CommSystemFacadeImpl (Javadocs [I2P+ 2.11.0+]

java.lang.Object
- net.i2p.router.CommSystemFacade
- - net.i2p.router.transport.CommSystemFacadeImpl

All Implemented Interfaces:

Service
```
public class CommSystemFacadeImpl
extends CommSystemFacade
```
Primary implementation of the communication system facade for I2P network operations. This class provides the main interface between the router core and all transport protocols. It coordinates message sending, peer management, address configuration, and network monitoring while abstracting the underlying transport details. Core Responsibilities:
- Message routing and delivery across all transports
- Peer connection management and statistics
- Network address discovery and configuration
- Bandwidth allocation and monitoring
- Transport lifecycle management (start/stop/restart)
- Network reachability testing and reporting
- Geographic IP filtering and country blocking
- Communication system status and health monitoring
Transport Integration:
- Manages NTCP, UDP, and SSU transports
- Handles transport selection and failover
- Coordinates address updates across protocols
- Provides unified API for router components
Configuration Features:
- Transport enable/disable controls
- Country-based blocking and filtering
- Proxy configuration and detection
- Network monitoring and testing options
- IPv4 and IPv6 addressing support
Security Features:
- Geographic IP filtering
- Country-based access controls
- Peer reputation and banlist management
- Transport-specific security policies

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class CommSystemFacadeImpl.CacheEntry
Cache entry for IP address and hostname mappings.
- Nested classes/interfaces inherited from class net.i2p.router.CommSystemFacade
  CommSystemFacade.Status

Nested Classes
Modifier and Type	Class and Description
`static class`	`CommSystemFacadeImpl.CacheEntry` Cache entry for IP address and hostname mappings.

Field Summary

Fields
Modifier and Type Field and Description

static String PROP_BLOCK_MY_COUNTRY

static String PROP_IP_COUNTRY
- Fields inherited from class net.i2p.router.CommSystemFacade
  ROUTER_BUNDLE_NAME, STATUS_DIFFERENT, STATUS_DISCONNECTED, STATUS_HOSED, STATUS_IPV4_DISABLED_IPV6_FIREWALLED, STATUS_IPV4_DISABLED_IPV6_OK, STATUS_IPV4_DISABLED_IPV6_UNKNOWN, STATUS_IPV4_FIREWALLED_IPV6_OK, STATUS_IPV4_FIREWALLED_IPV6_UNKNOWN, STATUS_IPV4_OK_IPV6_FIREWALLED, STATUS_IPV4_OK_IPV6_UNKNOWN, STATUS_IPV4_SNAT_IPV6_OK, STATUS_IPV4_SNAT_IPV6_UNKNOWN, STATUS_IPV4_UNKNOWN_IPV6_FIREWALLED, STATUS_IPV4_UNKNOWN_IPV6_OK, STATUS_OK, STATUS_REJECT_UNSOLICITED, STATUS_UNKNOWN

Fields
Modifier and Type	Field and Description
`static String`	`PROP_BLOCK_MY_COUNTRY`
`static String`	`PROP_IP_COUNTRY`

Constructor Summary

Constructors
Constructor and Description

CommSystemFacadeImpl(RouterContext context)

