Java Basic - KelasString part 4

/**
 *
 * @author ardie
 */
public class KelasString4 {

    public static void main(String[] args) {
        char[] ch = {'g', 'o', 'o', 'd', ' ', 'm', 'o', 'r', 'n', 'i', 'n', 'g'};
        String str = new String(ch);
        System.out.println(str); // char to string 

        // konversi char ke string 
        char[] kata = {'s', 'e', 'l', 'a', 'm', 'a', 't'};
        String str2 = String.valueOf(kata);
        System.out.println(str2);

        String str3 = "studytonight";
        String str4 = "java";
        String str5 = "Count me";
        String str6 = "Change me";
        String str7 = "0123456789";
        String str8 = "ABCDEF";
        String str9 = "Ardiansyah";

        System.out.println(str3.charAt(2));
        System.out.println(str4.equalsIgnoreCase("JAVA"));
        System.out.println(str5.length());
        System.out.println(str6.replace('e', 'E'));
        System.out.println(str6.substring(4));
        System.out.println(str7.substring(4, 7));
        System.out.println(str8.toLowerCase());
        System.out.println(str9.toUpperCase());
    }
}
// valueOf() digunakan untuk convert primitive data type into String
// but objects, valueOf() method calls toString() function
// for example like this
class Car {

    public String toString() {
        return "This is my car object";
    }
}

Output :
good morning
selamat
u
true
8
ChangE mE
ge me
456
abcdef
ARDIANSYAH