NetUtil (Netty 4.1.109.Final API文档 - 即时通讯网(52im.net))

java.lang.Object
- io.netty.util.NetUtil

```
public final class NetUtil
extends java.lang.Object
```
A class that holds a number of network-related constants.
This class borrowed some of its methods from a modified fork of the Inet6Util class which was part of Apache Harmony.

字段概要

字段
限定符和类型	字段和说明
`static java.net.InetAddress`	`LOCALHOST` The `InetAddress` that represents the loopback address.
`static java.net.Inet4Address`	`LOCALHOST4` The `Inet4Address` that represents the IPv4 loopback address '127.0.0.1'
`static java.net.Inet6Address`	`LOCALHOST6` The `Inet6Address` that represents the IPv6 loopback address '::1'
`static java.net.NetworkInterface`	`LOOPBACK_IF` The loopback `NetworkInterface` of the current machine
`static java.util.Collection<java.net.NetworkInterface>`	`NETWORK_INTERFACES` An unmodifiable Collection of all the interfaces on this machine.
`static int`	`SOMAXCONN` The SOMAXCONN value of the current machine.

方法概要

All Methods Static Methods Concrete Methods
限定符和类型	方法和说明
`static java.lang.String`	`bytesToIpAddress(byte[] bytes)` Converts 4-byte or 16-byte data into an IPv4 or IPv6 string respectively.
`static java.lang.String`	`bytesToIpAddress(byte[] bytes, int offset, int length)` Converts 4-byte or 16-byte data into an IPv4 or IPv6 string respectively.
`static byte[]`	`createByteArrayFromIpAddressString(java.lang.String ipAddressString)` Creates an byte[] based on an ipAddressString.
`static java.net.InetAddress`	`createInetAddressFromIpAddressString(java.lang.String ipAddressString)` Creates an `InetAddress` based on an ipAddressString or might return null if it can't be parsed.
`static java.net.Inet6Address`	`getByName(java.lang.CharSequence ip)` Returns the `Inet6Address` representation of a `CharSequence` IP address.
`static java.net.Inet6Address`	`getByName(java.lang.CharSequence ip, boolean ipv4Mapped)` Returns the `Inet6Address` representation of a `CharSequence` IP address.
`static java.lang.String`	`getHostname(java.net.InetSocketAddress addr)` Returns `InetSocketAddress.getHostString()` if Java >= 7, or `InetSocketAddress.getHostName()` otherwise.
`static java.lang.String`	`intToIpAddress(int i)` Converts a 32-bit integer into an IPv4 address.
`static int`	`ipv4AddressToInt(java.net.Inet4Address ipAddress)` Convert `Inet4Address` into `int`
`static boolean`	`isIpV4StackPreferred()` Returns `true` if IPv4 should be used even if the system supports both IPv4 and IPv6.
`static boolean`	`isIpV6AddressesPreferred()` Returns `true` if an IPv6 address should be preferred when a host has both an IPv4 address and an IPv6 address.
`static boolean`	`isValidIpV4Address(java.lang.CharSequence ip)` Takes a `CharSequence` and parses it to see if it is a valid IPV4 address.
`static boolean`	`isValidIpV4Address(java.lang.String ip)` Takes a `String` and parses it to see if it is a valid IPV4 address.
`static boolean`	`isValidIpV6Address(java.lang.CharSequence ip)`
`static boolean`	`isValidIpV6Address(java.lang.String ip)`
`static java.lang.String`	`toAddressString(java.net.InetAddress ip)` Returns the `String` representation of an `InetAddress`.
`static java.lang.String`	`toAddressString(java.net.InetAddress ip, boolean ipv4Mapped)` Returns the `String` representation of an `InetAddress`.
`static java.lang.String`	`toSocketAddressString(java.net.InetSocketAddress addr)` Returns the `String` representation of an `InetSocketAddress`.
`static java.lang.String`	`toSocketAddressString(java.lang.String host, int port)` Returns the `String` representation of a host port combo.

