val buffer = Buffer()
        try {
          sink.use {
            source.use {
              while (true) {
                val byteCount = source.read(buffer, 8192L)
                if (byteCount == -1L) break
                sink.write(buffer, byteCount)
                sink.emit()
              }
            }
          }
        } catch (e: IOException) {
          logger.log(Level.WARNING, "$name failed", e)

    val isRunning: Boolean
    this.withLock {
      val i = readyAsyncCalls.iterator()
      while (i.hasNext()) {
        val asyncCall = i.next()

        if (runningAsyncCalls.size >= this.maxRequests) break // Max capacity.
        if (asyncCall.callsPerHost.get() >= this.maxRequestsPerHost) continue // Host max capacity.

        i.remove()
        asyncCall.callsPerHost.incrementAndGet()

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      Object form, made available under the License, as indicated by a
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      Object form, made available under the License, as indicated by a
      copyright notice that is included in or attached to the work
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      "Derivative Works" shall mean any work, whether in Source or Object
      form, that is based on (or derived from) the Work and for which the
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      Object form, made available under the License, as indicated by a
      copyright notice that is included in or attached to the work
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      "Derivative Works" shall mean any work, whether in Source or Object
      form, that is based on (or derived from) the Work and for which the
      editorial revisions, annotations, elaborations, or other modifications

      Object form, made available under the License, as indicated by a
      copyright notice that is included in or attached to the work
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      form, that is based on (or derived from) the Work and for which the
      editorial revisions, annotations, elaborations, or other modifications

      Object form, made available under the License, as indicated by a
      copyright notice that is included in or attached to the work
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      "Derivative Works" shall mean any work, whether in Source or Object
      form, that is based on (or derived from) the Work and for which the
      editorial revisions, annotations, elaborations, or other modifications