Java - Write code to Return an ArrayList of strings, one for each line in the string. This code assumes str is not null.

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Requirements

Write code to Return an ArrayList of strings, one for each line in the string. This code assumes str is not null.

Demo

//package com.book2s;

import java.util.*;

public class Main {
    public static void main(String[] argv) {
        String str = "boo\n\n\n\nk2\r\r\r\ns.com";
        System.out.println(splitIntoLines(str));
    }//from w w w.  j  ava2 s  .c o  m

    /**
     * Returns an ArrayList of strings, one for each line in the string.<br><br>
     * This code assumes <var>str</var> is not <code>null</code>.
     * @param str The string to split
     * @return A non-empty list of strings
     */
    public static List<String> splitIntoLines(String str) {
        ArrayList<String> strings = new ArrayList<String>();

        int len = str.length();
        if (len == 0) {
            strings.add("");
            return strings;
        }

        int lineStart = 0;

        for (int i = 0; i < len; ++i) {
            char c = str.charAt(i);
            if (c == '\r') {
                int newlineLength = 1;
                if ((i + 1) < len && str.charAt(i + 1) == '\n')
                    newlineLength = 2;
                strings.add(str.substring(lineStart, i));
                lineStart = i + newlineLength;
                if (newlineLength == 2) // skip \n next time through loop
                    ++i;
            } else if (c == '\n') {
                strings.add(str.substring(lineStart, i));
                lineStart = i + 1;
            }
        }
        if (lineStart < len)
            strings.add(str.substring(lineStart));

        return strings;
    }
}

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