LdapContext,怎么做select count(*)

import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import javax.naming.directory.InitialDirContext;
import javax.naming.directory.SearchControls;
import javax.naming.directory.SearchResult;
import java.util.Hashtable;

public class LdapCountExample {
    public static void main(String[] args) {
        Hashtable<String, String> env = new Hashtable<>();
        env.put("java.naming.factory.initial", "com.sun.jndi.ldap.LdapCtxFactory");
        env.put("java.naming.provider.url", "ldap://localhost:389/dc=example,dc=com");
        env.put("java.naming.security.authentication", "simple");
        env.put("java.naming.security.principal", "cn=admin,dc=example,dc=com");
        env.put("java.naming.security.credentials", "password");

        try {
            InitialDirContext context = new InitialDirContext(env);

            SearchControls controls = new SearchControls();
            controls.setSearchScope(SearchControls.SUBTREE_SCOPE);
            controls.setCountLimit(Integer.MAX_VALUE);
            controls.setTimeLimit(Integer.MAX_VALUE);

            NamingEnumeration<SearchResult> results = context.search("", "(objectClass=*)", controls);

            int count = 0;
            while (results.hasMore()) {
                results.next();
                count++;
            }

            System.out.println("Count: " + count);

            context.close();
        } catch (NamingException e) {
            e.printStackTrace();
        }
    }
}