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String - najczęściej używane metody

Substring
  • public String substring(int startIndex) 
  • public String substring(int startIndex, int endIndex)

String s= "Hello World";
System.out.println(s.substring(3));
System.out.println(s.substring(1,3));

StringBuffer - creates mutable string. String is originally immutable. Used operation on Strings



        StringBuffer buffer = new StringBuffer("Hello World");
        buffer.append(" GREAT ADDITION");
        System.out.println(buffer);

StringBuilder - more efficient than StringBuffor
https://www.javatpoint.com/StringBuilder-class



  • charAt() - returns char on defined index
  • contains() - true false
  • endsWith()  startsWith() - 
  • indexOf() - returns index of char
  • isEmpty() - true false
  • length() - 
  • replace() - replace char 
  • split()
  • trim() - 
  • toLowerCase() i toUpperCase

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