HostAddress.java
/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.facebook.presto.spi;
import com.facebook.drift.annotations.ThriftConstructor;
import com.facebook.drift.annotations.ThriftField;
import com.facebook.drift.annotations.ThriftStruct;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonValue;
import java.net.InetAddress;
import java.net.URI;
import java.net.UnknownHostException;
import java.util.Objects;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import static java.util.Objects.requireNonNull;
/**
* An immutable representation of a host and port.
* <p>
* <p>Example usage:
* <pre>
* 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"
* </pre>
* <p>
* <p>Here are some examples of recognized formats:
* <ul>
* <li>example.com
* <li>example.com:80
* <li>192.0.2.1
* <li>192.0.2.1:80
* <li>[2001:db8::1] - {@link #getHostText()} omits brackets
* <li>[2001:db8::1]:80 - {@link #getHostText()} omits brackets
* <li>2001:db8::1
* </ul>
* <p>
* <p>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.
*
* @author Paul Marks
* @since 10.0
*/
@ThriftStruct
public class HostAddress
{
/**
* Magic value indicating the absence of a port number.
*/
private static final int NO_PORT = -1;
/**
* Hostname, IPv4/IPv6 literal, or unvalidated nonsense.
*/
private final String host;
/**
* Validated port number in the range [0..65535], or NO_PORT
*/
private final int port;
@ThriftConstructor
public HostAddress(String hostPortString)
{
HostAddress parsedAddress = fromString(hostPortString);
this.host = parsedAddress.host;
this.port = parsedAddress.port;
}
public HostAddress(String host, int port)
{
this.host = host;
this.port = port;
}
/**
* Returns the portion of this {@code HostAddress} instance that should
* represent the hostname or IPv4/IPv6 literal.
* <p>
* <p>A successful parse does not imply any degree of sanity in this field.
* For additional validation, see the {@link com.google.common.net.HostSpecifier} class.
*/
public String getHostText()
{
return host;
}
/**
* Return true if this instance has a defined port.
*/
public boolean hasPort()
{
return port >= 0;
}
/**
* Get the current port number, failing if no port is defined.
*
* @return a validated port number, in the range [0..65535]
* @throws IllegalStateException if no port is defined. You can use
* {@link #withDefaultPort(int)} to prevent this from occurring.
*/
public int getPort()
{
if (!hasPort()) {
throw new IllegalStateException("no port");
}
return port;
}
/**
* Returns the current port number, with a default if no port is defined.
*/
public int getPortOrDefault(int defaultPort)
{
return hasPort() ? port : defaultPort;
}
/**
* Build a HostAddress instance from separate host and port values.
* <p>
* <p>Note: Non-bracketed IPv6 literals are allowed.
*
* @param host the host string to parse. Must not contain a port number.
* @param port a port number from [0..65535]
* @return if parsing was successful, a populated HostAddress object.
* @throws IllegalArgumentException if {@code host} contains a port number,
* or {@code port} is out of range.
*/
public static HostAddress fromParts(String host, int port)
{
if (!isValidPort(port)) {
throw new IllegalArgumentException("Port is invalid: " + port);
}
HostAddress parsedHost = fromString(host);
if (parsedHost.hasPort()) {
throw new IllegalArgumentException("host contains a port declaration: " + host);
}
return new HostAddress(parsedHost.host, port);
}
private static final Pattern BRACKET_PATTERN = Pattern.compile("^\\[(.*:.*)\\](?::(\\d*))?$");
/**
* Split a freeform string into a host and port, without strict validation.
* <p>
* Note that the host-only formats will leave the port field undefined. You
* can use {@link #withDefaultPort(int)} to patch in a default value.
*
* @param hostPortString the input string to parse.
* @return if parsing was successful, a populated HostAddress object.
* @throws IllegalArgumentException if nothing meaningful could be parsed.
*/
@JsonCreator
public static HostAddress fromString(String hostPortString)
{
requireNonNull(hostPortString, "hostPortString is null");
String host;
String portString = null;
if (hostPortString.startsWith("[")) {
// Parse a bracketed host, typically an IPv6 literal.
Matcher matcher = BRACKET_PATTERN.matcher(hostPortString);
if (!matcher.matches()) {
throw new IllegalArgumentException("Invalid bracketed host/port: " + hostPortString);
}
host = matcher.group(1);
portString = matcher.group(2); // could be null
}
else {
int colonPos = hostPortString.indexOf(':');
if (colonPos >= 0 && hostPortString.indexOf(':', colonPos + 1) == -1) {
// Exactly 1 colon. Split into host:port.
host = hostPortString.substring(0, colonPos);
portString = hostPortString.substring(colonPos + 1);
}
else {
// 0 or 2+ colons. Bare hostname or IPv6 literal.
host = hostPortString;
}
}
int port = NO_PORT;
if (portString != null && portString.length() != 0) {
// Try to parse the whole port string as a number.
// JDK7 accepts leading plus signs. We don't want to.
if (portString.startsWith("+")) {
throw new IllegalArgumentException("Unparseable port number: " + hostPortString);
}
try {
port = Integer.parseInt(portString);
}
catch (NumberFormatException e) {
throw new IllegalArgumentException("Unparseable port number: " + hostPortString);
}
if (!isValidPort(port)) {
throw new IllegalArgumentException("Port number out of range: " + hostPortString);
}
}
return new HostAddress(host, port);
}
public static HostAddress fromUri(URI httpUri)
{
String host = httpUri.getHost();
int port = httpUri.getPort();
if (port < 0) {
return fromString(host);
}
else {
return fromParts(host, port);
}
}
/**
* Provide a default port if the parsed string contained only a host.
* <p>
* You can chain this after {@link #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.
*
* @param defaultPort a port number, from [0..65535]
* @return a HostAddress instance, guaranteed to have a defined port.
*/
public HostAddress withDefaultPort(int defaultPort)
{
if (!isValidPort(defaultPort)) {
throw new IllegalArgumentException("Port number out of range: " + defaultPort);
}
if (hasPort() || port == defaultPort) {
return this;
}
return new HostAddress(host, defaultPort);
}
public InetAddress toInetAddress()
throws UnknownHostException
{
return InetAddress.getByName(getHostText());
}
@Override
public int hashCode()
{
return Objects.hash(host, port);
}
@Override
public boolean equals(Object obj)
{
if (this == obj) {
return true;
}
if (obj == null || getClass() != obj.getClass()) {
return false;
}
final HostAddress other = (HostAddress) obj;
return Objects.equals(this.host, other.host) &&
Objects.equals(this.port, other.port);
}
/**
* Rebuild the host:port string, including brackets if necessary.
*/
@JsonValue
@ThriftField(value = 1, name = "hostPortString")
@Override
public String toString()
{
StringBuilder builder = new StringBuilder(host.length() + 7);
if (host.indexOf(':') >= 0) {
builder.append('[').append(host).append(']');
}
else {
builder.append(host);
}
if (hasPort()) {
builder.append(':').append(port);
}
return builder.toString();
}
/**
* Return true for valid port numbers.
*/
private static boolean isValidPort(int port)
{
return port >= 0 && port <= 65535;
}
}