Constructors
Constructor and Description
`CommSystemFacadeImpl(RouterContext context)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`int`	`countActivePeers()` How many peers are we currently connected to, that we have sent a message to or received a message from in the last minute.
`int`	`countActiveSendPeers()` How many peers are we currently connected to, that we have sent a message to in the last minute.
`static int`	`countRdnsCacheEntries()`
`List<RouterAddress>`	`createAddresses()` Create router addresses for all configured transport protocols.
`boolean`	`enableReverseLookups()`
`boolean`	`enableWhoisLookups()`
`void`	`exemptIncoming(Hash peer)` Exempt this router hash from any incoming throttles or rejections
`void`	`forceDisconnect(Hash peer)` Tell the comm system to disconnect from this peer.
`String`	`getCanonicalHostName(String ipAddress)` Returns the canonical hostname for the given IP address from cache or DNS.
`String`	`getCanonicalHostNameSync(String ipAddress)`
`static byte[]`	`getCompatibleIP(RouterInfo ri)` Return the first IP compatible with our outbound transports.
`Map<String,String>`	`getCountries()` Provides country code mappings.
`String`	`getCountry(Hash peer)` Uses the transport IP first because that lookup is fast, then the IP from the netDb.
`String`	`getCountry(String ip)` Get country code for an IP address.
`String`	`getCountryName(String c)` full name for a country code, or the code if we don't know the name
`static String`	`getDomain(String hostname)`
`List<Hash>`	`getEstablished()` Get all the peers we are connected to.
`long`	`getFramedAveragePeerClockSkew(int percentToInclude)` Return framed average clock skew of connected peers in seconds, or null if we cannot answer.
`byte[]`	`getIP(Hash peer)`
`String`	`getLocalizedStatusString()` getStatus().toStatusString(), translated if available.
`List<String>`	`getMostRecentErrorMessages()`
`String`	`getOurCountry()`
`static String`	`getRdnsCacheStats()` Get cache statistics for monitoring
`CommSystemFacade.Status`	`getStatus()` Determine under what conditions we are remotely reachable.
`SortedMap<String,Transport>`	`getTransports()`
`static byte[]`	`getValidIP(RouterInfo ri)` Return first valid IP (v4 or v6) we find, any transport.
`X25519KeyFactory`	`getXDHFactory()` Factory for making X25519 key pairs.
`boolean`	`haveHighOutboundCapacity()`
`boolean`	`haveInboundCapacity(int pct)`
`boolean`	`haveOutboundCapacity(int pct)`
`void`	`initGeoIP()` Router must call after netdb is initialized
`boolean`	`isBacklogged(Hash peer)`
`boolean`	`isDummy()` Is everything disabled for testing?
`boolean`	`isEstablished(Hash peer)`
`boolean`	`isExemptIncoming(String ip)` Is this IP exempt from any incoming throttles or rejections
`boolean`	`isInStrictCountry()` Are we in a strict country
`boolean`	`isInStrictCountry(Hash peer)` Are they in a strict country.
`boolean`	`isInStrictCountry(RouterInfo ri)` Are they in a strict country
`boolean`	`isRunning()`
`void`	`mayDisconnect(Hash peer)` Tell the comm system that we may disconnect from this peer.
`void`	`notifyRemoveAddress(boolean ipv6)` Tell other transports our address changed
`void`	`notifyRemoveAddress(RouterAddress address)` Tell other transports our address changed
`void`	`notifyReplaceAddress(RouterAddress udpAddr)` UDP changed addresses, tell NTCP and restart All the work moved to NTCPTransport.externalAddressReceived()
`void`	`processMessage(OutNetMessage msg)` Process and route an outbound message through the transport system.
`void`	`queueLookup(byte[] ip)`
`static String`	`rdnsCacheSize()`
`void`	`registerTransport(Transport t)` Pluggable transports.
`void`	`removeExemption(String ip)` Remove this IP from the exemptions
`String`	`renderPeerCaps(Hash peer, boolean inline)` Renders the peer's capability HTML block.
`String`	`renderPeerFlag(Hash peer)`
`String`	`renderPeerHTML(Hash peer, boolean extended)` Renders HTML for a peer with optional extended info.
`void`	`renderStatusHTML(Writer out, String urlBase, int sortFlags)` As of 0.9.31, only outputs UPnP status Warning - blocking, very slow, queries the active UPnP router, will take many seconds if it has vanished.
`void`	`restart()` Restart the communication system.
`void`	`shutdown()` Gracefully shutdown the communication system.
`void`	`startup()` Start the communication system and all transport protocols.
`void`	`unregisterTransport(Transport t)` Pluggable transports.
`boolean`	`wasUnreachable(Hash peer)`

Methods inherited from class net.i2p.router.CommSystemFacade
getMedianPeerClockSkew, renderStatusHTML

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - PROP_BLOCK_MY_COUNTRY
```
public static final String PROP_BLOCK_MY_COUNTRY
```
    See Also:
    
