String objects with the same string pointing to the same place but?

Question

Hi,
Here is a simple sample
String str1 = "a";
String str2 = "a";I understand that in Java str1 and str2 pointing to the same place in memory and Java compiler wouldn't save the string "a" in two different places in memory. Am I right?
If so, if the value of str1 changes to something else as following:
String str1 = "a";
String str2 = "a";
str1 = "b";why str2 which has been pointing to the same place as str1 before is still containing ?a? and not ?b????
Thanks!

Answer 1

Maria1990 wrote:
Hi,
Here is a simple sample
String str1 = "a";
String str2 = "a";I understand that in Java str1 and str2 pointing to the same place in memory and Java compiler wouldn't save the string "a" in two different places in memory. Am I right?Correct.
Maria1990 wrote:
If so, if the value of str1 changes to something else as following:
String str1 = "a";
String str2 = "a";
str1 = "b";why str2 which has been pointing to the same place as str1 before is still containing ?a? and not ?b????Because str2 is pointing to the same "a", but it is not pointing to str1.
This is what happens:
String str1 = "a";
/*                 +---+
         str1 ---->| a |
                   +---+
String str2 = "a";
/*                 +---+
         str1 --+->| a |
                |  +---+
                |
         str2 --+
NOT:
                   +---+
     +-> str1 ---->| a |
     |             +---+
     |
     +- str2
str1 = "b";
                   +---+
             +---->| b |
             |     +---+
             |
             |     +---+
        str1-+  +->| a |
                |  +---+
                |
         str2 --+
*/