String.valueOf() vs. Object.toString()

Question

In Java, is there any difference between String.valueOf(Object) and Object.toString()? Is there a specific code convention for these?

Answer 1

String.valueOf(Object) and Object.toString() are literally the same thing.

If you take a look at the implementation of String.valueOf(Object), you'll see that String.valueOf(Object) is basically just a null-safe invocation of toString() of the appropriate object:

Returns the string representation of the Object argument.

Parameters:
    obj an Object.
Returns:
    if the argument is null, then a string equal to "null"; 
    otherwise, the value of obj.toString() is returned.
See also:
    Object.toString()

public static String valueOf(Object obj) {
    return (obj == null) ? "null" : obj.toString();
}