    Constant Field Values
  - PROP_IP_COUNTRY
```
public static final String PROP_IP_COUNTRY
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - CommSystemFacadeImpl
```
public CommSystemFacadeImpl(RouterContext context)
```
- Method Detail
  - countActivePeers
```
public int countActivePeers()
```
    How many peers are we currently connected to, that we have sent a message to or received a message from in the last minute.
    
    Specified by:
    
    countActivePeers in class CommSystemFacade
  - countActiveSendPeers
```
public int countActiveSendPeers()
```
    How many peers are we currently connected to, that we have sent a message to in the last minute. Unused for anything, to be removed.
    
    Specified by:
    
    countActiveSendPeers in class CommSystemFacade
  - countRdnsCacheEntries
```
public static int countRdnsCacheEntries()
```
  - createAddresses
```
public List<RouterAddress> createAddresses()
```
    Create router addresses for all configured transport protocols. This method generates RouterAddress objects for each transport protocol based on current configuration and network conditions. It handles address discovery, validation, and format conversion. Address Creation:
    - Iterates through all registered transports
    - Gets current addresses from each transport
    - Validates address format and consistency
    - Handles IPv4 and IPv6 address generation
    - Applies geographic and network filtering
    Overrides:
    
    createAddresses in class CommSystemFacade
    
    Returns:
    
    list of RouterAddress objects for all active transports, may be empty if no addresses available
  - enableReverseLookups
```
public boolean enableReverseLookups()
```
  - enableWhoisLookups
```
public boolean enableWhoisLookups()
```
  - exemptIncoming
```
public void exemptIncoming(Hash peer)
```
    Exempt this router hash from any incoming throttles or rejections
    
    Overrides:
    
    exemptIncoming in class CommSystemFacade
  - forceDisconnect
```
public void forceDisconnect(Hash peer)
```
    Tell the comm system to disconnect from this peer.
    
    Overrides:
    
    forceDisconnect in class CommSystemFacade
  - getCanonicalHostName
```
public String getCanonicalHostName(String ipAddress)
```
    Returns the canonical hostname for the given IP address from cache or DNS. Falls back to a WHOIS lookup if DNS fails, returning "ip (whois info)" if available, or just the IP if WHOIS data is missing.
    
    Overrides:
    
    getCanonicalHostName in class CommSystemFacade
    
    Parameters:
    
    ipAddress - IP address to resolve, or null/"null" to return null
    
    Returns:
    
    hostname, IP with WHOIS info, just IP if no WHOIS, or null for invalid input
  - getCanonicalHostNameSync
```
public String getCanonicalHostNameSync(String ipAddress)
```
    Overrides:
    
    getCanonicalHostNameSync in class CommSystemFacade
  - getCompatibleIP
```
public static byte[] getCompatibleIP(RouterInfo ri)
```
    Return the first IP compatible with our outbound transports. If the peer has both IPv4 and IPv6 addresses, and we support both, prefer IPv4. If we only support one, return only that type. Falls back to any valid IP if no compatible one found.
    
    Returns:
    
    IP or null
  - getCountries
```
public Map<String,String> getCountries()
```
    Provides country code mappings.
    
    Overrides:
    
    getCountries in class CommSystemFacade
    
    Returns:
    
    Unmodifiable map of lower-case country codes to untranslated names. Returns empty map if geoIP data is unavailable.
  - getCountry
```
public String getCountry(Hash peer)
```
    Uses the transport IP first because that lookup is fast, then the IP from the netDb. Not recommended for our local router hash, as we may not be either in the cache or netdb, or may not be publishing an IP. As of 0.9.32, works only for literal IPs, returns null for hostnames.
    
    Overrides:
    
    getCountry in class CommSystemFacade
    
    Parameters:
    
    peer - not ourselves - use getOurCountry() for that
    
    Returns:
    
    two-letter lower-case country code or xx for non-banned peers, or null otherwise
  - getCountry
```
public String getCountry(String ip)
```
    Get country code for an IP address.
    
    Overrides:
    
    getCountry in class CommSystemFacade
    
    Parameters:
    
