AddressResolverOptions (Vert.x Stack

java.lang.Object
- io.vertx.core.dns.AddressResolverOptions

```
public class AddressResolverOptions
extends Object
```
Configuration options for Vert.x hostname resolver. The resolver uses the local hosts file and performs DNS A and AAAA queries.

Author:

Julien Viet

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`DEFAULT_CACHE_MAX_TIME_TO_LIVE` The default value for the cache max TTL = 0x7fffffff
`static int`	`DEFAULT_CACHE_MIN_TIME_TO_LIVE` The default value for the cache min TTL = 0
`static int`	`DEFAULT_CACHE_NEGATIVE_TIME_TO_LIVE` The default value for the negative cache TTL = 0
`static int`	`DEFAULT_MAX_QUERIES` The default value for the max dns queries per query = 4
`static int`	`DEFAULT_NDOTS` The default ndots value = loads the value from the OS on Linux otherwise use the value 1
`static boolean`	`DEFAULT_OPT_RESOURCE_ENABLED` The default value for `setOptResourceEnabled(boolean)` = false
`static int`	`DEFAULT_QUERY_TIMEOUT` The default value for the query timeout in millis = 5000
`static boolean`	`DEFAULT_RD_FLAG` The default value of the rd flag = true
`static boolean`	`DEFAULT_ROTATE_SERVERS` The default servers rotate value = loads the value from the OS on Linux otherwise use the value false
`static boolean`	`DEFAULT_ROUND_ROBIN_INET_ADDRESS` The default round robin inet address = false
`static List<String>`	`DEFAULT_SEACH_DOMAINS` The default value of search domains = null
`static List<String>`	`DEFAULT_SERVERS` The default list of DNS servers = null (uses system name server's list like resolve.conf otherwise Google Public DNS)

Constructor Summary

Constructors
Constructor and Description

AddressResolverOptions()

AddressResolverOptions(AddressResolverOptions other)

AddressResolverOptions(JsonObject json)

Constructors
Constructor and Description
`AddressResolverOptions()`
`AddressResolverOptions(AddressResolverOptions other)`
`AddressResolverOptions(JsonObject json)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`AddressResolverOptions`	`addSearchDomain(String searchDomain)` Add a DNS search domain.
`AddressResolverOptions`	`addServer(String server)` Add a DNS server address.
`int`	`getCacheMaxTimeToLive()`
`int`	`getCacheMinTimeToLive()`
`int`	`getCacheNegativeTimeToLive()`
`String`	`getHostsPath()`
`Buffer`	`getHostsValue()`
`int`	`getMaxQueries()`
`int`	`getNdots()`
`long`	`getQueryTimeout()`
`boolean`	`getRdFlag()`
`List<String>`	`getSearchDomains()`
`List<String>`	`getServers()`
`boolean`	`isOptResourceEnabled()`
`boolean`	`isRotateServers()`
`boolean`	`isRoundRobinInetAddress()`
`AddressResolverOptions`	`setCacheMaxTimeToLive(int cacheMaxTimeToLive)` Set the cache maximum TTL value in seconds.
`AddressResolverOptions`	`setCacheMinTimeToLive(int cacheMinTimeToLive)` Set the cache minimum TTL value in seconds.
`AddressResolverOptions`	`setCacheNegativeTimeToLive(int cacheNegativeTimeToLive)` Set the negative cache TTL value in seconds.
`AddressResolverOptions`	`setHostsPath(String hostsPath)` Set the path of an alternate hosts configuration file to use instead of the one provided by the os.
`AddressResolverOptions`	`setHostsValue(Buffer hostsValue)` Set an alternate hosts configuration file to use instead of the one provided by the os.
`AddressResolverOptions`	`setMaxQueries(int maxQueries)` Set the maximum number of queries when an hostname is resolved.
`AddressResolverOptions`	`setNdots(int ndots)` Set the ndots value used when resolving using search domains, the default value is `-1` which determines the value from the OS on Linux or uses the value `1`.
`AddressResolverOptions`	`setOptResourceEnabled(boolean optResourceEnabled)` Set to true to enable the automatic inclusion in DNS queries of an optional record that hints the remote DNS server about how much data the resolver can read per response.
`AddressResolverOptions`	`setQueryTimeout(long queryTimeout)` Set the query timeout in milliseconds, i.e the amount of time after a query is considered to be failed.
`AddressResolverOptions`	`setRdFlag(boolean rdFlag)` Set the DNS queries Recursion Desired flag value.
`AddressResolverOptions`	`setRotateServers(boolean rotateServers)` Set to `true` to enable round-robin selection of the dns server to use.
`AddressResolverOptions`	`setRoundRobinInetAddress(boolean roundRobinInetAddress)` Set to `true` to enable round-robin inet address selection of the ip address to use.
`AddressResolverOptions`	`setSearchDomains(List<String> searchDomains)` Set the lists of DNS search domains.
`AddressResolverOptions`	`setServers(List<String> servers)` Set the list of DNS server addresses, an address is the IP of the dns server, followed by an optional colon and a port, e.g `8.8.8.8` or {code 192.168.0.1:40000}.
`JsonObject`	`toJson()`

