java nanodegree

in theJava, abnormal conditions are divided intoException(Exception) andError(Error) Two major categories,Javaexception usually refers to the program during the operation of abnormal conditions, such as user input errors, divisor is zero, need to deal with the file does not exist, array subscript out of bounds, for the occurrence of abnormal conditions, can use exception processing, in order to ensure that the program can be normal execution. Java Tw

j2ee| notes Learn some Java EE every week, make some notes. Goal: Be proficient in using WebSphere to do Java EE development work. Come on! Come on!! Come on!!! For example, install under Linux. 1 ready to install J2SE normal user identity:./j2sdk-1_3_1_01-linux-i386-rpm.bin run Setup, finally build jdk-1.3.1_01.i386.rpm file 2 install j2se SDK1) su root: RPM- IV

First, JDK (Java development Kit)The JDK is the core of the entire Java, including the Java Runtime (Java Runtime Envirnment), a stack of Java tools, and a Java-based class library (Rt.jar). Any

My Java development and learning journey ------> Hill sorting of Java's classic Sorting Algorithm ------ javaI. Shell Sort) Shell Sort is an insertion sorting algorithm named after D. L. Shell in 1959. Shell sorting is also called to narrow down incremental sorting. Ii. Basic Ideas of hill sorting The central idea of hill sortingThat is, grouping data and sorting each group of data. After each group of data is sorted, you can sort all groups by inser

The fourth arithmetic program has no operation interface. The java version uses some basic operations in java, and the fourth arithmetic operation is java. This is the first experiment in the experiment outline of this semester's java course. Here we have made a simple version without a user interface. Import

first, the error phenomenon. The Java Project displays red, and a red error is reported in the reference package in the class, and the following error message is displayed below eclipse Second, the cause of the error. It is clear from the literal meaning that the Java version is incorrect. Third, the solution. 3.1 Right-click Project "Properties" on the left side of the "Properties" window tha

Java learning from getting started to proficient Java learning path (1), tools I. JDK (Java Development Kit) JDK is the core of the entire Java, including the Java Runtime Environment (Java runtime envirnment), a bunch of

Java learning path (1), tools I. JDK (Java Development Kit) JDK is the core of the entire Java, including the Java Runtime Environment (Java runtime envirnment), a bunch of Java tools and the Basic

Java basic notes (3: files and data streams), java data streamsI,Input stream and output stream The input stream loads data from files, standard inputs, or other external input devices to the memory. The function of the output stream is the opposite. Data in the memory is saved to a file or transmitted to the output device. The input stream corresponds to the abstract class

Java-static code block, constructor code block, constructor, and Java class initialization sequence. constructor java Static code block: it is declared with staitc. It is executed only once when jvm loads the class.Construct a code block: the class is defined directly with {} and executed every time an object is created.Execution sequence priority: static block,

Java improvements-implement multi-inheritance in Java and inherit from java 　　Multi-inheritance means that a class can inherit behavior and features from more than one parent class at the same time.However, we know thatJava only allows single inheritance to ensure data security. Sometimes we think that multi-inheritance in the system is often a bad design. What w

JAVA learning experience-Summary of JAVA Abstract classes and interfaces, java Abstraction * -- Summarize JAVA Abstract classes and interfaces* 1. abstract class:* 1 abstract classes can be used to modify methods and classes, but cannot modify attributes or be instantiated.* 2 abstract classes can be inherited. They ca

[Java Basics] 4. Internal classes in java, internal classes in java Classification of internal classes: General Internal classes, static internal classes, private internal classes, local internal classes, and anonymous internal classes.Instance 1: regular internal class 123456789101112131415161718192021222324 // External classclassOut {privateintage

Packing classEverything in Java is an object, so many operations are for objects, and Java will automatically wrap the usual data types into objects of the corresponding classes.Support for automatic package and unpacking after jdk1.5Wrapper classes for common data typesPackingBoxing is the object that changes the base data type to the corresponding class.listnew ArrayList();//list的各种操作都是针对对象的list.add(5);//

What are the common languages of Java? without introducing Java idioms, the overall introduction to Java is incomplete. While the source power of Java's birth is portability and security, other factors also play an important role in the final process of Java language formation. Next, green tea small make up Yi Yilai in

Chapter One Introduction to the Java languagefirst, what is Java? Java programming Language: Simple, fully object-oriented, distributed, interpretive, robust, secure and system-independent, portable, high-performance, multi-threaded, and dynamic programming languages.Java can compose cross-platform applications, a generic term for the

1991, I was 7 years old, just entered the academy less than six months. And the computer was also a novelty in that era. But in that environment, Java has sprouted. That year, Sun launched a green plan to develop a software that could run on any consumer electronics product. However, because C + + itself has a lot of shortcomings, so the project team decided to develop a new language Oak. Initially, Oak was applied to the set-top box, but the project

(); Intent.setaction (Intent.action_call); Intent.setdata (Uri.parse ("Tel:" + "123123")); StartActivity (Intent); }}, "Demo"); String Url=new string ("http://192.168.61.173:8080/myweb/zp.html"); Loading Web pages into Web controls weB.loadurl (URL); } }3, the page inside the button to use the hyperlink, the method is as follows:Where the demo is the class name, callous is the method of the demo class, the front window is the tag, plus not so-called

Http://blog.csdn.net/jxzxm1_2/article/details/2499751 An exception occurs when a Java program is used to query a large amount of data from the database:Java. Lang. outofmemoryerror: Java heap SpaceThis exception is thrown if 98% is used for GC and the available heap size is less than 2% in JVM.JVM heap setting refers to the setting of memory space that JVM can allocate during

Jad: decompilation tool download Jad: decompilation Tool Decompiling a class file into a Java File Install jad.exe in the F:/Java/Jad directory. Copy the file *. class to be decompiled to this directory and follow these steps, In the command line window, enter the Jad directory, Then run: Jad-s Java *. Class (Appendix, *. Class indicates the name of the file