    ip - IP address string (IPv4 or IPv6)
    
    Returns:
    
    two-letter lower-case country code or null if not found
  - getCountryName
```
public String getCountryName(String c)
```
    full name for a country code, or the code if we don't know the name
    
    Overrides:
    
    getCountryName in class CommSystemFacade
  - getDomain
```
public static String getDomain(String hostname)
```
    Returns:
    
    domain name only from reverse dns hostname lookups
  - getEstablished
```
public List<Hash> getEstablished()
```
    Description copied from class: CommSystemFacade
    
    Get all the peers we are connected to. This should be more efficient than repeated calls to isEstablished() if you have to check a lot.
    
    Specified by:
    
    getEstablished in class CommSystemFacade
    
    Returns:
    
    a new list, may be modified
  - getFramedAveragePeerClockSkew
```
public long getFramedAveragePeerClockSkew(int percentToInclude)
```
    Description copied from class: CommSystemFacade
    
    Return framed average clock skew of connected peers in seconds, or null if we cannot answer. CommSystemFacadeImpl overrides this.
    
    Overrides:
    
    getFramedAveragePeerClockSkew in class CommSystemFacade
    
    Parameters:
    
    percentToInclude - 1-100
    
    Returns:
    
    Framed average clock skew of connected peers in milliseconds, or the clock offset if we cannot answer. Average is calculated over the middle "percentToInclude" peers. A positive number means our clock is ahead of theirs. Todo: change List to milliseconds
  - getIP
```
public byte[] getIP(Hash peer)
```
    Overrides:
    
    getIP in class CommSystemFacade
  - getLocalizedStatusString
```
public String getLocalizedStatusString()
```
    getStatus().toStatusString(), translated if available.
    
    Overrides:
    
    getLocalizedStatusString in class CommSystemFacade
  - getMostRecentErrorMessages
```
public List<String> getMostRecentErrorMessages()
```
    Overrides:
    
    getMostRecentErrorMessages in class CommSystemFacade
  - getOurCountry
```
public String getOurCountry()
```
    Overrides:
    
    getOurCountry in class CommSystemFacade
    
    Returns:
    
    two-letter lower-case country code or null
  - getRdnsCacheStats
```
public static String getRdnsCacheStats()
```
    Get cache statistics for monitoring
    
    Returns:
    
    formatted string with cache stats
  - getStatus
```
public CommSystemFacade.Status getStatus()
```
    Description copied from class: CommSystemFacade
    
    Determine under what conditions we are remotely reachable.
    
    Overrides:
    
    getStatus in class CommSystemFacade
  - getTransports
```
public SortedMap<String,Transport> getTransports()
```
    Overrides:
    
    getTransports in class CommSystemFacade
    
    Returns:
    
    SortedMap of style to Transport (a copy)
  - getValidIP
```
public static byte[] getValidIP(RouterInfo ri)
```
    Return first valid IP (v4 or v6) we find, any transport. Local and other invalid IPs will not be returned. As of 0.9.32, works only for literal IPs, returns null for host names.
    
    Returns:
    
    IP or null
  - getXDHFactory
```
public X25519KeyFactory getXDHFactory()
```
    Factory for making X25519 key pairs.
    
    Overrides:
    
    getXDHFactory in class CommSystemFacade
  - haveHighOutboundCapacity
```
public boolean haveHighOutboundCapacity()
```
    Overrides:
    
    haveHighOutboundCapacity in class CommSystemFacade
  - haveInboundCapacity
```
public boolean haveInboundCapacity(int pct)
```
    Overrides:
    
    haveInboundCapacity in class CommSystemFacade
  - haveOutboundCapacity
```
public boolean haveOutboundCapacity(int pct)
```
    Overrides:
    
    haveOutboundCapacity in class CommSystemFacade
  - initGeoIP
```
public void initGeoIP()
```
    Router must call after netdb is initialized
    
    Overrides:
    
    initGeoIP in class CommSystemFacade
  - isBacklogged
```
public boolean isBacklogged(Hash peer)
```
    Overrides:
    
    isBacklogged in class CommSystemFacade
  - isDummy
```
public boolean isDummy()
```
    Is everything disabled for testing?
    
    Overrides:
    
    isDummy in class CommSystemFacade
  - isEstablished
```
public boolean isEstablished(Hash peer)
```
    Specified by:
    
    isEstablished in class CommSystemFacade
  - isExemptIncoming
```
public boolean isExemptIncoming(String ip)
