Java – Text area text to be split with conditions

javasplitstring

I have a text area where a user can enter free flow text. I want to separate out lines/occurrences in my Java class based on the below conditions:

When the user does not press the enter key, I want to get substrings (texts) of 10 characters each. When the user does press enter, I want to separate that part out and start again counting till 15 to get a new substring till I reach the end of the free flow text/string.

Eg,
If user enters:

Hello I want
enter key to be caught.

I want this text to be separated into the below substrings:

Hello I want (assuming the user pressed enter key at this point)
enter key to be (as the limit is 15)
caught

Best Solution

if( text.contains("\n") ) {

  counter = 15;
  String[] splitText = text.split("\n");
  ArrayList<String> chunks - new ArrayList<String>(text.length%counter+1);
  StringBuilder current = new StringBuilder(counter);

  for( int i = 0; i < splitText.length; i++ ) {
    for( int j = 0; j < splitText[i].length; j++ ) {
      current.append(text.charAt(j));
      if( j%15 == 0 ) {
        chunks.add(current.toString());
        current = new StringBuilder(counter);
      }
    }
    chunks.add(current.toString());
    current = new StringBuilder(counter);
  }

}

With that you can figure out the other requirement you had. It's basically the same just not with 15 or nested loops.

Related Solutions

Java – How to split a string with any whitespace chars as delimiters

Something in the lines of

myString.split("\\s+");

This groups all white spaces as a delimiter.

So if I have the string:

"Hello[space character][tab character]World"

This should yield the strings "Hello" and "World" and omit the empty space between the [space] and the [tab].

As VonC pointed out, the backslash should be escaped, because Java would first try to escape the string to a special character, and send that to be parsed. What you want, is the literal "\s", which means, you need to pass "\\s". It can get a bit confusing.

The \\s is equivalent to [ \\t\\n\\x0B\\f\\r].

Python – How to split a list into evenly sized chunks

Here's a generator that yields the chunks you want:

def chunks(lst, n):
    """Yield successive n-sized chunks from lst."""
    for i in range(0, len(lst), n):
        yield lst[i:i + n]

import pprint
pprint.pprint(list(chunks(range(10, 75), 10)))
[[10, 11, 12, 13, 14, 15, 16, 17, 18, 19],
 [20, 21, 22, 23, 24, 25, 26, 27, 28, 29],
 [30, 31, 32, 33, 34, 35, 36, 37, 38, 39],
 [40, 41, 42, 43, 44, 45, 46, 47, 48, 49],
 [50, 51, 52, 53, 54, 55, 56, 57, 58, 59],
 [60, 61, 62, 63, 64, 65, 66, 67, 68, 69],
 [70, 71, 72, 73, 74]]

If you're using Python 2, you should use xrange() instead of range():

def chunks(lst, n):
    """Yield successive n-sized chunks from lst."""
    for i in xrange(0, len(lst), n):
        yield lst[i:i + n]

Also you can simply use list comprehension instead of writing a function, though it's a good idea to encapsulate operations like this in named functions so that your code is easier to understand. Python 3:

[lst[i:i + n] for i in range(0, len(lst), n)]

Python 2 version:

[lst[i:i + n] for i in xrange(0, len(lst), n)]

Best Solution

Related Solutions

Java – How to split a string with any whitespace chars as delimiters

Python – How to split a list into evenly sized chunks

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