Java

A java.lang.UnsupportedOperationException exception occurred when calling Add,remove these method after using Arrays.aslist (). This is because Arrays.aslist () returns java.util.arrays$arraylist instead of ArrayList. Arrays$arraylist and ArrayList

The Exec method of runtime is often used to record standard usage and make it easier to copy code later.Process process; String cmd = "cat/sys/devices/virtual/mxc_edid_class/mxc_edid_dev/timing"; StringBuffer SB =New StringBuffer ("");Try{process =

Today I see an interface defined in a Java class, write a memo, record1 Packagecom.gxf.test;2 3 Public classTest_interface {4 Public Interfaceshow{5 Public voidShow ();6 }7 Static classTestInterfaceImplementsshow{8 9

Here is an example of a list combination, First look at the following code: public static arraylistdatas=new arraylist ();//Initialize data public static void InitData () {for ( int i=0;i If you run this way, you will definitely get an exception.

/*Enter a string of lowercase letters (A~Z) through the keyboard. Write a string filter to filter out characters that are not the first occurrence if multiple identical characters appear in the string.For example, the string "ABACACDE" filter result

Item 1: Consider static factory methods instead of constructorsAdvantage:One advantage of static factory methods is, unlike constructors, they has names.A second advantage of static factory methods is, unlike constructors, they was not required to

Garbage collection policy in JavaGarbage collection problems Who needs to be recycled When to recycle How to recycle who needs to be recycledIf an object is no longer used, it can be recycled. The key is how to know that an object is no longer

Spring uses annotations to execute scheduled tasks 1. Add the following configuration in SpringContext. xml 1. Add xmlns to beans: task xmlns:task="http://www.springframework.org/schema/task" 2. Add in xsi:

Practical application of Singleton ModeFrom the perspective of face object: although they can achieve their goals, they are object-based and object-oriented, just as we can solve problems without face object, the code of the Surface object provides

SLF4J log front and slf4j front SLF4J Official Website: http://www.slf4j.org/ In general, SLF4J enables our project to replace different log systems at minimal cost. You do not need to modify the code. You only need to add or delete the

Design Mode-decorator ModeDecorator is defined as a Decorator mode. Instead of adding or modifying class attributes in a derived class, the Decorator dynamically designs the Decorator mode to achieve this effect. It is more convenient and flexible

A bug caused by an image of Struts2, struts2bug Open a project as usual today. Write for a while to save the test. An error occurred while logging on. Ah, yesterday was good. Starting to find bugs The core error code is as follows: 10:34:46, 442

Internal Sorting Algorithm (I): Exchange sorting (Bubble sorting, fast sorting) This is the first article in my blog series "Internal sorting algorithms. Sorting is to sort records in files in ascending (or descending) Order of keywords. The

About custom Dialog Dialog is the legendary pop-up box. Some of the layout and functions provided by the system are relatively simple and generally cannot meet the development requirements. Therefore, we need to implement a custom Dialog by

Steps for using hibernate4 for data persistence To use hibernate for Data Persistence: 1. Write persistence class: POJO + ing File 2. Get the Configuration object Configuration is mainly used to manage the Configuration information of hibernate and

Randomize one-dimensional array A problem: Assume that there is a one-dimensional integer array that is randomization, even if each element appears randomly in the array, and the probability is the same. Ii. Solution ideas: 1. Construct two arrays,

JavaSE-a simple program inspired new users A simple program: Question: now we have completed a simple program that can output the multiplication of two numbers. Public class TestJava {public static void main (String args []) {int num = 10; //

Target -- action design mode and delegate Design Mode 1. tar get -- action design mode 1. create a View Controller in the View Controller. in the m file, create the CustomView (subclass of UIView) object CustomView * blueView = [[CustomView alloc]

Design Mode-Combination ModeComposite definition: combines objects into a tree structure to represent hierarchical relationships, and allows objects to be presented to client programs in the same way. For example, the compilation of family genealogy:

Many problems that occur when JAVA collections remove their own set ElementsThe purpose of a piece of code is to delete the set items that contain the "a" string in the collection: public class TestForeach {public static void main(String[]