output should be string matched but it didn't

Question

public class reverse_string { public static void main(String[] args) {

    StringBuffer s1 =  new StringBuffer("madam");
    System.out.print(s1);
    StringBuffer s2 = new StringBuffer(s1.reverse());
    System.out.print("\n"+s2);


    if(s1.equals(s2))
    {
        System.out.print("\nreal string and reverse string are matched");
    }
    else
    {
        System.out.print("\nreal string and reverse string are not matched");
    }

} }

Where does `javascript` and `arrays` and `swing` come in to play here? — achAmháin, Dec 13 '17 at 11:07
Check this https://stackoverflow.com/questions/2012305/comparing-stringbuffer-content-with-equals — Ramesh sambu, Dec 13 '17 at 11:08

score 0 · Answer 1 · answered Dec 13 '17 at 11:05

StringBuffer will do a reference comparison with equals. Since they are not the same object, the comparison returns false.

change your code to

s1.toString().equals(s2.toString())

this will compare the values of the Strings.

Also: JavaScript and Java are not the same thing.

score 0 · Accepted Answer · answered Dec 13 '17 at 11:09

0

You are comparing two StringBuffer instantes, not the strings itself.

Try adding .toString() to convert them to a String.

answered Dec 13 '17 at 11:09

tiagodws

1,345
13
20

score 0 · Answer 3 · answered Dec 13 '17 at 11:10

0

StringBuffer doesn't override equals() from String, its equals() method is the one inherited from java.lang.Object, which returns true if and only if "==" would be true. That is, it compares the references of the two objects, which are not equal.

answered Dec 13 '17 at 11:10

Shiksha Verma

130
9

output should be string matched but it didn't

3 Answers3