Remove filename extension in Java

Question

(Without including any external libraries.)

What\'s the most efficient way to remove the extension of a filename in Java, without assuming anything of the f

Answer 1

Use new Remover().remove(String),

jdb@Vigor14:/tmp/stackoverflow> javac Remover.java && java Remover
folder > folder
hello.txt > hello
read.me > read
hello.bkp.txt > hello.bkp
weird..name > weird.
.hidden > .hidden

Remover.java,

import java.util.*;

public class Remover {

    public static void main(String [] args){
        Map tests = new LinkedHashMap();
        tests.put("folder", "folder");
        tests.put("hello.txt", "hello");
        tests.put("read.me", "read");
        tests.put("hello.bkp.txt", "hello.bkp");
        tests.put("weird..name", "weird.");
        tests.put(".hidden", ".hidden");

        Remover r = new Remover();
        for(String in: tests.keySet()){
            String actual = r.remove(in);
            log(in+" > " +actual);
            String expected = tests.get(in);
            if(!expected.equals(actual)){
                throw new RuntimeException();
            }
        }
    }

    private static void log(String s){
        System.out.println(s);
    }

    public String remove(String in){
        if(in == null) {
            return null;
        }
        int p = in.lastIndexOf(".");
        if(p <= 0){
            return in;
        }
        return in.substring(0, p);
    }
}