java software engineer interview questions

. 28th, Programming question: Calculate 2 times 8 in the most efficient way? Programmers with a C background are particularly interested in asking such questions. 2 29th, two object values are the same (x.equals (y) = = true), but can have different hash code, this sentence is correct? No, there's the same hash code. 30th, when an object is passed as a parameter to a method, this method can change the property of the object and return the result

I. Application of the factory model in development Interview Questions:Write a simple calculator. Code implementation: Abstract An operation class: Package COM. qianyan. calcuator; public abstract class operation {// number one private double num1; // number two private double num2; Public double getnum1 () {return num1;} public void setnum1 (double num1) {This. num1 = num1;} public double getnum2 () {return num2;} public void setnum2 (double num2)

two bytes, so a char variable is also occupied by two bytes. Two Java Basics 1. Talk about polymorphic forms of expression. (1) Overloading, overriding, overloaded overload means that there can be multiple methods with the same name in the same class, but the argument lists for these methods are different (2) overriding override means that a method in a subclass can be exactly the same as the name and parameters of a method in the parent class. When

The dashed box represents the interface, the solid wireframe represents the entity class, The thick wireframe represents the most commonly used entity classes, the dashed arrows indicate the implementation of the interface, and the implementation arrows indicate that the class can make objects of the class that the arrows refer to. Collection: Allows only one object to be placed in each location. It includes a list of "holding a set of objects in a certain order", and a set that "only allo

Because I often go to the personal blog of the master Martin Fowler and occasionally find that the blog is recommending this book.At the same time, after two years of distributed system development in CB, I feel that it is time to summarize some of the cases I have learned and encountered. So I thought, you may want to verify whether our system has a major design problem while studying this book. Pattern Oriented Software Architecture volume.4 summar

. Make a resume in accordance with the Star rules;2. Different company positions need to be different, resume should be targeted, do not only prepare a resume;3. In accordance with the requirements of the job, in the project to highlight the matching skills, first through the screening of this;4. To be ready to vote resume, or your favorite company let you go to the interview, the result you did not how to prepare, was brushed, then the opportunity ma

difference between the 5.sendRedirect () and Forward () methods?The Sendredirect () method creates a new request, and the forward () method simply forwards the request to a new target. After redirection (redirect), objects that were within the scope of the previous request are invalidated because a new request is generated, and after forwarding (forwarding), objects within the scope range of the previous request can be accessed. Sendredirect () is generally considered to be slower than forward

the object passivation time through the configuration file---object How long it takes to not be passivatedUnder Meta-inf, create a context.xml that reads as follows:@Overridepublic void sessionwillpassivate (Httpsessionevent se) {System.out.println ("Being passivated ... ");}@Overridepublic void sessiondidactivate (Httpsessionevent se) {SYSTEM.OUT.PRINTLN ("Being activated ... ")；}When the specified servlet project is accessed, the "passivation" appears after the set time, and then any file und