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

- Field Detail
  - DEFAULT_SERVERS
```
public static final List<String> DEFAULT_SERVERS
```
    The default list of DNS servers = null (uses system name server's list like resolve.conf otherwise Google Public DNS)
  - DEFAULT_OPT_RESOURCE_ENABLED
```
public static final boolean DEFAULT_OPT_RESOURCE_ENABLED
```
    The default value for setOptResourceEnabled(boolean) = false
    
    See Also:
    
    Constant Field Values
  - DEFAULT_CACHE_MIN_TIME_TO_LIVE
```
public static final int DEFAULT_CACHE_MIN_TIME_TO_LIVE
```
    The default value for the cache min TTL = 0
    
    See Also:
    
    Constant Field Values
  - DEFAULT_CACHE_MAX_TIME_TO_LIVE
```
public static final int DEFAULT_CACHE_MAX_TIME_TO_LIVE
```
    The default value for the cache max TTL = 0x7fffffff
    
    See Also:
    
    Constant Field Values
  - DEFAULT_CACHE_NEGATIVE_TIME_TO_LIVE
```
public static final int DEFAULT_CACHE_NEGATIVE_TIME_TO_LIVE
```
    The default value for the negative cache TTL = 0
    
    See Also:
    
    Constant Field Values
  - DEFAULT_QUERY_TIMEOUT
```
public static final int DEFAULT_QUERY_TIMEOUT
```
    The default value for the query timeout in millis = 5000
    
    See Also:
    
    Constant Field Values
  - DEFAULT_MAX_QUERIES
```
public static final int DEFAULT_MAX_QUERIES
```
    The default value for the max dns queries per query = 4
    
    See Also:
    
    Constant Field Values
  - DEFAULT_RD_FLAG
```
public static final boolean DEFAULT_RD_FLAG
```
    The default value of the rd flag = true
    
    See Also:
    
    Constant Field Values
  - DEFAULT_SEACH_DOMAINS
```
public static final List<String> DEFAULT_SEACH_DOMAINS
```
    The default value of search domains = null
  - DEFAULT_NDOTS
```
public static final int DEFAULT_NDOTS
```
    The default ndots value = loads the value from the OS on Linux otherwise use the value 1
  - DEFAULT_ROTATE_SERVERS
```
public static final boolean DEFAULT_ROTATE_SERVERS
```
    The default servers rotate value = loads the value from the OS on Linux otherwise use the value false
  - DEFAULT_ROUND_ROBIN_INET_ADDRESS
```
public static final boolean DEFAULT_ROUND_ROBIN_INET_ADDRESS
```
    The default round robin inet address = false
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - AddressResolverOptions
```
public AddressResolverOptions()
```
  - AddressResolverOptions
```
public AddressResolverOptions(AddressResolverOptions other)
```
  - AddressResolverOptions
```
public AddressResolverOptions(JsonObject json)
```
- Method Detail
  - getHostsPath
```
public String getHostsPath()
```
    Returns:
    
    the path to the alternate hosts configuration file
  - setHostsPath
```
public AddressResolverOptions setHostsPath(String hostsPath)
```
    Set the path of an alternate hosts configuration file to use instead of the one provided by the os.
    The default value is null, so the operating system hosts config is used.
    
