Java

Experimental Purpose:1) Understanding The composition and structure of JDBC2) Mastering The link Technology of Java program and database3) Master the DriverManager class, Connection,provided in the Java program using the java.sql Package

Bitwise operators :>>> unsigned right-shift operators, the rules for unsigned right shifts are the same as those that move right, except that when they are filled, they are supplemented with zeros, regardless of whether the original is positive or

Flying Pigeon RPC is a very lightweight, easy-to-modify remote call framework that is integrated into real projects, developed based on the NIO framework Netty, easily supports high concurrency, supports service load balancing, seamlessly integrates

Java IO principleIO streams are used to process data transfer between devicesInput: Read external data (disk, etc storage device) to program ()(In memory)Output: Output program (memory) data to a storage device such as diskJava IO principleIO

When unpacking a jar file or zip file in Java, you can use the built-in Api:jarfile and ZipFile of the JDK to extract the 2 format files under Windows, often reporting the following error:Exception in thread "main" Java.lang.IllegalArgumentException:

Synchronized locks the object, and when the object is initialized, the JVM calls the block of statements outside the method before the object is initialized, and the object does not exist, so there is no lock.So what's the difference between static

Do not say the pattern of the problem, look at a > inside examples.The boss wants to see the company's various projects. (I know I have a big head look at this overview, see the code.)Sample Program V1Package iterator;/** * @author cbf4life

Exception This exception is divided into two major classes of runtime exceptions and non-runtime exceptions (compilation exceptions). These exceptions should be handled as much as possible in the program.Run-time Exceptions: both the

Concurrent containersJava 5.0 provides a variety of concurrent containers to improve the performance of the synchronization container.The synchronization container is the serialization of all access to the container to implement their thread

1. Convert an array to a listWhen you convert an array to a list, programmers often do this: 1 List list = Arrays.asList(arr); Arrays.asList()Returns a ArrayList object, the ArrayList class is a private static class

1. hash table Interface ClassPackage cn.usst.hashtable;/** * Hash List interface class * @author G-xia * */public interface Hashtable {///to a hash list insert a keyword thekey element obj, if successful return True otherwise returns a false Boolean

A comprehensive example that demonstrates concurrent read and write of a finite-length character sequence buffer, or producer-consumer issues. The point of omission, please indicate ^_^/** * Pcproblem: * Simulation Producer-consumer problem,

/** * Problem Description: Prints all truth combinations for a given n boolean variable. * For example, n = 2 o'clock, all truth combinations are (true, false), (true, True), (false, True), (false, False). * * Basic idea of the algorithm: * Use an

1. java.lang.NullPointerExceptionThis exception everyone must often encounter, the exception of the explanation is that the " program encountered a null pointer ", simply called an uninitialized object or a nonexistent object, this error

1 ImportJava.text.DateFormat;2 ImportJava.text.SimpleDateFormat;3 Importjava.util.Date;4 ImportJava.util.Calendar;5 ImportJava.util.GregorianCalendar;6 7 Public classOct_18_timeanddateformat {8 9 Public Static voidMain (string[] args) {Ten

Java.io.File class 1. Generally related to the input and output classes, interfaces, etc. are defined under the Java.io package 2.File is a class that can have constructors to create its objects. This object corresponds to a file (. txt. avi. doc.

Ext.: http://www.blogjava.net/xylz/archive/2010/07/02/325079.htmlIn this section, we begin to discuss array atomic operations and some other atomic operations.Atomicintegerarray/atomiclongarray/atomicreferencearray 's API is similar, select a

There are many numbers that are stored in arrays, There are many objects that need to be stored togetherBut the array is fixed-length, and the set is variable-lengthThe origin of the collection:Objects are used to encapsulate unique data, objects

Java InnerClass (innerclass) ---- non-static internal class, static internal class, local internal class, anonymous internal class, Department class InnerClass Many people are not familiar with the java underwear Class. In fact, similar concepts

JAVA course 31st (Common Object API)-StringBuffer Class & amp; StringBuilder class StringBuffer class The principle of string composition is implemented through this class StringBuffer can add or delete string content StringBuffer is a