```
    Is this IP exempt from any incoming throttles or rejections
    
    Overrides:
    
    isExemptIncoming in class CommSystemFacade
    
    Parameters:
    
    ip - canonical string
  - isInStrictCountry
```
public boolean isInStrictCountry()
```
    Are we in a strict country
    
    Overrides:
    
    isInStrictCountry in class CommSystemFacade
  - isInStrictCountry
```
public boolean isInStrictCountry(Hash peer)
```
    Are they in a strict country. Not recommended for our local router hash, as we may not be either in the cache or netdb, or may not be publishing an IP.
    
    Overrides:
    
    isInStrictCountry in class CommSystemFacade
    
    Parameters:
    
    peer - non-null
  - isInStrictCountry
```
public boolean isInStrictCountry(RouterInfo ri)
```
    Are they in a strict country
    
    Overrides:
    
    isInStrictCountry in class CommSystemFacade
    
    Parameters:
    
    ri - non-null
  - isRunning
```
public boolean isRunning()
```
    Overrides:
    
    isRunning in class CommSystemFacade
  - mayDisconnect
```
public void mayDisconnect(Hash peer)
```
    Tell the comm system that we may disconnect from this peer. This is advisory only.
    
    Overrides:
    
    mayDisconnect in class CommSystemFacade
  - notifyRemoveAddress
```
public void notifyRemoveAddress(boolean ipv6)
```
    Tell other transports our address changed
    
    Overrides:
    
    notifyRemoveAddress in class CommSystemFacade
  - notifyRemoveAddress
```
public void notifyRemoveAddress(RouterAddress address)
```
    Tell other transports our address changed
    
    Overrides:
    
    notifyRemoveAddress in class CommSystemFacade
    
    Parameters:
    
    address - may be null; or address's host/IP may be null
  - notifyReplaceAddress
```
public void notifyReplaceAddress(RouterAddress udpAddr)
```
    UDP changed addresses, tell NTCP and restart All the work moved to NTCPTransport.externalAddressReceived()
    
    Overrides:
    
    notifyReplaceAddress in class CommSystemFacade
    
    Parameters:
    
    udpAddr - may be null; or udpAddr's host/IP may be null
  - processMessage
```
public void processMessage(OutNetMessage msg)
```
    Process and route an outbound message through the transport system. This method is the central entry point for sending messages to other I2P peers. It selects appropriate transport, handles message queuing, and manages delivery tracking. Message Processing:
    - Transport selection based on destination
    - Message validation and filtering
    - Queueing and throttling
    - Delivery status tracking
    - Failure handling and retry logic
    - Callback execution for send completion
    Specified by:
    
    processMessage in class CommSystemFacade
    
    Parameters:
    
    msg - the outbound message to be processed and delivered
  - queueLookup
```
public void queueLookup(byte[] ip)
```
    Overrides:
    
    queueLookup in class CommSystemFacade
    
    Parameters:
    
    ip - ipv4 or ipv6
  - rdnsCacheSize
```
public static String rdnsCacheSize()
```
  - registerTransport
```
public void registerTransport(Transport t)
```
    Pluggable transports. Not for NTCP or SSU. Do not call from transport constructor. Transport must be ready to be started. Following transport methods will be called: setListener() externalAddressReceived() (zero or more times, one for each known address) startListening();
    
    Overrides:
    
    registerTransport in class CommSystemFacade
  - removeExemption
```
public void removeExemption(String ip)
```
    Remove this IP from the exemptions
    
    Overrides:
    
    removeExemption in class CommSystemFacade
    
    Parameters:
    
    ip - canonical string
  - renderPeerCaps
```
public String renderPeerCaps(Hash peer,
                             boolean inline)
```
    Renders the peer's capability HTML block. Caches data and removes unnecessary repeated computation.
    
    Overrides:
    
    renderPeerCaps in class CommSystemFacade
    
    Parameters:
    
    peer - Peer Hash
    
    inline - If true, render inline without table wrapper
    
    Returns:
    
    HTML snippet of peer capabilities
  - renderPeerFlag
```
public String renderPeerFlag(Hash peer)
```
    Overrides:
    
    renderPeerFlag in class CommSystemFacade
  - renderPeerHTML
```
public String renderPeerHTML(Hash peer,
