A few additional comments to complement the other review:
Avoid spelling errors, especially in user-visible strings
The first error message has "octect" but what was meant was undoubtedly "octet". Spelling errors in code are unfortunately relatively common, but we should all make special effort to avoid such errors in user-visible strings. It could lead a user of the code to wonder how many less visible errors are also in the code.
Convert variables only when required
The ip variable is already a String, so ip.getText().toString()) seems to be doubly redundant.
Consider other error conditions
Some addresses will pass this validation but may, depending on context, not be appropriate. Two such addresses are 0.0.0.0 and 255.255.255.255 (Broadcast address). Other special addresses might also be inappropriate, depending on context. It may be useful to augment the existing code with additional functions which check for usability within a given context.
Be aware of exceptions that may be thrown
The StringUtils.isNumeric(octet) call will return true with an empty string return true with an empty string, but Integer.parseInt(octet) will throw a NumberFormatException. You may want to handle that in case the passed string is something like "0.0..0".
A few additional comments to complement the other review:
Avoid spelling errors, especially in user-visible strings
The first error message has "octect" but what was meant was undoubtedly "octet". Spelling errors in code are unfortunately relatively common, but we should all make special effort to avoid such errors in user-visible strings. It could lead a user of the code to wonder how many less visible errors are also in the code.
Convert variables only when required
The ip variable is already a String, so ip.getText().toString()) seems to be doubly redundant.
Consider other error conditions
Some addresses will pass this validation but may, depending on context, not be appropriate. Two such addresses are 0.0.0.0 and 255.255.255.255 (Broadcast address). Other special addresses might also be inappropriate, depending on context. It may be useful to augment the existing code with additional functions which check for usability within a given context.
Be aware of exceptions that may be thrown
The StringUtils.isNumeric(octet) call will return true with an empty string, but Integer.parseInt(octet) will throw a NumberFormatException. You may want to handle that in case the passed string is something like "0.0..0".
A few additional comments to complement the other review:
Avoid spelling errors, especially in user-visible strings
The first error message has "octect" but what was meant was undoubtedly "octet". Spelling errors in code are unfortunately relatively common, but we should all make special effort to avoid such errors in user-visible strings. It could lead a user of the code to wonder how many less visible errors are also in the code.
Convert variables only when required
The ip variable is already a String, so ip.getText().toString()) seems to be doubly redundant.
Consider other error conditions
Some addresses will pass this validation but may, depending on context, not be appropriate. Two such addresses are 0.0.0.0 and 255.255.255.255 (Broadcast address). Other special addresses might also be inappropriate, depending on context. It may be useful to augment the existing code with additional functions which check for usability within a given context.
Be aware of exceptions that may be thrown
The StringUtils.isNumeric(octet) call will return true with an empty string, but Integer.parseInt(octet) will throw a NumberFormatException. You may want to handle that in case the passed string is something like "0.0..0".
A few additional comments to complement the other review:
Avoid spelling errors, especially in user-visible strings
The first error message has "octect" but what was meant was undoubtedly "octet". Spelling errors in code are unfortunately relatively common, but we should all make special effort to avoid such errors in user-visible strings. It could lead a user of the code to wonder how many less visible errors are also in the code.
Convert variables only when required
The ip variable is already a String, so ip.getText().toString()) seems to be doubly redundant.
Consider other error conditions
Some addresses will pass this validation but may, depending on context, not be appropriate. Two such addresses are 0.0.0.0 and 255.255.255.255 (Broadcast address). Other special addresses might also be inappropriate, depending on context. It may be useful to augment the existing code with additional functions which check for usability within a given context.
Be aware of exceptions that may be thrown
The StringUtils.isNumeric(octet) call will return true with an empty string, but Integer.parseInt(octet) will throw a NumberFormatException. You may want to handle that in case the passed string is something like "0.0..0".