java practice exam

=======================================================The similarities and differences between Java and C + +:Same point: Java and C + + have similar syntax and control structuresDifferent points: Java has no preprocessor or file contains;No pointers, no global variables;No structures and unions;All primitive types (basic types) have a definite size;No operator

Java language Program Design midterm exam question One, programming question 1. Abstract classCreate a closed Graph abstract class (closedfigure), define an abstract method to calculate the area, create a two subclass ellipse (Ellipse) and Rectangle (Rectangle) that inherits the plane graph abstract class, and implement the method of calculating the plot area in the subclass. The design test class Test1 car

database product.(4) familiar with high concurrency, big data in the case of database development.7 Web Technology(1) Learn how Ajax works.(2) Be familiar with at least one JS framework (such as jquery).8 Design Patterns(1) familiar with the common design patterns.(2) The design pattern theory is applied to the actual development.9 Linux(1) Skilled use of common Linux commands.(2) familiar with the basic concepts and characteristics of Linux operating system.(3) familiar with shell scripts.10 O

() method.parsing:add elements to the ArrayList collection with a For loop, there is no error in the code, but the Java virtual machine gives the [], all B is correctparsing:set is an interface to the list at the same level, and there is no inheritance relationship between the two. parsing:The elements in the HashMap collection are unordered.parsing:HashMap is non-thread safe (unsynchronized), allows the key value to be null, and Hashtable is not all

12345789 - -Java Siege Lion interview exam

} } if(Flag = =true) {System.out.println (i); } } }}Three: recursive algorithm to achieve factorial Packagedemo; Public classFactorial { Public Static voidMain (string[] agrs) {System.out.println (factorial (17));//calculates the factorial of 17} Public Static LongFactorial (inti) { if(i==1){ return1; }Else{ returnI*factorial (i-1);//Recursive Run }}}Four: The title: A ball from 100 meters height of freedom falling, each landing

, coursename from enrollment"; Class.forName (driver_name); Try{conn=drivermanager.getconnection (URL, user_name, PASSWORD); Ptmt=conn.preparestatement (SQL); Ptmt.setfetchsize (2); RS=Ptmt.executequery (); while(Rs.next ()) {System.out.println (rs.getstring ("UserName") + ":" + rs.getstring ("Coursename"))); } } Catch(SQLException e) {e.printstacktrace (); } finally { Try { if(conn!=NULL) Conn.close (); if(ptmt!=NULL) Ptmt.close

String classScanner in =NewScanner (system.in); System.out.println ("Enter a string to check if it is a palindrome"); Original=In.nextline (); intLength =original.length (); for(inti = length-1; I >= 0; i--) Reverse= Reverse +Original.charat (i); if(original.equals (reverse)) System.out.println ("Entered string is a palindrome."); ElseSystem.out.println ("entered string isn ' t a palindrome."); }} Public int Countword (String Word, file file) {int count = 0new Scanner (file); while (Scan

with a mediation object.Policy mode strategy: The policy pattern defines a series of algorithms, encapsulates them one by one, and enables them to replace each other.Template mode: Defines an algorithm skeleton in an operation, and delays some steps into subclasses.Observer Mode (OBSERVER): Defines a one-to-many dependency that allows multiple observer objects to listen to a Subject object at the same timeIterator mode (Iterator): Iterator mode provides a way to sequentially access individual e

Java beginner course video practice-Beginner online, quiz game, ATM practice, welcome to watch, atm practice Java introductory course video practice-elementary The upload is complete. Welcome to the audience Go directly: Htt

[JAVA concurrent programming practice] 3. Synchronization container and java practice The synchronization containers include Vector and Hashtable, and some are created by factory methods such as Collections. synchronizedXxx. 1. Synchronization container Problems Synchronization containers are thread-safe, but sometim

[JAVA concurrent programming practice] 10. concurrent program testing and java practice1. Generate a random number Package cn. study. concurrency. ch12; public class Util {public static int xorShift (int y) {// shift left and unsigned right, and last XOR operation (XOR, if the two bits are different, the value is 1; otherwise, the value is 0) y ^ = (y 2. cache

Java course practice log (Thursday) and java practice log Import java. awt. eventQueue; import javax. imageio. imageIO; import javax. swing. JFrame; import javax. swing. JPanel; import javax. swing. border. emptyBorder; import javax. swing. abstractButton; import javax. swin

[JAVA concurrent programming practice] 8. Lock sequence deadlock and java practice Package cn. study. concurrency. ch10; public class Account {private String staffAccount; // Account private String passWord; // passWord private int balance; // Account balance public Account (int money) {this. balance = money;} public S

[JAVA concurrent programming practice] 11. Implementation of bounded cache and java practice1. bounded cache base class Package cn. xf. cp. ch14;/*** function: bounded cache implementation base class * Time: 2:20:00 * file: BaseBoundedBuffer. java * @ author Administrator ** @ param 2. Determine the prerequisites befo

[JAVA concurrent programming practice] 9. Lock segmentation and java practice Package cn. study. concurrency. ch11;/*** lock segmentation * @ author xiaof **/public class StripedMap {// synchronization policy: locks the array in segments, n nodes use the n % LOCKS lock to protect private static final int N_LOCKS = 16;

].substring (2)) *0.0001+this.getpoint ( Pukes[1].substring (2)) *0.000001+this.getpoint (pukes[0].substring (2)) *0.00000001;}Return This.getpoint (pukes[4].substring (2)) *0.01+this.getpoint (pukes[3].substring (2)) *0.0001+this.getpoint ( Pukes[2].substring (2)) *0.000001+this.getpoint (pukes[1].substring (2)) *0.00000001+this.getpoint (Pukes[0]. SUBSTRING (2)) *0.0000000001;}public void init () {while (true) {This.createpuke ();This.sortedpuke ();This.createplayer ();if (flag) {This.showpuke

) {System.out.println ("Driver load Failed"); E.printstacktrace (); }//2 connect String URL = "Jdbc:mysql://localhost/test?use analysis: Ssl=true"; String user = "root"; String password = "root"; try {con = drivermanager.getconnection (url, user, password); System.out.println ("link succeeded"); } catch (SQLException e) {System.out.println ("link failed"); E.printstacktrace (); }//3 Statement object try {sql = con.creates

Practice: Java Virtual Machine 2 "virtual machine working mode", Java Virtual Machine Today, I started to practice Java Virtual Machine II: "virtual machine working mode ". 5 Series in total One of the actual Java virtual machin

itDuring the development process, because of the need to constantly modify the code, so during debugging, you can use dynamic loading mode, load user-defined class.Re-edit the Classpath.txt file to remove Dog.jar loading information.Run the following command in MATLAB:>> javaaddpath ('/home/your_username/documents/matlab_java/dog.jar ') >> d = javaobject (' Dog ', ' martin ') d = [Email protected] >> D.getname () ans = martin_1The experimental results also show that the dog is loaded and called