序
本文主要研究一下AsyncHttpClient的ClientStats
ClientStats
org/asynchttpclient/ClientStats.java
代码语言：javascript复制/**
* A record class representing the state of an (@link org.asynchttpclient.AsyncHttpClient).
*/
public class ClientStats {
private final Map<String, HostStats> statsPerHost;
public ClientStats(Map<String, HostStats> statsPerHost) {
this.statsPerHost = Collections.unmodifiableMap(statsPerHost);
}
/**
* @return A map from hostname to statistics on that host's connections.
* The returned map is unmodifiable.
*/
public Map<String, HostStats> getStatsPerHost() {
return statsPerHost;
}
/**
* @return The sum of {@link #getTotalActiveConnectionCount()} and {@link #getTotalIdleConnectionCount()},
* a long representing the total number of connections in the connection pool.
*/
public long getTotalConnectionCount() {
return statsPerHost
.values()
.stream()
.mapToLong(HostStats::getHostConnectionCount)
.sum();
}
/**
* @return A long representing the number of active connections in the connection pool.
*/
public long getTotalActiveConnectionCount() {
return statsPerHost
.values()
.stream()
.mapToLong(HostStats::getHostActiveConnectionCount)
.sum();
}
/**
* @return A long representing the number of idle connections in the connection pool.
*/
public long getTotalIdleConnectionCount() {
return statsPerHost
.values()
.stream()
.mapToLong(HostStats::getHostIdleConnectionCount)
.sum();
}
@Override
public String toString() {
return "There are " getTotalConnectionCount()
" total connections, " getTotalActiveConnectionCount()
" are active and " getTotalIdleConnectionCount() " are idle.";
}
@Override
public boolean equals(final Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
final ClientStats that = (ClientStats) o;
return Objects.equals(statsPerHost, that.statsPerHost);
}
@Override
public int hashCode() {
return Objects.hashCode(statsPerHost);
}
}
ClientStats通过
Map<String, HostStats>维护了每个host对应的统计；它提供了getStatsPerHost、getTotalConnectionCount、getTotalActiveConnectionCount、getTotalIdleConnectionCount方法
HostStats
org/asynchttpclient/HostStats.java
代码语言：javascript复制/**
* A record class representing the status of connections to some host.
*/
public class HostStats {
private final long activeConnectionCount;
private final long idleConnectionCount;
public HostStats(long activeConnectionCount,
long idleConnectionCount) {
this.activeConnectionCount = activeConnectionCount;
this.idleConnectionCount = idleConnectionCount;
}
/**
* @return The sum of {@link #getHostActiveConnectionCount()} and {@link #getHostIdleConnectionCount()},
* a long representing the total number of connections to this host.
*/
public long getHostConnectionCount() {
return activeConnectionCount idleConnectionCount;
}
/**
* @return A long representing the number of active connections to the host.
*/
public long getHostActiveConnectionCount() {
return activeConnectionCount;
}
/**
* @return A long representing the number of idle connections in the connection pool.
*/
public long getHostIdleConnectionCount() {
return idleConnectionCount;
}
@Override
public String toString() {
return "There are " getHostConnectionCount()
" total connections, " getHostActiveConnectionCount()
" are active and " getHostIdleConnectionCount() " are idle.";
}
@Override
public boolean equals(final Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
final HostStats hostStats = (HostStats) o;
return activeConnectionCount == hostStats.activeConnectionCount &&
idleConnectionCount == hostStats.idleConnectionCount;
}
@Override
public int hashCode() {
return Objects.hash(activeConnectionCount, idleConnectionCount);
}
}
HostStats定义了activeConnectionCount、idleConnectionCount属性
getClientStats
org/asynchttpclient/netty/channel/ChannelManager.java
代码语言：javascript复制 public ClientStats getClientStats() {
Map<String, Long> totalConnectionsPerHost = openChannels.stream().map(Channel::remoteAddress).filter(a -> a.getClass() == InetSocketAddress.class)
.map(a -> (InetSocketAddress) a).map(InetSocketAddress::getHostName).collect(Collectors.groupingBy(Function.identity(), Collectors.counting()));
Map<String, Long> idleConnectionsPerHost = channelPool.getIdleChannelCountPerHost();
Map<String, HostStats> statsPerHost = totalConnectionsPerHost.entrySet().stream().collect(Collectors.toMap(Entry::getKey, entry -> {
final long totalConnectionCount = entry.getValue();
final long idleConnectionCount = idleConnectionsPerHost.getOrDefault(entry.getKey(), 0L);
final long activeConnectionCount = totalConnectionCount - idleConnectionCount;
return new HostStats(activeConnectionCount, idleConnectionCount);
}));
return new ClientStats(statsPerHost);
}
ChannelManager提供了getClientStats方法，它从openChannels获取totalConnectionsPerHost，从channelPool.getIdleChannelCountPerHost()获取idleConnectionCount，然后创建HostStats，最后返回ClientStats
小结
AsyncHttpClient提供了ClientStats用于获取连接的统计信息，可按host维度，统计activeConnectionCount、idleConnectionCount，也可汇总查看totalConnectionCount、totalActiveConnectionCount、totalIdleConnectionCount。它可以从ChannelManager获取。对于使用micrometer的可以使用这个作为数据源进行适配。
