Core Java Volume I — 3.10. Arrays

3.10. ArraysAn array is a data structure that stores a collection of values of the same type. You access each individual value through an integer index. For example, if a is an array of integers, then a[i] is the ith integer in the array.Declare an a…

Core Java Volume I — 4.10. Class Design Hints

4.10. Class Design HintsWithout trying to be comprehensive or tedious, we want to end this chapter with some hints that will make your classes more acceptable in well-mannered OOP circles. 1. Always keep data private. This is first and foremost; doin…

Core Java Volume I — 1.2. The Java "White Paper" Buzzwords

1.2. The Java "White Paper" BuzzwordsThe authors of Java have written an influential White Paper that explains their design goals and accomplishments. They also published a shorter summary that is organized along the following 11 buzzwords:1. Si…

Core Java Volume I — 4.7. Packages

4.7. PackagesJava allows you to group classes in a collection called a package. Packages are convenient for organizing your work and for separating your work from code libraries provided by others.The standard Java library is distributed over a numbe…

Core Java Volume I — 5.1. Classes, Superclasses, and Subclasses

5.1. Classes, Superclasses, and SubclassesLet's return to the Employee class that we discussed in the previous chapter. Suppose (alas) you work for a company at which managers are treated differently from other employees. Managers are, of course, jus…

Core Java Volume I — 3.8. Control Flow

3.8. Control FlowJava, like any programming language, supports both conditional statements and loops to determine control flow. We will start with the conditional statements, then move on to loops, to end with the somewhat cumbersome switch statement…

Core Java Volume I — 4.6. Object Construction

4.6. Object ConstructionYou have seen how to write simple constructors that define the initial state of your objects. However, since object construction is so important, Java offers quite a variety of mechanisms for writing constructors. We go over t…

Core Java Volume I — 4.5. Method Parameters

4.5. Method ParametersLet us review the computer science terms that describe how parameters can be passed to a method (or a function) in a programming language. The term call by value(值调用) means that the method gets just the value that the caller pro…

Core Java Volume I — 4.4. Static Fields and Methods

4.4. Static Fields and MethodsIn all sample programs that you have seen, the main method is tagged with the static modifier. We are now ready to discuss the meaning of this modifier.4.4.1. Static Fields(静态域)If you define a field as static, then there…

Core Java Volume I — 3.6. Strings

3.6. StringsConceptually, Java strings are sequences of Unicode characters(Java的字符串是一个Unicode序列). For example, the string "Java\u2122" consists of the five Unicode characters J, a, v, a, and ?. Java does not have a built-in string type(Java没有内置的…

Core Java Volume I — 3.5. Operators

3.5. OperatorsThe usual arithmetic operators +, -, *, / are used in Java for addition, subtraction, multiplication, and division. The / operator denotes integer division if both arguments are integers, and floating-point division otherwise. Integer r…

Core Java Volume I — 3.4. Variables

3.4. VariablesIn Java, every variable has a type. You declare a variable by placing the type first, followed by the name of the variable. Here are some examples: double salary; int vacationDays; long earthPopulation; boolean done; Notice the semicolo…

Core Java Volume I — 3.3. Data Types

3.3. Data TypesJava is a strongly typed language(强类型语音). This means that every variable must have a declared type(每个变量都必须声明类型). There are eight primitive types in Java(Java有8种原始类型). Four of them are integer types; two are floatingpoint number types;…

Core Java Volume I — 4.1. Introduction to Object-Oriented Programming

4.1. Introduction to Object-Oriented ProgrammingObject-oriented programming, or OOP for short, is the dominant programming paradigm these days, having replaced the "structured," procedural programming techniques that were developed in the 1970s.…

Core Java Volume I — 3.1. A Simple Java Program

Let’s look more closely at one of the simplest Java programs you can have—one that simply prints a message to console: public class FirstSample { public static void main(String[] args) { System.out.println("We will not use 'Hello, World!'"); } }…

