printstacktrace();
                        finish = true;
                    }
                }
            }
        } catch (NamingException e) {
            throw new Exception(e.getMessage());
        } finally {
            if (ldapContext != null) {
                ldapContext.close();
            }
            if (results != null) {
                results.close();
            }
        }
    }

    public static String[] generaterangeArray(int i) {
        String range = "member;range=" + i * PAGESIZE + "-" + ((i + 1) * PAGESIZE - 1);
        String[] returnedAtts = { range };

        return returnedAtts;
    }

    public static String generaterangeString(int i) {
        String range = "member;range=" + i * PAGESIZE + "-" + ((i + 1) * PAGESIZE - 1);

        return range;
    }
    public static String generateLastRangeString(int i) {
        String range = "member;range=" + i * PAGESIZE + "-" + "*";

        return range;
    }
}

解决方法

如果仅使用默认查询策略，请在以下位置搜索 CN =默认查询策略，CN =查询策略，CN =目录服务，CN = Windows NT，CN =服务，CN =配置，域命名上下文（例如 CN =默认查询策略，CN =查询策略，CN =目录服务，CN = Windows NT，CN =服务，CN =配置，DC =示例，DC = com），过滤器如“（＆（cn = *） ）“

返回ldapAdminLimits。从属性中解析出MaxPageSize：

lDAPAdminLimits（13）：MaxValRange = 1500; MaxReceiveBuffer = 10485760; MaxDatagramRecv = 4096; MaxPoolThreads = 4; MaxResultSetSize = 262144; MaxTempTableSize = 10000; MaxQueryDuration = 120; MaxPageSize = 1000 ； MaxNotificationPerConn = 5; MaxActiveQueries = 20; MaxConnIdleTime = 900; InitRecvTimeout = 120; MaxConnections = 5000;

要查找所有查询策略，请在CN = Query-Policies，CN = Directory Service，CN = Windows NT，CN = Services，CN = Configuration，域命名上下文中进行搜索（＆ （objectClass = queryPolicy））...或者对查询策略进行大量研究，弄清楚如何确定哪个适用于您的连接，或者采用最低的值并知道您的安全性。