contract « hashcode « Java Class Q&A

1.	abstract class
2.	Base class
3.	class hierarchy
4.	class name
5.	class version
6.	Class.forName
7.	ClassCastException
8.	Clone
9.	constant
10.	Constructor
11.	Development
12.	DTO
13.	encapsulation
14.	equal method
15.	extend Class
16.	getter
17.	hashcode
18.	Inheritance
19.	inner class
20.	interface
21.	main class
22.	Method
23.	NoClassDefFoundError
24.	NoSuchMethodError
25.	NoSuchMethodException
26.	object reference
27.	overload
28.	parent class
29.	Polymorphism
30.	private
31.	Private Field
32.	Recursive
33.	setter
34.	Static
35.	Static Class
36.	subclass
37.	Super
38.	toString
39.	Wrapper Class

Java Class Q&A » hashcode » contract

1. equals() and hashCode() contract in Java stackoverflow.com

The SCJP 6 Study Guide from Bert Bates and Kathy Sierra states on page 554 (among other requirements) that x.hashCode() != y.hashCode() requires that x.equals(y) == false. But the Javadoc for Object ...

2. equals and hashcode - Justify Contract stackoverflow.com

If two objects are equal then they should have the same hascode but the reverse is not true (i.e. If two objects have the same hashcode does not mean that they ...

3. Hashcode contract in java? stackoverflow.com

Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no ...

4. what is contract between equal and hash code coderanch.com

5. hashCode() contract java-forums.org

class HashCodeTest1 { int x; int y; HashCodeTest1(int x, int y) { this.x = x; this.y = y; } public boolean equals(Object o) { if (this.x == ((HashCodeTest1)o).x) return true; return false; } public int hashCode() { return y; } public static void main(String ... args) { HashCodeTest1 obj1 = new HashCodeTest1(10,10); HashCodeTest1 obj2 = new HashCodeTest1(10,20); System.out.println(obj1.equals(obj2)); System.out.println(obj1.hashCode() == obj2.hashCode()); ...

6. the hashCode() contract java-forums.org

according to my scjp book (Exam 310-065) there are no hashCode requirements when x.equals(y) otherwise I would have a problem for a class Person that has a field name as String. Instantiating two Persons with new Person("May") and new Person("Amy") equals() returns true, but for me equals() should return false, since May and Amy are not the same. I override equals() ...

7. equals and hashCode contract forums.oracle.com

Hi All, I want to why it is mention that whenever a class override equals method it must also override hashCode method? Even any program which only override either of tow compile and runs successfully. I try to debug the code and find that no where equals method relegate the call to hasCode method. So why this contact exist in java? ...