gistfile1.html

Using Java, with no help from 3rd party libraries, there is the old way and the new way. Just sorting used to be easy with Collections.sort(..).

The challenge with the old way was that a lot of code was required to group the values.

 - Input: List<String>
 - Output: Map<Character,<List<String>>
 - The key of map is 'A' to 'Z'
 - Each list in the map are sorted.
Old Java

List<String> keywords = Arrays.asList("Apple", "Ananas", "Mango", "Banana", "Beer"); 
Map<Character, List<String>> result = new HashMap<Character, List<String>>(); 
for(String k : keywords) {   
    char firstChar = k.charAt(0);     
    if(!result.containsKey(firstChar)) {     
        result.put(firstChar, new  ArrayList<String>());   
    }     
    result.get(firstChar).add(k); 
} 
for(List<String> list : result.values()) {   
    Collections.sort(list); 
}
System.out.println(result); 
New Java 8

List<String> keywords = Arrays.asList("Apple", "Ananas", "Mango", "Banana", "Beer");
Map<Character, List<String>> result = keywords.stream().sorted()
        .collect(Collectors.groupingBy(it -> it.charAt(0)));
System.out.println(result);