how to remove string from string code example

Example 1: how to remove letters from string

public extractLetters(String str){
	String result="";
	for(int i= 0; i< str.length; i++){
	    if(Character.isLetter(str.charAt(i))){
	    result+=str.charAt(i);
	  	}
	}

Example 2: remove part of string java

// Works only if you have a certain character at which you want to cut
String text = "Image.png";

String[] cutText = text.split("\\.");

// cutText[0] has value "Image"
// cutText[1] has value "png"