Java programming

4) class Teststring public void stringReplace (String text) text = text.replace(.j' text-text+"C"; 'i'); , public void bufferReplace (StringBuffer text) t text.setCharAt (0,'i') text text.append("C"); public void change(char ch[l) ch[0]- 'Y' public static void main(String args[) String str1-"java" StringBuffer str2 new StringBuffer("java"); char chl]-('j','a,'v','a'; Teststring t-new TestString) t.change(ch); t.stringReplace (str1): t.bufferReplace (str2); System.out.println(str1); System.out.println(str2.toString()) System.out.print1n (new String(ch))