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- 字段详细资料
  - LOCALHOST4
```
public static final java.net.Inet4Address LOCALHOST4
```
    The Inet4Address that represents the IPv4 loopback address '127.0.0.1'
  - LOCALHOST6
```
public static final java.net.Inet6Address LOCALHOST6
```
    The Inet6Address that represents the IPv6 loopback address '::1'
  - LOCALHOST
```
public static final java.net.InetAddress LOCALHOST
```
    The InetAddress that represents the loopback address. If IPv6 stack is available, it will refer to LOCALHOST6. Otherwise, LOCALHOST4.
  - LOOPBACK_IF
```
public static final java.net.NetworkInterface LOOPBACK_IF
```
    The loopback NetworkInterface of the current machine
  - NETWORK_INTERFACES
```
public static final java.util.Collection<java.net.NetworkInterface> NETWORK_INTERFACES
```
    An unmodifiable Collection of all the interfaces on this machine.
  - SOMAXCONN
```
public static final int SOMAXCONN
```
    The SOMAXCONN value of the current machine. If failed to get the value, 200 is used as a default value for Windows and 128 for others.
- 方法详细资料
  - isIpV4StackPreferred
```
public static boolean isIpV4StackPreferred()
```
    Returns true if IPv4 should be used even if the system supports both IPv4 and IPv6. Setting this property to true will disable IPv6 support. The default value of this property is false.
    
    另请参阅:
    
    Java SE networking properties
  - isIpV6AddressesPreferred
```
public static boolean isIpV6AddressesPreferred()
```
    Returns true if an IPv6 address should be preferred when a host has both an IPv4 address and an IPv6 address. The default value of this property is false.
    
    另请参阅:
    
    Java SE networking properties
  - createByteArrayFromIpAddressString
```
public static byte[] createByteArrayFromIpAddressString(java.lang.String ipAddressString)
```
    Creates an byte[] based on an ipAddressString. No error handling is performed here.
  - createInetAddressFromIpAddressString
```
public static java.net.InetAddress createInetAddressFromIpAddressString(java.lang.String ipAddressString)
```
    Creates an InetAddress based on an ipAddressString or might return null if it can't be parsed. No error handling is performed here.
  - ipv4AddressToInt
```
public static int ipv4AddressToInt(java.net.Inet4Address ipAddress)
```
    Convert Inet4Address into int
  - intToIpAddress
```
public static java.lang.String intToIpAddress(int i)
```
    Converts a 32-bit integer into an IPv4 address.
  - bytesToIpAddress
```
public static java.lang.String bytesToIpAddress(byte[] bytes)
```
    Converts 4-byte or 16-byte data into an IPv4 or IPv6 string respectively.
    
    抛出:
    
    java.lang.IllegalArgumentException - if length is not 4 nor 16
  - bytesToIpAddress
```
public static java.lang.String bytesToIpAddress(byte[] bytes,
                                                int offset,
                                                int length)
```
    Converts 4-byte or 16-byte data into an IPv4 or IPv6 string respectively.
    
    抛出:
    
    java.lang.IllegalArgumentException - if length is not 4 nor 16
  - isValidIpV6Address
```
public static boolean isValidIpV6Address(java.lang.String ip)
```
  - isValidIpV6Address
```
public static boolean isValidIpV6Address(java.lang.CharSequence ip)
```
  - isValidIpV4Address
```
public static boolean isValidIpV4Address(java.lang.CharSequence ip)
```
    Takes a CharSequence and parses it to see if it is a valid IPV4 address.
    
    返回:
    
    true, if the string represents an IPV4 address in dotted notation, false otherwise
  - isValidIpV4Address
```
public static boolean isValidIpV4Address(java.lang.String ip)
```
    Takes a String and parses it to see if it is a valid IPV4 address.
    
