import com.google.bitcoin.net.NioClientManager; //导入依赖的package包/类
protected void initPeerGroup() {
    if (clientType == ClientType.NIO_CLIENT_MANAGER)
        peerGroup = new PeerGroup(unitTestParams, blockChain, new NioClientManager());
    else
        peerGroup = new PeerGroup(unitTestParams, blockChain, new BlockingClientManager());
    peerGroup.setPingIntervalMsec(0);  // Disable the pings as they just get in the way of most tests.
}
 

import com.google.bitcoin.net.NioClientManager; //导入依赖的package包/类
/**
 * Creates a PeerGroup for the given network and chain. Blocks will be passed to the chain as they are broadcast
 * and downloaded. This is probably the constructor you want to use.
 */
public PeerGroup(NetworkParameters params, @Nullable AbstractBlockChain chain) {
    this(params, chain, new NioClientManager());
}