    Parameters:
    
    hostsPath - the hosts path
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - getHostsValue
```
public Buffer getHostsValue()
```
    Returns:
    
    the hosts configuration file value
  - setHostsValue
```
public AddressResolverOptions setHostsValue(Buffer hostsValue)
```
    Set an alternate hosts configuration file to use instead of the one provided by the os.
    The value should contain the hosts content literaly, for instance 127.0.0.1 localhost
    The default value is null, so the operating system hosts config is used.
    
    Parameters:
    
    hostsValue - the hosts content
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - getServers
```
public List<String> getServers()
```
    Returns:
    
    the list of dns server
  - setServers
```
public AddressResolverOptions setServers(List<String> servers)
```
    Set the list of DNS server addresses, an address is the IP of the dns server, followed by an optional colon and a port, e.g 8.8.8.8 or {code 192.168.0.1:40000}. When the list is empty, the resolver will use the list of the system DNS server addresses from the environment, if that list cannot be retrieved it will use Google's public DNS servers "8.8.8.8" and "8.8.4.4".
    
    Parameters:
    
    servers - the list of DNS servers
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - addServer
```
public AddressResolverOptions addServer(String server)
```
    Add a DNS server address.
    
    Parameters:
    
    server - the server to add
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - isOptResourceEnabled
```
public boolean isOptResourceEnabled()
```
    Returns:
    
    true if an optional record is automatically included in DNS queries
  - setOptResourceEnabled
```
public AddressResolverOptions setOptResourceEnabled(boolean optResourceEnabled)
```
    Set to true to enable the automatic inclusion in DNS queries of an optional record that hints the remote DNS server about how much data the resolver can read per response.
    
    Parameters:
    
    optResourceEnabled - true to enable, false otherwise
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - getCacheMinTimeToLive
```
public int getCacheMinTimeToLive()
```
    Returns:
    
    the cache min TTL in seconds
  - setCacheMinTimeToLive
```
public AddressResolverOptions setCacheMinTimeToLive(int cacheMinTimeToLive)
```
    Set the cache minimum TTL value in seconds. After resolution successful IP addresses are cached with their DNS response TTL, use this to set a minimum value to all responses TTL.
    
    Parameters:
    
    cacheMinTimeToLive - the cache min TTL in seconds
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - getCacheMaxTimeToLive
```
public int getCacheMaxTimeToLive()
```
    Returns:
    
    the cache max TTL in seconds
  - setCacheMaxTimeToLive
```
public AddressResolverOptions setCacheMaxTimeToLive(int cacheMaxTimeToLive)
```
    Set the cache maximum TTL value in seconds. After successful resolution IP addresses are cached with their DNS response TTL, use this to set a maximum value to all responses TTL.
    
    Parameters:
    
    cacheMaxTimeToLive - the cache max TTL in seconds
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - getCacheNegativeTimeToLive
```
public int getCacheNegativeTimeToLive()
```
    Returns:
    
    the cache negative TTL in seconds
  - setCacheNegativeTimeToLive
```
public AddressResolverOptions setCacheNegativeTimeToLive(int cacheNegativeTimeToLive)
```
    Set the negative cache TTL value in seconds. After a failed hostname resolution, DNS queries won't be retried for a period of time equals to the negative TTL. This allows to reduce the response time of negative replies and reduce the amount of messages to DNS servers.
    
    Parameters:
    
    cacheNegativeTimeToLive - the cache negative TTL in seconds
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - getQueryTimeout
```
public long getQueryTimeout()
```
    Returns:
    
    the query timeout in milliseconds
  - setQueryTimeout
```
public AddressResolverOptions setQueryTimeout(long queryTimeout)
```
    Set the query timeout in milliseconds, i.e the amount of time after a query is considered to be failed.
    