Core.Java.Volume.I.Fundamentals.10th.Edition 14.5.8 Volatile域中文版章节勘误

今天重扫了corejava 14 并发的一章,在谈到volatile域代替synchronized 应用于并发更新时,看到如下内容,并发更新可用内部锁的方式但会带来阻塞问题,可用volatile域替代.个人发觉好像有哪里欠了点逻辑,似乎volatile域为什么能替代内部锁并没有讲明原因.秉承着疑惑对了一下原版. 果然在原版中多了这么一句解释: The compiler will insert the appropriate code to ensure that a change to the…

Difference Between Arraylist And Vector : Core Java Interview Collection Question

Difference between Vector and Arraylist is the most common Core Java Interview question you will come across in Collection . This question is mostly used as a start up question by the Interviewers before testing deep roots of the Collection .Vec…

Core Java Interview Question Answer

This is a new series of sharing core Java interview question and answer on Finance domain and mostly on big Investment bank.Many of these Java interview questions are asked on JP Morgan, Morgan Stanley, Barclays or Goldman Sachs. Banks mostly asked c…

201521123082 《Java程序设计》第10周学习总结

201521123082 <Java程序设计>第10周学习总结标签(空格分隔): java 1. 本周学习总结 1.1 以你喜欢的方式(思维导图或其他)归纳总结异常与多线程相关内容. Answer: 2. 书面作业本次PTA作业题集异常.多线程 1.finally 题目4-2 1.1 截图你的提交结果(出现学号) Answer: 1.2 4-2中finally中捕获异常需要注意什么? Answer: 先贴上finally块的源码: finally { try { resource.clos…

Top 25 Most Frequently Asked Interview Core Java Interview Questions And Answers

We are sharing 25 java interview questions , these questions are frequently asked by the recruiters.Java questions can be asked from any core java topic . So we try our best to provide you the java interview questions and answers for experienced whic…

Java数组操作的10大方法

转载自码农网译文链接:http://www.codeceo.com/article/10-java-array-method.html 英文原文:Top 10 Methods for Java Arrays 翻译作者:码农网 – 小峰下面是精心整理的Java数组操作的10大方法,大部分代码都来自Stack Overflow. 0.定义一个Java数组 String[] aArray = new String[5]; String[] bArray = {"a","b&qu…

201621123080 《Java程序设计》第10周学习总结

201621123080 <Java程序设计>第10周学习总结 1. 本周学习总结 1.1 以你喜欢的方式(思维导图或其他)归纳总结异常相关内容. 2. 书面作业本次PTA作业题集异常 1. 常用异常结合题集题目7-1回答 1.1 自己以前编写的代码中经常出现什么异常.需要捕获吗(为什么)?应如何避免? 以前常遇到ArrayIndexOutOfBoundsException NullPointerException ClassCastException NumberFormatExcept…

20145212 《Java程序设计》第10周学习总结

20145212 <Java程序设计>第10周学习总结学习内容总结一.Java的网络编程网络编程是指编写运行在多个设备(计算机)的程序,这些设备都通过网络连接起来. java.net包中J2SE的API包含有类和接口,它们提供低层次的通信细节.你可以直接使用这些类和接口,来专注于解决问题,而不用关注通信细节. java.net包中提供了两种常见的网络协议的支持: TCP: TCP是传输控制协议的缩写,它保障了两个应用程序之间的可靠通信.通常用于互联网协议,被称TCP / IP. UDP:…

20145206《Java程序设计》第10周学习总结

20145206 <Java程序设计>第10周学习总结博客学习内容总结什么是网络编程网络编程就是在两个或两个以上的设备(例如计算机)之间传输数据.程序员所作的事情就是把数据发送到指定的位置,或者接收到指定的数据,这个就是狭义的网络编程范畴.在发送和接收数据时,大部分的程序设计语言都设计了专门的API实现这些功能,程序员只需要调用即可. 计算机网络概述 ·路由器和交换机组成了核心的计算机网络,计算机只是这个网络上的节点以及控制等,通过光纤.网线等连接将设备连接起来,从而形成了一张巨大的计算…

applet示例 WelcomeApplet.java <Core Java>

import java.awt.BorderLayout; import java.awt.EventQueue; import java.awt.Font; import java.awt.Graphics; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.net.URL; import javax.swing.JApplet; import javax.swing.JBu…