[Q#9108781][A#9108806] How to remove leading and trailing whitespace from the string in Java?

I want to remove the leading and trailing whitespace from string: I want the result to be like:

Answer

see String#trim() Without any internal method, use regex like or or just use pattern in pure form

APIzation

s.trim()
s.replaceAll("^\\s+", "").replaceAll("\\s+$", "")
s.replaceAll("^\\s+|\\s+$", "")
String s="          Hello World                    ";
    Pattern trimmer = Pattern.compile("^\\s+|\\s+$");
    Matcher m = trimmer.matcher(s);
    StringBuffer out = new StringBuffer();
    while(m.find())
        m.appendReplacement(out, "");
    m.appendTail(out);
    System.out.println(out+"!");

package com.stackoverflow.api;

public class Human9108806 {

  public static String removeLeadingAndTrailingWhitespaces(String s) {
    return s.replaceAll("^\\s+", "").replaceAll("\\s+$", "");
  }
}

package com.stackoverflow.api;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * How to remove leading and trailing whitespace from the string in Java?
 *
 * @author APIzator
 * @see <a href="https://stackoverflow.com/a/9108806">https://stackoverflow.com/a/9108806</a>
 */
public class APIzator9108806 {

  public static String remove(String s) throws Exception {
    Pattern trimmer = Pattern.compile("^\\s+|\\s+$");
    Matcher m = trimmer.matcher(s);
    StringBuffer out = new StringBuffer();
    while (m.find()) m.appendReplacement(out, "");
    m.appendTail(out);
    return out + "!";
  }
}