how long take to learn java

This article assumes that the reader does not understand anything, or has to toss some language, such as C, but the beginner. Classic case, HelloWorld start, learn a language in the understanding, I try to explain why to write, it is very likely that the designer is not designed according to this idea, Java is an object-oriented language, in the object-oriented world, they classify a lot of things, for shor

Because of my own development in the iPhone, for the original C # I (also do too large for half an android), OBJECTIV-C is indeed a very headache, although I learned several chapters, but for OBJECTVE-C still seem to understand not understand, so today on the net search some information, visit to a place, found this article is good, recommended to everyone, reprint oh, not my original: Most beginners who have a basic development experience on other platforms are eager to see xcode. After seeing

className. will produce a java.hprof.txt file.107. Throwable is the parent of error handling in all Java programs, there are two types of funds: Error and exception.108. Error: Represents the unexpected errors detected by the JVM, because this is a critical error that is part of the JVM hierarchy, causing the JVM to fail Continued, therefore, this is not captured, can not take any recovery operation, can o

Dark Horse training camp to study. Go to the official website to download the Java Learning Video, listen to the teacher's course to get started Java. Of course, in the process of registration, because of their own personality problems, go very slowly (on the one hand, fear of their own foundation is too poor to pass the entrance examination, on the other hand is afraid that they can not follow the course

Turn fromHttp://www.cnblogs.com/Coda/p/4331432.htmlI believe you have learned that Java has cross-platform features that can be "compiled once, run Everywhere", programs written under Windows can run under Linux without any modification, which is difficult for C and C + +.So how does a cross-platform implement it? This will refer to the Java Virtual machine (Java

Study Excerpt address: http://blog.csdn.net/chenleixing/article/details/44573495Today to learn and understand, filter and SPRINGMVC of the difference between the interceptor, learned a lot of things, has always thought that the interceptor is a filter to achieve, now think of is really a mistake ah, and look at the relatively superficial, not a global and meticulous understanding, due to the late night, time reason, I will

In Java, variable types fall into two main categories: primitive types and reference types. Although the auto-boxing and auto-unpacking mechanisms have been introduced after JDK1.5, we have greatly reduced our entanglement between the direct and reference types, but there are still some issues that we have to consider. For example, I encountered a problem with the base type and the default value of its wrapper type, such as generics can only use refer

Struts is one of the three most famous SSH frameworks, still playing an important role in the Java Web today, in the MVC mode, which is responsible for the various JSP pages and action scheduling control (Controller), the following is the basic configuration of Struts2 under Eclipse.First, the preparatory work1. Before the struts configuration, the Eclipse environment variables are configured by default and the Tomcat server is deployed;2. Download th

Sender: Linuxandjava (Linuxandjava), letter area: Java Title: First Solution to learning Java Letter Station: NetEase Virtual Community Beijing station (Thu APR 20 09:59:51 2000), Station letters Although there are not many commercial Java works in the country, the number of people learning Java has been propped up st

Follow the examples to learn java multithreading 6-how to correctly publish thread-safe objects, java6- Everything we mentioned above is only for the purpose of correctly releasing a thread-safe object. I. Closed threads This is easy to understand. If a variable changes its status in a thread, the variable must be thread-safe. We often use stack closures and ThreadLocal classes. There is a virtual machine s

these documents to achieve some client dynamic effects. JS's territory is not only so, now node. JS can also be used for server-side development.Main do: Front-end development of the website Show off all kinds of cool pictures PhpBottom line: "PHP is the best language in the world" of course, it's just a terrier.PHP is mainly: Network Front end Used to generate Web pages Web server: Forum engine Python"Life is short, I use Python."Python has a rich and po

reference "value" equal, as to the object of this address is equal to the content, = = operator is regardless. Understanding the final question has a very important meaning. Many program vulnerabilities are based on this----final can only guarantee that the reference always points to the fixed object, and cannot guarantee that the object's state is unchanged. In a multithreaded operation, an object is shared or modified by multiple threads, and a thread's unconscious modification of the object

"I haven't written this series for a long time. In fact, there are also in the look, but feel some very basic are written up boring. Now the plan is to read the whole book, and finally integrated into a blog, to filter out some of the usual unnoticed or more in-depth understanding "In the writing program, string strings are very much manipulated. The use of strings in peacetime only uses a subset of features. This time we'll look at what the main thin

of an anonymous class, and dynamically creating an instance of the anonymous class. The benefits of this writing are obvious, using interfaces to contract, and then actually using the business code when it is used. This makes the code much leaner, without the need to create a bunch of Java code units.However, if the class needs to be named and reused, it is less appropriate to use this approach, or there will be a lot of duplicated code. When looking

Hello, little friends. With the release of the first two posts, many small partners have been able to enter the learning phase, never learn Java to start learning Java such a process, today, TAM teacher mainly talk about the problem of learning mentality.1. I compared with the other classmates in the class, I do not have them fast, digestion than they slow, I am

Learn about java encryption and PHP, and help me solve it. Importjava. security. messageDigest; Strings = quot; I am abc quot; byte [] B = s. getBytes ( quot; UTF8 quot;); for (learn about java encryption and PHP, and help me solve it. Import java. security. MessageDiges

method. Declaring a generic method is simple, as long as the return type is preceded by a similar Public class Util { Public static boolean compare (Pairreturn P1.getkey (). Equals (P2.getkey ()) P1.getvalue (). Equals (P2.getvalue ());}} Public class PairPrivate K key;Private V value; Public Pair (K key, V value) {this. Key = key;this. Value = value;} Public void Setkey (K key) { this. Key = key;} Public void SetValue (V value) { this. Value = valu

methods.　　② down transformation and runtime type recognitionAs the upward transformation loses the specific type information, we think that by going down the transformation should be able to get type information, in the Java language, all transformations will be checked. If the type does not match, a classcastexceptionis returned. This behavior of checking the type during run is called Runtime type recognition (RTTI).5. Summary Polymorphism means "di

Well-off will accompany you to learn JAVA -------- comparison between continu3 and break, javabreak This article compares continu3 with break. In the Java language, there are some jumping statements, such as break and continue, which are not encouraged from the perspective of structured program design, these skip statements increase debugging and reading difficul

In the previous chapters we are all directly managing thread, and here we explain another class executors that manages thread.1. Example:Package Com.ray.ch17;import Java.util.concurrent.countdownlatch;import Java.util.concurrent.ExecutorService; Import Java.util.concurrent.executors;public class Test {public static void main (string[] args) throws interruptedexception {Long startTime = System.currenttimemillis (); Executorservice Executorservice = Exe