Java program to concatenate the given strings using concat() method
GD.java
class GD
{
    public static void main(String args[])
    {
        String s="HELLO";
        s=s.concat(" WORLD");
        System.out.println(s);
    }
}
Output
godarda@gd:~$ javac GD.java
godarda@gd:~$ java GD
HELLO WORLD
godarda@gd:~$
Java program to concatenate the given strings by passing object as a value
GD.java
class GD
{
    public static void main(String args[])
    {
        String s1="HELLO";
        String s2="WORLD";
        System.out.println(s1+s2);
    }
}
Output
godarda@gd:~$ javac GD.java
godarda@gd:~$ java GD
HELLO WORLD
godarda@gd:~$
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