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How to get Subnet from an IP in Java

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0

How do I get the subnet value from an IP Address.
For eg, we can do below in Python. (But how about Java?)

interface = ipaddress.IPv4Interface('11.22.104.0/0.0.0.255')
value = interface.with_prefixlen

Output of value = 11.22.104.0/24

Basically, I need a function to convert 0.0.0.255 into /24. Thanks.

Edit

-Java 7 is used.

java python interface ip subnet

share|improve this question

edited Dec 21 '16 at 7:30

user1841495

asked Dec 21 '16 at 6:32

user1841495user1841495

306

add a comment | 

0

How do I get the subnet value from an IP Address.
For eg, we can do below in Python. (But how about Java?)

interface = ipaddress.IPv4Interface('11.22.104.0/0.0.0.255')
value = interface.with_prefixlen

Output of value = 11.22.104.0/24

Basically, I need a function to convert 0.0.0.255 into /24. Thanks.

Edit

-Java 7 is used.

java python interface ip subnet

share|improve this question

edited Dec 21 '16 at 7:30

user1841495

asked Dec 21 '16 at 6:32

user1841495user1841495

306

add a comment | 

How do I get the subnet value from an IP Address.
For eg, we can do below in Python. (But how about Java?)

interface = ipaddress.IPv4Interface('11.22.104.0/0.0.0.255')
value = interface.with_prefixlen

Output of value = 11.22.104.0/24

Basically, I need a function to convert 0.0.0.255 into /24. Thanks.

Edit

-Java 7 is used.

java python interface ip subnet

share|improve this question

edited Dec 21 '16 at 7:30

user1841495

asked Dec 21 '16 at 6:32

user1841495user1841495

306

interface = ipaddress.IPv4Interface('11.22.104.0/0.0.0.255')
value = interface.with_prefixlen

share|improve this question

edited Dec 21 '16 at 7:30

user1841495

asked Dec 21 '16 at 6:32

user1841495user1841495

306

share|improve this question

edited Dec 21 '16 at 7:30

user1841495

asked Dec 21 '16 at 6:32

user1841495user1841495

306

asked Dec 21 '16 at 6:32

user1841495user1841495

306

asked Dec 21 '16 at 6:32

user1841495user1841495

306

2 Answers
2

active

oldest

votes

1

With Guava:

int slash = Integer.bitCount(
 ~Ints.fromByteArray(
 InetAddresses.forString("0.0.0.255").getAddress()));

With Java 8:

int slash = Arrays.stream("0.0.0.255".split("\."))
 .mapToInt(Integer::parseInt)
 .map(i -> ~i & 0xFF)
 .map(Integer::bitCount)
 .sum();

With Java 7:

int slash = 0;
for (String octet : "0.0.0.255".split("\.")) 
 slash += Integer.bitCount(~Integer.parseInt(octet) & 0xFF);

The value of slash will be 24.

share|improve this answer

edited Dec 21 '16 at 7:32

answered Dec 21 '16 at 7:21

shmoselshmosel

37.2k43997

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Is there any ready-to-use library in Java 7? My application is using Java 7, hence the code provided above is not working. Sorry for never mentioning the Java version.
  
  – user1841495
  Dec 21 '16 at 7:29
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @user1841495 Added a Java 7 version.
  
  – shmosel
  Dec 21 '16 at 7:33
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks for the solution for Java 7, do you mind to make some explanation? I'm going to test with this solution shortly. Thanks a lot.
  
  – user1841495
  Dec 21 '16 at 10:19
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @user1841495 Basically we're converting the IP address to 4 unsigned bytes, then counting the inverted bits (because this is a wildcard mask).
  
  – shmosel
  Dec 21 '16 at 18:09
  

  
  
  
  

add a comment | 

0

The IPAddress Java library supports both IPv4 and IPv6 subnets in a polymorphic manner. Disclaimer: I am the project manager. The following code will convert a host mask to a prefix length:

IPAddressString maskString = new IPAddressString("0.0.0.255");
IPAddress mask = maskString.toAddress();
Integer prefLen = mask.getBlockMaskPrefixLength(false);//24

share|improve this answer

answered Mar 22 at 22:17

Sean FSean F

2,096614

add a comment | 

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1

With Guava:

int slash = Integer.bitCount(
 ~Ints.fromByteArray(
 InetAddresses.forString("0.0.0.255").getAddress()));

With Java 8:

int slash = Arrays.stream("0.0.0.255".split("\."))
 .mapToInt(Integer::parseInt)
 .map(i -> ~i & 0xFF)
 .map(Integer::bitCount)
 .sum();

With Java 7:

int slash = 0;
for (String octet : "0.0.0.255".split("\.")) 
 slash += Integer.bitCount(~Integer.parseInt(octet) & 0xFF);

The value of slash will be 24.

share|improve this answer

edited Dec 21 '16 at 7:32

answered Dec 21 '16 at 7:21

shmoselshmosel

37.2k43997

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Is there any ready-to-use library in Java 7? My application is using Java 7, hence the code provided above is not working. Sorry for never mentioning the Java version.
  
  – user1841495
  Dec 21 '16 at 7:29
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @user1841495 Added a Java 7 version.
  
