This question already has answers here:
when should I override Equals function? [duplicate]
(3 answers)
Closed 2 years ago.
Why Equals() method override in Java.Reasons for it?
I was not able to understand it clearly.
The java string equals() method compares the two given strings based on the content of the string. If any character is not matched, it returns false. If all characters are matched, it returns true.Whereas (==) compares the references.
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This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 4 years ago.
I'm trying to run code based off of a cell being pulled in from my excel sheet. My code runs but then it stops at the if statement. If statement below.
if(data03 == "Checkpoint")
java
Try :-
if ("Checkpoint".equals(data03)) { }
For String comparisons .equals() function is used in java. Not ==. The == just compares object references. .equals() tests for equality.
For more Information.
This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 5 years ago.
I am encountering a weird problem. I was trying to compare two 128 bits strings and I believe every char of them match each other(and I tested comparing String.chartAt(#) several times) but when I do
if (String 1== String 2)
..
else
..
It went to else clause. Why is that?
When using == for comparison, you are checking if both variables refer to the same object (reference comparision). You should use strings equals() method in order to compare if they are equal in a sense they consist of same characters.
description of equals method in java documentation
public boolean equals(Object anObject)
Compares this string to the specified object. The result is true if
and only if the argument is not null and is a String object that
represents the same sequence of characters as this object.
This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 8 years ago.
String a ="abc";
return (a.substring(1)=="bc");
I tried to print the result of
a.substring(1)
which is also
"bc"
Why the result is false?
I think it's true.
== compares references and the value of primitives (int, long etc), use a.substring(1).equals("bc") instead.
It should be like this:
String s = "abc";
System.out.println(s.substring(1).equals("bc"));
This question already has answers here:
Comparing strings with == which are declared final in Java
(6 answers)
Closed 9 years ago.
while comparing to strings we can do using == or .equals()
In == we know that it checks for references but in .equals() it checks for contents.
So suppose if there are 2 strings say
String s="SO";
String s1="SO";
so in this case s1==s and s.equals(s1) both will give true.
But here it gives me false
So what I assume is + is high priority than ==
so in this case
System.out.println(""+s1==s);
it will be splitted like (""+s1)==s and now ""+s1 will be a new String and hence the new String will never be equal to s so its printing false
I am just interested to know whether I thought is right or not
""+s1 creates a new String Object on the heap (since it is not declared as final). So, the references will not be same.
This question already has answers here:
How do I compare strings in Java?
(23 answers)
Difference in string comparison result b/w == and String#replace with == [duplicate]
(6 answers)
Closed 9 years ago.
System.out.print("a".replace('a','1')=="a".replace('a','1'));
true was expected as replace() returns String and String comparison is possible with ==.
But the above code prints false. Explanations?
== checks if they are the same object in memory, so at the same location.
Since these are two distinct strings that just happen to have the same content you need to compare with .equals which compares values not reference.
No, string comparison is not advisable with ==. In certain cases e.g.:
new String("test") == new String("test")
it returns false.
All this is because theoretically Java should search for certain string in string pool, but in practice there are operations that returns new object instead of the one that resides in string pool.
This is very important to always use "equals" method instead of ==!!