    返回:
    
    true, if the string represents an IPV4 address in dotted notation, false otherwise
  - getByName
```
public static java.net.Inet6Address getByName(java.lang.CharSequence ip)
```
    Returns the Inet6Address representation of a CharSequence IP address.
    This method will treat all IPv4 type addresses as "IPv4 mapped" (see getByName(CharSequence, boolean))
    
    参数:
    
    ip - CharSequence IP address to be converted to a Inet6Address
    
    返回:
    
    Inet6Address representation of the ip or null if not a valid IP address.
  - getByName
```
public static java.net.Inet6Address getByName(java.lang.CharSequence ip,
                                              boolean ipv4Mapped)
```
    Returns the Inet6Address representation of a CharSequence IP address.
    The ipv4Mapped parameter specifies how IPv4 addresses should be treated. "IPv4 mapped" format as defined in rfc 4291 section 2 is supported.
    参数:
    
    ip - CharSequence IP address to be converted to a Inet6Address
    ipv4Mapped -
    
    true To allow IPv4 mapped inputs to be translated into Inet6Address
    
    false Consider IPv4 mapped addresses as invalid.
    返回:
    
    Inet6Address representation of the ip or null if not a valid IP address.
  - toSocketAddressString
```
public static java.lang.String toSocketAddressString(java.net.InetSocketAddress addr)
```
    Returns the String representation of an InetSocketAddress.
    The output does not include Scope ID.
    
    参数:
    
    addr - InetSocketAddress to be converted to an address string
    
    返回:
    
    String containing the text-formatted IP address
  - toSocketAddressString
```
public static java.lang.String toSocketAddressString(java.lang.String host,
                                                     int port)
```
    Returns the String representation of a host port combo.
  - toAddressString
```
public static java.lang.String toAddressString(java.net.InetAddress ip)
```
    Returns the String representation of an InetAddress.
    - Inet4Address results are identical to InetAddress.getHostAddress()
    - Inet6Address results adhere to rfc 5952 section 4
    The output does not include Scope ID.
    参数:
    
    ip - InetAddress to be converted to an address string
    
    返回:
    
    String containing the text-formatted IP address
  - toAddressString
```
public static java.lang.String toAddressString(java.net.InetAddress ip,
                                               boolean ipv4Mapped)
```
    Returns the String representation of an InetAddress.
    - Inet4Address results are identical to InetAddress.getHostAddress()
    - Inet6Address results adhere to rfc 5952 section 4 if ipv4Mapped is false. If ipv4Mapped is true then "IPv4 mapped" format from rfc 4291 section 2 will be supported. The compressed result will always obey the compression rules defined in rfc 5952 section 4
    The output does not include Scope ID.
    参数:
    
    ip - InetAddress to be converted to an address string
    ipv4Mapped -
    
    true to stray from strict rfc 5952 and support the "IPv4 mapped" format defined in rfc 4291 section 2 while still following the updated guidelines in rfc 5952 section 4
    
    false to strictly follow rfc 5952
    返回:
    
    String containing the text-formatted IP address
  - getHostname
```
public static java.lang.String getHostname(java.net.InetSocketAddress addr)
```
    Returns InetSocketAddress.getHostString() if Java >= 7, or InetSocketAddress.getHostName() otherwise.
    
    参数:
    
    addr - The address
    
    返回:
    
    the host string

类 NetUtil

字段概要

方法概要

从类继承的方法 java.lang.Object

字段详细资料

LOCALHOST4

LOCALHOST6

LOCALHOST

LOOPBACK_IF

NETWORK_INTERFACES

SOMAXCONN

方法详细资料

isIpV4StackPreferred

isIpV6AddressesPreferred

createByteArrayFromIpAddressString

createInetAddressFromIpAddressString

ipv4AddressToInt

intToIpAddress

bytesToIpAddress

bytesToIpAddress

isValidIpV6Address

isValidIpV6Address

isValidIpV4Address

isValidIpV4Address

getByName

getByName

toSocketAddressString

toSocketAddressString

toAddressString

toAddressString

getHostname