3.10.6

Escape Sequences for Character and String Literals

LEXICAL STRUCTURE

Thus, the test program consisting of the compilation unit ( 7.3):

package testPackage;

class Test {

public static void main(String[] args) {

String hello = "Hello", lo = "lo";

System.out.print((hello == "Hello") + " ");

System.out.print((Other.hello == hello) + " ");

System.out.print((other.Other.hello == hello) + " ");

System.out.print((hello == ("Hel"+"lo")) + " ");

System.out.print((hello == ("Hel"+lo)) + " ");

System.out.println(hello == ("Hel"+lo).intern());

}

}

class Other { static String hello = "Hello"; }

and the compilation unit:

package other;

public class Other { static String hello = "Hello"; }

produces the output:

true true true true false true

This example illustrates six points:

Literal strings within the same class ( 8) in the same package ( 7) represent

references to the same

String

 object ( 4.3.1).

Literal strings within different classes in the same package represent refer 

ences to the same

String

 object.

Literal strings within different classes in different packages likewise represent

references to the same

String

 object.

Strings computed by constant expressions ( 15.27) are computed at compile

time and then treated as if they were literals.

Strings computed at run time are newly created and therefore distinct.

The result of explicitly interning a computed string is the same string as any

pre existing literal string with the same contents.

3.10.6   Escape Sequences for Character and String Literals

The character and string

escape sequences

 allow for the representation of some

nongraphic characters as well as the single quote, double quote, and backslash

characters in character literals ( 3.10.4) and string literals ( 3.10.5).

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