what is this "blabla" from Java point of view?

Question

I am wondering if

String s = new String("blabla");

is exactly the same as

String s = "blabla";

I think for the first one this constructor of the String class is called:

 public String(char value[]) {
        this.value = Arrays.copyOf(value, value.length);
    }

but not sure if it's the same for the second one.

In other words, what is this "blabla" from Java point of view?

So while using String s = "blabla"; is s a new stance of String class? and if yes which of its constructors is called?

"I think for the first one this constructor of the String class is called:" no. `"blabla"` is a string literal, which is a `String`, not a `char[]`. This constructor is not the one called. — Andy Turner, Mar 12 '17 at 20:40
@AndyTurner so probably this shoud be the one: `public String(String original) { this.value = original.value; this.hash = original.hash; }` — farmcommand2, Mar 12 '17 at 20:46
yes, a constructor has to be called at some point; it's just not called where it appears in the code, unlike with `new String(...)`. — Andy Turner, Mar 12 '17 at 20:53
I've never cared enough to check which constructor is called; but it's going to be called when the class is loaded. — Andy Turner, Mar 12 '17 at 21:22

score 0 · Accepted Answer · answered Mar 12 '17 at 20:39

0

Actually as you may already know String is an immutable class which means once it's intialized it can't be changed anymore so this is exactly why there is two why of creating Strings.

String s = "blabla" : Here this String is created and pushed to the String Constant Pool if it's not already exist.
String s = new String("blabla") : However like this a new String is created each time, without checking if it's already exist in the Pool.

Note : that String s = new String("blabla").intern() is equivalent to String s = "blabla" .

answered Mar 12 '17 at 20:39

Mouad EL Fakir

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so if there is nothing in the pool (there are no string created yet) then `String s = "blabla"` creates a new instance? and if so, what is the called constructor? – farmcommand2 Mar 12 '17 at 20:49
The constructor being called in this case is `public String(char value[])` to make sure put a break point at this constructor and run the debug mode. – Mouad EL Fakir Mar 12 '17 at 21:03

what is this "blabla" from Java point of view?

1 Answers1