                             boolean extended)
```
    Renders HTML for a peer with optional extended info. Uses cached RouterInfo, country info, and reverse lookup cache.
    
    Overrides:
    
    renderPeerHTML in class CommSystemFacade
    
    Parameters:
    
    peer - Peer Hash
    
    extended - Whether to show extended capabilities
    
    Returns:
    
    HTML snippet representing peer
  - renderStatusHTML
```
public void renderStatusHTML(Writer out,
                             String urlBase,
                             int sortFlags)
                      throws IOException
```
    As of 0.9.31, only outputs UPnP status Warning - blocking, very slow, queries the active UPnP router, will take many seconds if it has vanished.
    
    Overrides:
    
    renderStatusHTML in class CommSystemFacade
    
    Throws:
    
    IOException
  - restart
```
public void restart()
```
    Restart the communication system. This method performs a complete restart of all transport protocols while preserving router state. It stops all transports, reinitializes system components, and restarts network operations. Restart Process:
    - Stop all transport protocols gracefully
    - Reinitialize system components
    - Restart transports with preserved state
    - Resume network operations and monitoring
    - Reconfigure address management
    Throws:
    
    IllegalStateException - if not running
  - shutdown
```
public void shutdown()
```
    Gracefully shutdown the communication system. This method performs a clean shutdown of all transport protocols and network operations. It stops accepting new connections, closes existing ones, and performs cleanup of system resources. Shutdown Process:
    - Stop network monitoring
    - Stop all transport protocols
    - Close all active connections
    - Cleanup system resources and caches
    - Save final state and statistics
    Throws:
    
    IllegalStateException - if not running
  - startup
```
public void startup()
```
    Start the communication system and all transport protocols. This method initializes the communication system, starts all configured transports, and begins network operations. It handles transport discovery, address configuration, and peer management setup. Startup Process:
    - Initialize geographic IP filtering
    - Start network monitoring
    - Register and start all configured transports
    - Begin peer discovery and connection attempts
    - Setup address change notifications
    Throws:
    
    IllegalStateException - if already running
  - unregisterTransport
```
public void unregisterTransport(Transport t)
```
    Pluggable transports. Not for NTCP or SSU. Following transport methods will be called: setListener(null) stoptListening();
    
    Overrides:
    
    unregisterTransport in class CommSystemFacade
  - wasUnreachable
```
public boolean wasUnreachable(Hash peer)
```
    Overrides:
    
    wasUnreachable in class CommSystemFacade

Class CommSystemFacadeImpl

Nested Class Summary

Nested classes/interfaces inherited from class net.i2p.router.CommSystemFacade

Field Summary

Fields inherited from class net.i2p.router.CommSystemFacade

Constructor Summary

Method Summary

Methods inherited from class net.i2p.router.CommSystemFacade

Methods inherited from class java.lang.Object

Field Detail

PROP_BLOCK_MY_COUNTRY

PROP_IP_COUNTRY

Constructor Detail

CommSystemFacadeImpl

Method Detail

countActivePeers

countActiveSendPeers

countRdnsCacheEntries

createAddresses

enableReverseLookups

enableWhoisLookups

exemptIncoming

forceDisconnect

getCanonicalHostName

getCanonicalHostNameSync

getCompatibleIP

getCountries

getCountry

getCountry

getCountryName

getDomain

getEstablished

getFramedAveragePeerClockSkew

getIP

getLocalizedStatusString

getMostRecentErrorMessages

getOurCountry

getRdnsCacheStats

getStatus

getTransports

getValidIP

getXDHFactory

haveHighOutboundCapacity

haveInboundCapacity

haveOutboundCapacity

initGeoIP

isBacklogged

isDummy

isEstablished

isExemptIncoming

isInStrictCountry

isInStrictCountry

isInStrictCountry

isRunning

mayDisconnect

notifyRemoveAddress

notifyRemoveAddress

notifyReplaceAddress

processMessage

queueLookup

rdnsCacheSize

registerTransport

removeExemption

renderPeerCaps

renderPeerFlag

renderPeerHTML

renderStatusHTML

restart

shutdown

startup

unregisterTransport

wasUnreachable