Utility classes to handle IPv4 addresses

This commit is contained in:
Marc Baloup 2024-02-16 12:59:12 +01:00
parent 2d6d905b54
commit e4eb6dc9c9
2 changed files with 174 additions and 0 deletions

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package fr.pandacube.lib.util.network;
import java.net.Inet4Address;
/**
* Represents an IPv4 address.
*/
public class IPv4Address {
private final int address;
/**
* Creates an IPv4 from the binary content of the provided integer.
* @param address the integer used for the 32 bits of the address.
*/
public IPv4Address(int address) {
this.address = address;
}
/**
* Creates an IPv4 from the binary content of the provided bytes.
* @param address the 4 bytes used for the address. The byte at index 0 contains the most significant bits of the
* address.
*/
public IPv4Address(byte[] address) {
this((checkIPv4ByteArray(address)[0] << 24)
| (address[1] << 16)
| (address[2] << 8)
| address[3]);
}
/**
* Creates an IPv4 from the 4 provided integers.
* @param b0 the most significant byte of the address.
* Only the 8 least significant bits of this integer will be used.
* @param b1 the second most significant byte of the address.
* Only the 8 least significant bits of this integer will be used.
* @param b2 the third most significant byte of the address.
* Only the 8 least significant bits of this integer will be used.
* @param b3 the least significant byte of the address.
* Only the 8 least significant bits of this integer will be used.
*/
public IPv4Address(int b0, int b1, int b2, int b3) {
this(((b0 & 0xFF) << 24)
| ((b1 & 0xFF) << 16)
| ((b2 & 0xFF) << 8)
| ((b3 & 0xFF)));
}
/**
* Creates an IPv4 from the provided {@link java.net.Inet4Address}.
* @param address the {@link java.net.Inet4Address}.
*/
public IPv4Address(Inet4Address address) {
this(address.getAddress());
}
private static byte[] checkIPv4ByteArray(byte[] address) {
if (address == null || address.length != 4)
throw new IllegalArgumentException("address must not be null and be of length 4.");
return address;
}
/**
* Gets the bytes of this IPv4 address.
* <p>
* The byte at index 0 contains the most significant bits of the address.
* @return the bytes of this IPv4 address.
*/
public byte[] getByteArray() {
return new byte[] {
(byte) (address >> 24 & 0xFF),
(byte) (address >> 16 & 0xFF),
(byte) (address >> 8 & 0xFF),
(byte) (address & 0xFF)
};
}
/**
* Gets the bytes of this IPv4 address represented as integers.
* <p>
* The byte at index 0 contains the most significant bits of the address.
* @return the bytes of this IPv4 address represented as integers.
*/
public int[] getIntArray() {
return new int[] {
address >> 24 & 0xFF,
address >> 16 & 0xFF,
address >> 8 & 0xFF,
address & 0xFF
};
}
/**
* Creates a new IPv4 address with only the network bits sets according to this IPv4 address.
* @param networkBits the bits count of the network part of the returned address. Must be between 0 and 32 inclusive.
* @return a new IPv4 address.
*/
public IPv4Address asNetworkAddress(int networkBits) {
if (networkBits < 0 || networkBits > 32)
throw new IllegalArgumentException("invalid network bits count: " + networkBits);
int shift = 32 - networkBits;
return new IPv4Address(address >> shift << shift);
}
/**
* Creates a new IPv4 address with only the host bits sets according to this IPv4 address.
* @param networkBits the bits count of the network part of the returned address. Must be between 0 and 32 inclusive.
* @return a new IPv4 address.
*/
public IPv4Address asHostAddress(int networkBits) {
if (networkBits < 0 || networkBits > 32)
throw new IllegalArgumentException("invalid network bits count: " + networkBits);
return new IPv4Address(address << networkBits >> networkBits);
}
@Override
public String toString() {
int[] Parts = getIntArray();
return Parts[0] + "." + Parts[1] + "." + Parts[2] + "." + Parts[3];
}
@Override
public boolean equals(Object o) {
return o == this || (o instanceof IPv4Address other && address == other.address);
}
@Override
public int hashCode() {
return address;
}
}

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package fr.pandacube.lib.util.network;
/**
* Represents an IPv4 network address (an IP address and a network mask).
*/
public class IPv4Network {
private final IPv4Address networkAddress;
private final int bits;
/**
* Creates a new IPv4 network address.
* @param networkAddress the address.
* @param bits the bits count of the network part of the address. Must be between 0 and 32 inclusive.
*/
public IPv4Network(IPv4Address networkAddress, int bits) {
if (networkAddress == null)
throw new IllegalArgumentException("networkAddress cannot be null.");
if (bits < 0 || bits > 32)
throw new IllegalArgumentException("invalid network bits count: " + bits);
this.networkAddress = networkAddress.asNetworkAddress(bits);
this.bits = bits;
}
/**
* Telles if the provided {@link IPv4Address} is part of this network.
* @param address the provided IPv4 address.
* @return true if the provided {@link IPv4Address} is part of this network, false otherwise.
*/
public boolean isInNetwork(IPv4Address address) {
return address.asNetworkAddress(bits).equals(networkAddress);
}
}