import javax.jmdns.impl.tasks.resolver.ServiceResolver; //导入依赖的package包/类
/**
 * Renew a service when the record become stale. If there is no service collector for the type this method does nothing.
 *
 * @param record
 *            DNS record
 */
public void renewServiceCollector(DNSRecord record)
{
    ServiceInfo info = record.getServiceInfo();
    if (_serviceCollectors.containsKey(info.getType().toLowerCase()))
    {
        // Create/start ServiceResolver
        new ServiceResolver(this, info.getType()).start(_timer);
    }
}
 

import javax.jmdns.impl.tasks.resolver.ServiceResolver; //导入依赖的package包/类
@Override
public void startServiceResolver(String type) {
    new ServiceResolver(_jmDNSImpl, type).start(_timer);
}
 

import javax.jmdns.impl.tasks.resolver.ServiceResolver; //导入依赖的package包/类
/**
 * {@inheritDoc}
 */
@Override
public void addServiceListener(String type, ServiceListener listener)
{
    ServiceListenerStatus status = new ServiceListenerStatus(listener);
    final String lotype = type.toLowerCase();
    List<ServiceListenerStatus> list = _serviceListeners.get(lotype);
    if (list == null)
    {
        if (_serviceListeners.putIfAbsent(lotype, new LinkedList<ServiceListenerStatus>()) == null)
        {
            if (_serviceCollectors.putIfAbsent(lotype, new ServiceCollector(lotype)) == null)
            {
                this.addServiceListener(lotype, _serviceCollectors.get(lotype));
            }
        }
        list = _serviceListeners.get(lotype);
    }
    if (list != null)
    {
        synchronized (list)
        {
            if (!list.contains(listener))
            {
                list.add(status);
            }
        }
    }
    // report cached service types
    final List<ServiceEvent> serviceEvents = new ArrayList<ServiceEvent>();
    Collection<DNSEntry> dnsEntryLits = this.getCache().allValues();
    for (DNSEntry entry : dnsEntryLits)
    {
        final DNSRecord record = (DNSRecord) entry;
        if (record.getRecordType() == DNSRecordType.TYPE_SRV)
        {
            if (record.getName().endsWith(type))
            {
                // Do not used the record embedded method for generating event this will not work.
                // serviceEvents.add(record.getServiceEvent(this));
                serviceEvents.add(new ServiceEventImpl(this, type, toUnqualifiedName(type, record.getName()), record.getServiceInfo()));
            }
        }
    }
    // Actually call listener with all service events added above
    for (ServiceEvent serviceEvent : serviceEvents)
    {
        status.serviceAdded(serviceEvent);
    }
    // Create/start ServiceResolver
    new ServiceResolver(this, type).start(_timer);
}