com.facebook.presto.spi

Class HostAddress

java.lang.Object

com.facebook.presto.spi.HostAddress

public class HostAddress
extends Object

An immutable representation of a host and port.

Example usage:

 HostAndPort hp = HostAndPort.fromString("[2001:db8::1]")
     .withDefaultPort(80)
     .requireBracketsForIPv6();
 hp.getHostText();  // returns "2001:db8::1"
 hp.getPort();      // returns 80
 hp.toString();     // returns "[2001:db8::1]:80"
 

Here are some examples of recognized formats:

• example.com
• example.com:80
• 192.0.2.1
• 192.0.2.1:80
• [2001:db8::1] - getHostText() omits brackets
• [2001:db8::1]:80 - getHostText() omits brackets
• 2001:db8::1 - Use requireBracketsForIPv6() to prohibit this

Note that this is not an exhaustive list, because these methods are only concerned with brackets, colons, and port numbers. Full validation of the host field (if desired) is the caller's responsibility.

Since:

10.0

Author:

Paul Marks

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object obj)
static HostAddress	fromParts(String host, int port) Build a HostAddress instance from separate host and port values.
static HostAddress	fromString(String hostPortString) Split a freeform string into a host and port, without strict validation.
static HostAddress	fromUri(URI httpUri)
String	getHostText() Returns the portion of this HostAddress instance that should represent the hostname or IPv4/IPv6 literal.
int	getPort() Get the current port number, failing if no port is defined.
int	getPortOrDefault(int defaultPort) Returns the current port number, with a default if no port is defined.
int	hashCode()
boolean	hasPort() Return true if this instance has a defined port.
HostAddress	requireBracketsForIPv6() Generate an error if the host might be a non-bracketed IPv6 literal.
InetAddress	toInetAddress()
String	toString() Rebuild the host:port string, including brackets if necessary.
HostAddress	withDefaultPort(int defaultPort) Provide a default port if the parsed string contained only a host.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

getHostText

public String getHostText()

Returns the portion of this HostAddress instance that should represent the hostname or IPv4/IPv6 literal.

A successful parse does not imply any degree of sanity in this field. For additional validation, see the com.google.common.net.HostSpecifier class.

hasPort

public boolean hasPort()

Return true if this instance has a defined port.

getPort

public int getPort()

Get the current port number, failing if no port is defined.

Returns:

a validated port number, in the range [0..65535]

Throws:

IllegalStateException - if no port is defined. You can use withDefaultPort(int) to prevent this from occurring.

getPortOrDefault

public int getPortOrDefault(int defaultPort)

Returns the current port number, with a default if no port is defined.

fromParts

public static HostAddress fromParts(String host,
                    int port)

Build a HostAddress instance from separate host and port values.

Note: Non-bracketed IPv6 literals are allowed. Use requireBracketsForIPv6() to prohibit these.

Parameters:

host - the host string to parse. Must not contain a port number.

port - a port number from [0..65535]

Returns:

if parsing was successful, a populated HostAddress object.

Throws:

IllegalArgumentException - if host contains a port number, or port is out of range.

fromString

public static HostAddress fromString(String hostPortString)

Split a freeform string into a host and port, without strict validation.

Note that the host-only formats will leave the port field undefined. You can use withDefaultPort(int) to patch in a default value.

Parameters:

hostPortString - the input string to parse.

Returns:

if parsing was successful, a populated HostAddress object.

Throws:

IllegalArgumentException - if nothing meaningful could be parsed.

fromUri

public static HostAddress fromUri(URI httpUri)

withDefaultPort

public HostAddress withDefaultPort(int defaultPort)

Provide a default port if the parsed string contained only a host.

You can chain this after fromString(String) to include a port in case the port was omitted from the input string. If a port was already provided, then this method is a no-op.

Parameters:

defaultPort - a port number, from [0..65535]

Returns:

a HostAddress instance, guaranteed to have a defined port.

requireBracketsForIPv6

public HostAddress requireBracketsForIPv6()

Generate an error if the host might be a non-bracketed IPv6 literal.

URI formatting requires that IPv6 literals be surrounded by brackets, like "[2001:db8::1]". Chain this call after fromString(String) to increase the strictness of the parser, and disallow IPv6 literals that don't contain these brackets.

Note that this parser identifies IPv6 literals solely based on the presence of a colon. To perform actual validation of IP addresses, see the com.google.common.net.InetAddresses#forString(String) method.

Returns:

this, to enable chaining of calls.

Throws:

IllegalArgumentException - if bracketless IPv6 is detected.

toInetAddress

public InetAddress toInetAddress()
                          throws UnknownHostException

Throws:

UnknownHostException

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

toString

public String toString()

Rebuild the host:port string, including brackets if necessary.

Overrides:

toString in class Object