如何在spring LDAP中解决ldap套接字关闭错误？

import org.springframework.ldap.core.support.LdapContextSource;

public class LdapConfig {
    public LdapContextSource contextSource() {
        LdapContextSource contextSource = new LdapContextSource();
        contextSource.setUrl("ldap://ldap.example.com:389");
        contextSource.setBase("dc=example,dc=com");
        contextSource.setUserDn("cn=admin,dc=example,dc=com");
        contextSource.setPassword("password");
        contextSource.setPooled(true); // 开启连接池
        contextSource.setConnectTimeout(5000); // 设置连接超时时间为5秒
        return contextSource;
    }
}