- 1 What is equals and == in Java?
- 2 What is == in Java?
- 3 Is.equals the same as ==?
- 4 Should I use equals or == Java?
- 5 What is the Hashcode () and equals () used for?
- 6 Can we declare constructor as final?
- 7 What is difference between i ++ and ++ i in Java?
- 8 What is difference between == equals () and compareTo () method?
- 9 Is overriding possible in Java?
- 11 What is the difference between A equals B and a == b?
- 12 Why can’t we use == to compare String objects?
- 13 Why pointers are not used in Java?
- 14 Can we override private method in Java?
- 15 Why is string immutable in Java?
What is equals and == in Java?
In general, both equals() and “==” operator in Java are used to compare objects to check equality but here are some of the differences between the two: In simple words, == checks if both objects point to the same memory location whereas. equals() evaluates to the comparison of values in the objects.
What is == in Java?
In Java Strings, the == operator is used to check the reference of both the string objects and equals() method used to check the value equality of both strings. If we are assigning the equal value to another string variable, the JVM checks if the string with that value is present in the string constant pool or not.
Is.equals the same as ==?
== is a reference comparison, i.e. both objects point to the same memory location.. equals() evaluates to the comparison of values in the objects.
Should I use equals or == Java?
equals() is a method of Object class. == should be used during reference comparison. == checks if both references points to same location or not. equals() method should be used for content comparison.
What is the Hashcode () and equals () used for?
The hashcode() method returns the same hash value when called on two objects, which are equal according to the equals() method. And if the objects are unequal, it usually returns different hash values.
Can we declare constructor as final?
No Constructors can NEVER be declared as final. Your compiler will always give an error of the type “modifier final not allowed” Final, when applied to methods, means that the method cannot be overridden in a subclass. Constructors are NOT ordinary methods.
What is difference between i ++ and ++ i in Java?
++i and i++ both increment the value of i by 1 but in a different way. Increment in java is performed in two ways, 1) Post-Increment (i++): we use i++ in our statement if we want to use the current value, and then we want to increment the value of i by 1.
What is difference between == equals () and compareTo () method?
compareTo: Compares two strings lexicographically. equals: Compares this string to the specified object. compareTo compares two strings by their characters (at same index) and returns an integer (positive or negative) accordingly.
Is overriding possible in Java?
If subclass (child class) has the same method as declared in the parent class, it is known as method overriding in Java. In other words, If a subclass provides the specific implementation of the method that has been declared by one of its parent class, it is known as method overriding.
What is the difference between A equals B and a == b?
Reference Type Equals(sb2) returns true. == operator compares reference returns true when both references point to the same object and Equals() compares object by value and it will return true if the references refers object which are equivalent.
Why can’t we use == to compare String objects?
Now if you compare them with == it will return false despite the fact that the objects are exactly the same. Same goes for Strings. “==” compares Object references with each other and not their literal values. If both the variables point to same object, it will return true.
Why pointers are not used in Java?
So overall Java doesn’t have pointers (in the C/C++ sense) because it doesn’t need them for general purpose OOP programming. Furthermore, adding pointers to Java would undermine security and robustness and make the language more complex.
Can we override private method in Java?
1) In Java, inner Class is allowed to access private data members of outer class. 2) In Java, methods declared as private can never be overridden, they are in-fact bounded during compile time.
Why is string immutable in Java?
The String is immutable in Java because of the security, synchronization and concurrency, caching, and class loading. The reason of making string final is to destroy the immutability and to not allow others to extend it. The String objects are cached in the String pool, and it makes the String immutable.