摘要： In this tutorial we are going to see how to ZIP a file in Java. ZIP is an archive file format that enables data compression and it is mostly used on files and folders. A ZIP file may contain one or more compressed files or folders. Many compression algorithms have been used by several ZIP implementa 阅读全文

摘要： ByX WangUpdate History:Web Versionlatest update: 4/6/2014PDF Versionlatest update: 1/16/2014The following are top 10 algorithms related topics for coding interviews. As understanding those concepts requires much more effort, this list below only serves as an introduction. They are viewed from a Java 阅读全文

摘要： This article explains the internal architecture of the Java Virtual Machine (JVM). The following diagram show the key internal components of a typical JVM that conforms toThe Java Virtual Machine Specification Java SE 7 Edition.The components shown on this diagram are each explained below in two sec 阅读全文

摘要： Understanding how Java code is compiled into byte code and executed on a Java Virtual Machine (JVM) is critical because it helps you understand what is happening as your program executes. This understanding not only ensures that language features make logical sense but also that it is possible to un 阅读全文

摘要： BYADMIN-APRIL, 9TH 2014The ‘PING’, it’s a command-line tool to check a host is reachable or not. We can manage it by the help of ‘iptables’. The ‘ping’ is using ICMP to communicate. We can simply manage the ‘icmp : Internet Controlled Message Protocol’ from iptables.Required iptables switchesThe bel 阅读全文

摘要： The release of Spring 2.5 reduce the burden of XML by introduction annotation based configuration, but you still needed to bootstrap Spring in XML. However in Servlet 3 and Spring 3.1 we can now drop XML completely and have 100% code based configuration. All thanks to the Servlet 3 specification.So 阅读全文

摘要： In this tutorial, we will see how we can use Spring security to protect specific resources. This Hello World tutorial will give you a quick start to Spring Security.We will use Spring’s Java Config ( Annotation based approach) to configure the properties instead of XML configuration.Technologies use 阅读全文

摘要： How to check if an array (unsorted) contains a certain value? This is a very useful and frequently used operation in Java. It is also a top voted question on Stack Overflow. As shown in top voted answers, checking if an array contains a certain value can be done in several different ways, but the ti 阅读全文

摘要： 如果tar不支持j这个参数就先用bzip2 -d xxx.tar.bz2把它解压成.tar文件，然后再用tar xvf xxx.tar拆包。压缩解压linux下怎么解后缀名是gzip的文件？1.以.a为扩展名的文件:#tar xv file.a2.以.z为扩展名的文件:#uncompress file.Z3.以.gz为扩展名的文件:#gunzip file.gz4.以.bz2为扩展名的文件:#bunzip2 file.bz25.以.tar.Z为扩展名的文件:#tar xvZf file.tar.Z或 #compress -dc file.tar.Z | tar xvf -6.以.tar.gz/ 阅读全文

摘要： 今天在做报表查询的时候Oracle报错：信息为 ORA-01810: format code appears twice原因：由于想java一样转化时间格式，但是Oracle中是不区分大小写的，所以格式最终为select count(*) as k2 ,t.cityid as k1 fromportal_user t wheret.createtime >= to_date(#YbeginTime#,'yyyy-mm-dd HH24:mi:ss')and to_date(#YendTime#,'yyyy-mm-dd HH24:mi:ss')>=t.c 阅读全文