Why do I get an OutOfMemory error?

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I get the following exception when trying to run my program: Exception in thread "main" java.lang.OutOfMemoryError: Java heap space at java.util.Arrays.copyOf(Arrays.java:3210) at java.util.Arrays.copyOf(Arrays.java:3181) at java.util.ArrayList.grow(ArrayList.java:265) at java.util.ArrayList.ensureExplicitCapacity(ArrayList.java:239) at java.util.ArrayList.ensureCapacityInternal(ArrayList.java:231) at java.util.ArrayList.add(ArrayList.java:479) at com.codegym.task.task07.task0717.Solution.doubleValues(Solution.java:33) at com.codegym.task.task07.task0717.Solution.main(Solution.java:23) After some googling I learned that this has something to do with the Garbage Collector not being able to delete object and thus the program running out of memory. But how can that happen with such a small program? Is there something wrong with my code?

1. Create a list of words and populate it yourself.
2. The fix method should:
2.1. remove all words containing the letter "r" from the list
2.2. duplicate all words containing the letter "l".
2.3. if a word contains both "r" and "l", then leave it unchanged.
2.4. don't do anything to other words.

For example:
rose lyre love

Output:
lyre love love

Requirements:

The program must not read data from the keyboard.
The fix method should remove all words containing the letter "r" from the list. There is an exception: words containing both "r" and "l" should be left alone.
The fix method must duplicate words containing the letter "l" (add another instance of this word to the list). There is an exception: words containing both "l" and "r" should not be duplicated.
The fix method should not do anything with words that contain both "l" and "r".
The fix method should not do anything with words that don't contain either "l" or "r".

package com.codegym.task.task07.task0716; import java.util.ArrayList; /* R or L */ public class Solution { public static void main(String[] args) throws Exception { ArrayList<String> list = new ArrayList<String>(); list.add("rose"); // 0 list.add("lyre"); // 1 list.add("love"); // 2 list = fix(list); for (String s : list) { System.out.println(s); } } public static ArrayList<String> fix(ArrayList<String> list) { for (int i = 0; i < list.size(); i++) { String string = list.get(i); if((string.indexOf('r')>=0)&&(string.indexOf('l')<0)) list.remove(i); else if ((string.indexOf('l')>=0)&&(string.indexOf('r')<0)) list.add(i+1, string); } return list; } }

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Ellen

Level 29 , Antwerpen, Belgium

1 December 2019, 11:16

Great, thank you! I saw my mistake and was able to fix it.

Guadalupe Gagnon

Level 37 , Tampa, United States

1 December 2019, 03:38

solution

You have an infinite loop. Modify (copy and paste) your code to this:

public class Solution {
    public static void main(String[] args) throws Exception {
        ArrayList<String> list = new ArrayList<String>();
        list.add("rose"); // 0
        list.add("lyre"); // 1
        list.add("love"); // 2
        list = fix(list);

        for (String s : list) {
            System.out.println(s);
        }
    }

    public static ArrayList<String> fix(ArrayList<String> list) {
        for (int i = 0; i < list.size(); i++) {
            String string = list.get(i);
            System.out.println("Testing " + string);
            if((string.indexOf('r')>=0)&&(string.indexOf('l')<0)) {
                System.out.println("\tremoving");
                list.remove(i);
            }
            else if ((string.indexOf('l')>=0)&&(string.indexOf('r')<0)) {
                System.out.println("\tadding");
                list.add(i + 1, string);
            }
            System.out.println("\t" + list);
            try {
                Thread.sleep(200);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        return list;
    }
}

And run it in intelliJ or eclipse. If you don't have one, then go get one. With this coe you can see what is going on with your code.