线程“main”java中出现异常。lang.OutOfMemoryError:使用util包时的Java堆空间

我的问题陈述:

一个文件中将有一组给定的单词(>5000个单词)。我们需要返回每个字符串(一组字谜)中由逗号(,)分隔的字谜列表 例如:[改变,稍后,分开,陷阱,肘部,下面,听,沉默,紧张]

例外情况:

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:462)
at FindAnagrams01.anagramsList(FindAnagrams01.java:25)
at FindAnagrams01.main(FindAnagrams01.java:7)

我的代码是:

  public static List<String> anagramsList(String filePath) throws IOException {
    BufferedReader br = new BufferedReader(new FileReader(filePath));
    String str = br.readLine();
    List<List<String>> result = new ArrayList<List<String>>(10000);
    HashMap<String, ArrayList<String>> map = new HashMap<String,ArrayList<String>>(10000);
    while(str != null) {
        char[] arr = new char[26];
        for(int i = 0; i < str.length(); i++) {
            arr[str.charAt(i) - 'a']++;              
        }
        String ns = new String(arr);
        if(map.containsKey(ns)){
            map.get(ns).add(str);
        } else {
            ArrayList<String> al = new ArrayList<String>(10000);
            al.add(str);
            map.put(ns, al);
        }
    }
    br.close();
    result.addAll(map.values());
    String res[] = new String[10000];
    for(int i = 0; i < result.size(); i++) {
        int isIntial = 0;
        for(String j : result.get(i)) {
            if ((result.get(i).size()) > 1) {
                if (isIntial == 0) {
                    res[i] = j;
                    isIntial = 1;
                }
                else
                    res[i] += "," + j;
            } 
        }
    }
    List<String> angrms = new ArrayList<String>(10000);
    for (int i = 0; i < res.length; i++) {
        if (res[i] != null)
            angrms.add(res[i]);
    }
    return angrms;
}