String s = "Mahendra" + "Singh" + "Dhoni";

String s = "Mahendra";
s = s + "Singh" + "Dhoni";

String s = "Singh";
s = "Mahendra" + s + "Dhoni";

public static void main(String[] args) {
    String s = "Mahendra" + "Singh" + "Dhoni";
    System.out.println(s);
}

public static void main(java.lang.String[]);
   descriptor: ([Ljava/lang/String;)V
   flags: ACC_PUBLIC, ACC_STATIC
   Code:
     stack=2, locals=2, args_size=1
        0: ldc           #16                 // String MahendraSinghDhoni --> This line
        2: astore_1
        3: getstatic     #18                 // Field java/lang/System.out:Ljav
/io/PrintStream;
        6: aload_1
        7: invokevirtual #24                 // Method java/io/PrintStream.prin
ln:(Ljava/lang/String;)V
       10: return

String concatenation = "a" + "b" + "c";

String concatenation = "abc";

String a;
String b;
String c;
String d;
String e;

// Initialization and use of a, b, c, d, e
String concat = a + b + c + d + e;

String a;
String b;
String c;
String d;
String e;

// Initialization and use of a, b, c, d, e

String concat = new StringBuilder(a).append(b).append(c).append(d).append(e).toString();

String a;
String b;
String c;


// Initialization and use of a, b, c
String concat = a + b + c;

String a;
String b;
String c;


// Initialization and use of a, b, c
String concat = a.concat(b).concat(c);

public String concat(String str) {
    int otherLen = str.length();
    if (otherLen == 0) {
        return this;
    }
    char buf[] = new char[count + otherLen];
    getChars(0, count, buf, 0);
    str.getChars(0, otherLen, buf, count);
    return new String(0, count + otherLen, buf);
}