How to search as LIKe operator in sql in hash map in java

Question

I want to search for a hash map based on user input. Suppose the user gives the value "A", I have to show starting with the name of the company, and if the user gives the value "AB", I have to show starting with the name of the company AB. I store the company name in a hash map

Answer 1

• Use NavigableSet .

  Example:

  NavigableSet<String> company=new TreeSet<String>(); 
  Set<String> filteredSet=company.tailSet(prefix);
  for(String str:filteredSet) {
   if(str.startsWith(prefix))
    //add to list
   else
    break;
  }
  

• Use the tree [wiki] or trie [wiki] if you are interested in performance. The radix base is more efficient than trie.

Answer 2

, , .

:

• . , , .
• trie ( ), node - " " node, .

Answer 3

. :

final String searchPrefix = "AB";
for(String key : map.keySet()){
    if(key.startsWith(searchPrefix)){
        System.out.println(map.get(key));
    }
}

.

final String searchPrefix = "AB";
for(Entry<String,String> e : map.entrySet()){
    if(e.getKey().startsWith(searchPrefix)){
        System.out.println(e.getValue());
    }
}

Answer 4

( )

http://download.oracle.com/javase/tutorial/essential/regex/

your company names are strings you can use

String regex = "A*";
myString.matches(regex);