  – shmosel
  Dec 21 '16 at 7:33
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks for the solution for Java 7, do you mind to make some explanation? I'm going to test with this solution shortly. Thanks a lot.
  
  – user1841495
  Dec 21 '16 at 10:19
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @user1841495 Basically we're converting the IP address to 4 unsigned bytes, then counting the inverted bits (because this is a wildcard mask).
  
  – shmosel
  Dec 21 '16 at 18:09
  

  
  
  
  

add a comment | 

1

With Guava:

int slash = Integer.bitCount(
 ~Ints.fromByteArray(
 InetAddresses.forString("0.0.0.255").getAddress()));

With Java 8:

int slash = Arrays.stream("0.0.0.255".split("\."))
 .mapToInt(Integer::parseInt)
 .map(i -> ~i & 0xFF)
 .map(Integer::bitCount)
 .sum();

With Java 7:

int slash = 0;
for (String octet : "0.0.0.255".split("\.")) 
 slash += Integer.bitCount(~Integer.parseInt(octet) & 0xFF);

The value of slash will be 24.

share|improve this answer

edited Dec 21 '16 at 7:32

answered Dec 21 '16 at 7:21

shmoselshmosel

37.2k43997

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Is there any ready-to-use library in Java 7? My application is using Java 7, hence the code provided above is not working. Sorry for never mentioning the Java version.
  
  – user1841495
  Dec 21 '16 at 7:29
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @user1841495 Added a Java 7 version.
  
  – shmosel
  Dec 21 '16 at 7:33
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks for the solution for Java 7, do you mind to make some explanation? I'm going to test with this solution shortly. Thanks a lot.
  
  – user1841495
  Dec 21 '16 at 10:19
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @user1841495 Basically we're converting the IP address to 4 unsigned bytes, then counting the inverted bits (because this is a wildcard mask).
  
  – shmosel
  Dec 21 '16 at 18:09
  

  
  
  
  

add a comment | 

With Guava:

int slash = Integer.bitCount(
 ~Ints.fromByteArray(
 InetAddresses.forString("0.0.0.255").getAddress()));

With Java 8:

int slash = Arrays.stream("0.0.0.255".split("\."))
 .mapToInt(Integer::parseInt)
 .map(i -> ~i & 0xFF)
 .map(Integer::bitCount)
 .sum();

With Java 7:

int slash = 0;
for (String octet : "0.0.0.255".split("\.")) 
 slash += Integer.bitCount(~Integer.parseInt(octet) & 0xFF);

The value of slash will be 24.

share|improve this answer

edited Dec 21 '16 at 7:32

answered Dec 21 '16 at 7:21

shmoselshmosel

37.2k43997

int slash = Integer.bitCount(
 ~Ints.fromByteArray(
 InetAddresses.forString("0.0.0.255").getAddress()));

int slash = Arrays.stream("0.0.0.255".split("\."))
 .mapToInt(Integer::parseInt)
 .map(i -> ~i & 0xFF)
 .map(Integer::bitCount)
 .sum();

int slash = 0;
for (String octet : "0.0.0.255".split("\.")) 
 slash += Integer.bitCount(~Integer.parseInt(octet) & 0xFF);

share|improve this answer

edited Dec 21 '16 at 7:32

answered Dec 21 '16 at 7:21

shmoselshmosel

37.2k43997

answered Dec 21 '16 at 7:21

shmoselshmosel

37.2k43997

answered Dec 21 '16 at 7:21

shmoselshmosel

37.2k43997

0

The IPAddress Java library supports both IPv4 and IPv6 subnets in a polymorphic manner. Disclaimer: I am the project manager. The following code will convert a host mask to a prefix length:

IPAddressString maskString = new IPAddressString("0.0.0.255");
IPAddress mask = maskString.toAddress();
Integer prefLen = mask.getBlockMaskPrefixLength(false);//24

share|improve this answer

answered Mar 22 at 22:17

Sean FSean F

2,096614

add a comment | 

0

The IPAddress Java library supports both IPv4 and IPv6 subnets in a polymorphic manner. Disclaimer: I am the project manager. The following code will convert a host mask to a prefix length:

IPAddressString maskString = new IPAddressString("0.0.0.255");
IPAddress mask = maskString.toAddress();
Integer prefLen = mask.getBlockMaskPrefixLength(false);//24

share|improve this answer

answered Mar 22 at 22:17

Sean FSean F

2,096614

add a comment | 

The IPAddress Java library supports both IPv4 and IPv6 subnets in a polymorphic manner. Disclaimer: I am the project manager. The following code will convert a host mask to a prefix length:

IPAddressString maskString = new IPAddressString("0.0.0.255");
IPAddress mask = maskString.toAddress();
Integer prefLen = mask.getBlockMaskPrefixLength(false);//24

share|improve this answer

answered Mar 22 at 22:17

Sean FSean F

2,096614

IPAddressString maskString = new IPAddressString("0.0.0.255");
IPAddress mask = maskString.toAddress();
Integer prefLen = mask.getBlockMaskPrefixLength(false);//24

share|improve this answer

answered Mar 22 at 22:17

Sean FSean F

2,096614

answered Mar 22 at 22:17

Sean FSean F

2,096614

answered Mar 22 at 22:17

Sean FSean F

2,096614