    Parameters:
    
    queryTimeout - the query timeout in milliseconds
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - getMaxQueries
```
public int getMaxQueries()
```
    Returns:
    
    the maximum number of queries to be sent during a resolution
  - setMaxQueries
```
public AddressResolverOptions setMaxQueries(int maxQueries)
```
    Set the maximum number of queries when an hostname is resolved.
    
    Parameters:
    
    maxQueries - the max number of queries to be sent
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - getRdFlag
```
public boolean getRdFlag()
```
    Returns:
    
    the DNS queries Recursion Desired flag value
  - setRdFlag
```
public AddressResolverOptions setRdFlag(boolean rdFlag)
```
    Set the DNS queries Recursion Desired flag value.
    
    Parameters:
    
    rdFlag - the flag value
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - getSearchDomains
```
public List<String> getSearchDomains()
```
    Returns:
    
    the list of search domains
  - setSearchDomains
```
public AddressResolverOptions setSearchDomains(List<String> searchDomains)
```
    Set the lists of DNS search domains.
    When the search domain list is null, the effective search domain list will be populated using the system DNS search domains.
    
    Parameters:
    
    searchDomains - the search domains
  - addSearchDomain
```
public AddressResolverOptions addSearchDomain(String searchDomain)
```
    Add a DNS search domain.
    
    Parameters:
    
    searchDomain - the search domain to add
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - getNdots
```
public int getNdots()
```
    Returns:
    
    the ndots value
  - setNdots
```
public AddressResolverOptions setNdots(int ndots)
```
    Set the ndots value used when resolving using search domains, the default value is -1 which determines the value from the OS on Linux or uses the value 1.
    
    Parameters:
    
    ndots - the new ndots value
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - isRotateServers
```
public boolean isRotateServers()
```
    Returns:
    
    the value true when the dns server selection uses round robin
  - setRotateServers
```
public AddressResolverOptions setRotateServers(boolean rotateServers)
```
    Set to true to enable round-robin selection of the dns server to use. It spreads the query load among the servers and avoids all lookup to hit the first server of the list.
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - isRoundRobinInetAddress
```
public boolean isRoundRobinInetAddress()
```
    Returns:
    
    the value true when the inet address selection uses round robin
  - setRoundRobinInetAddress
```
public AddressResolverOptions setRoundRobinInetAddress(boolean roundRobinInetAddress)
```
    Set to true to enable round-robin inet address selection of the ip address to use.
    
    Returns:
    
    a reference to this, so the API can be used fluently
  - toJson
```
public JsonObject toJson()
```

Class AddressResolverOptions

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_SERVERS

DEFAULT_OPT_RESOURCE_ENABLED

DEFAULT_CACHE_MIN_TIME_TO_LIVE

DEFAULT_CACHE_MAX_TIME_TO_LIVE

DEFAULT_CACHE_NEGATIVE_TIME_TO_LIVE

DEFAULT_QUERY_TIMEOUT

DEFAULT_MAX_QUERIES

DEFAULT_RD_FLAG

DEFAULT_SEACH_DOMAINS

DEFAULT_NDOTS

DEFAULT_ROTATE_SERVERS

DEFAULT_ROUND_ROBIN_INET_ADDRESS

Constructor Detail

AddressResolverOptions

AddressResolverOptions

AddressResolverOptions

Method Detail

getHostsPath

setHostsPath

getHostsValue

setHostsValue

getServers

setServers

addServer

isOptResourceEnabled

setOptResourceEnabled

getCacheMinTimeToLive

setCacheMinTimeToLive

getCacheMaxTimeToLive

setCacheMaxTimeToLive

getCacheNegativeTimeToLive

setCacheNegativeTimeToLive

getQueryTimeout

setQueryTimeout

getMaxQueries

setMaxQueries

getRdFlag

setRdFlag

getSearchDomains

setSearchDomains

addSearchDomain

getNdots

setNdots

isRotateServers

setRotateServers

isRoundRobinInetAddress

setRoundRobinInetAddress

toJson