a a safety

Public classMyObject {Private volatile StaticMyObject MyObject; PrivateMyObject () {} Public StaticMyObject getinstance () {Try { if(MyObject! =NULL){ }Else{Thread.Sleep (3000); synchronized(MyObject.class) { if(MyObject = =NULL) {MyObject=NewMyObject (); } } } } Catch(Exception e) {e.printstacktrace (); } returnMyObject; }}A single-instance mode of thread

What is the problem with a single meeting? If multiple threads call this instance at the same time, there will be a thread security issueWhat is the general use of a single case?The purpose of the singleton is to ensure that there is only one instance of the runtime, the most common places such as getting a connection

This paper describes the security scheme of YII framework framework. Share to everyone for your reference, as follows: Web application security issues are important, in the "hacker" era, your site may be under attack tomorrow, in order to prevent the attack in some way, Yii provides several solutions to prevent attacks. Of course, the security here is one-sided, but it is worth seeing. The official solutions are as follows: 1. Prevention of cross-site scripting attacks Cross-site scripting atta

Function After the conversion, you can take the blasting tool to run .... The port reads like this after the 223,34,0,0 You can use the following code to convert [Copy to Clipboard] [-] CODE: Dim Thestr Thestr = InputBox ("Enter the port to be converted:", "Input", "223,34,0,0,") da = Split (Thestr, ",",-1, 1) If thestr Call InputBox ("Please copy the ports that have been converted", Hex2dec (Dec2hex (DA (3)) dec2hex (DA (2)) dec2hex (DA (1)) dec2hex (DA (0))) End If Function Hex2dec (Hex)

Author: Xi4oyu One test: [Xiaoyu@localdomain ~]$ Echo $BASH _env [Xiaoyu@localdomain ~]$ export bash_env= "/TMP/.BASHRC" [Xiaoyu@localdomain ~]$ Echo $BASH _env /tmp/.bashrc [Xiaoyu@localdomain ~]$ CAT/TMP/.BASHRC #!/bin/bash echo "Hello" [Xiaoyu@localdomain ~]$ Ls-l -rwxrwxr-x 1 Xiaoyu xiaoyu 2008-09-11 05:54 test.sh [Xiaoyu@localdomain ~]$ Cat test.sh #!/bin/bash echo "KK" [Xiaoyu@localdomain ~]$./test.sh Hello Kk Well, that's good, as we expected. Let's see how we use it. grep su ~/.b

Tags: King Wheel Electric Car King wheel bicycle 420103000263023 After Yang Yi's departure, Liu Feng, Wuhan Jinshi Zhongding Trading Co., Ltd., spent some time in huoyundong, and estimated that the time was almost the same. Then he left the three emperors and Jinding WangLun electric car, back to biyou Palace.At this time, after such a long time of drills and insights, the master of the King wheel flying high brother was chosen by him. With the help o

In the Web development process, we often have to get data from users from all over the world. However, we "can never trust the data entered by those users." Therefore, in a variety of web development languages, will provide a guarantee of user input data security functions. In PHP, there are some very useful and handy functions that can help you prevent problems like SQL injection attacks, XSS attacks, and

PS: Previous articlesBlogI mentioned it, but it is still a little difficult to apply it well, so I will discuss these small functions. Problem Background: Currently, a smallCaseIs aboutDeltaSelf-built data sources of the Mechanism are always unable to extract data. Cause: BW's delta mechanism is to record a timestamp in the system, su

Copy Code code as follows: Package net.kitbox.util; /** * * @author Lldy * */ public class Singleton { Private Singleton () { } private Static Class singletonholder{ private static Singleton instance = new Singleton (); } public static void Method () { Singletonholder.instance._method (); } private void _method () { System.out.println ("Singleton method!"); } public static void Main (string[] args) { Singleton.method (); } } This notati

[Problem] 1. Division is not required. Two arrays A [n], B [N], where each element value of a [n] is known, and B [I] is assigned a value, B [I] = A [0] * A [1] * A [2]... * A [N-1]/

Two arrays a [N], B [N], where each element value of A [N] is known, and B [I] is assigned a value, B [I] = a [0] * a [1] * a [2]… * A [N-1]/a