Java learning from entry into the master articles 1, JDK (Java Development Kit) JDK is the core of Java, including Java Runtime Envir, a bunch of Java Tools, and Java Base (RT.jar). Regardless of the Java application server, it is built into a version of JDK. So master JDK is the first step in learning Java. The mainstream JDK is the JDK released by Sun. In addition to Sun, many companies and organizations have developed their JDK, such as the JDKTed by IBM, BEA's JROCKET, as well as GNU organizations, etc. . The JVM (Java Virtual Machine) of the IBM's JDK is much higher than the JVM contained in Sun JDK. Jrockets running in the X86 platform are also much better than Sun JDK in the X86 platform. But no matter what, we still need to master Sun JDK first. 1, JDK download and installation JDK is also known as J2SE (Java2 SDK Standard Edition), you can download from Sun's Java website, http://java.sun.com/j2se/downloads.html JDK Current version is J2SDK1 . 4.2, it is recommended to download this version of JDK, download page here: http://java.sun.com/j2se/1.4.2/download.html Download good JDK is an executable installer, the default installation is completed Install a set of JREs in a C: / Program files / java / directory, install a set of JDKs under C: /J2SDK1.4.2 (also including a set of JREs). Then we need to increase Java path C: /J2SDK1.4.2/bin at the forefront of the environment variable Path. This way, JDK is installed. 2, JDK command tool JDK's most important command line tool: Java: Start JVM execution Class Javac: Java compiler JAR: Java package tool Javadoc: Java document generator These command lines must be very familiar, for each parameter It is very proficient. For these commands, there is a detailed documentation on the JDK Documentation. Second, JDK Documentation Documentation also has downloaded connections in JDK's download page, it is recommended to download the documentation at the same time. Documentation is the most important programming manual covers the description of all Java all aspects. It can be said that learning Java programming, most of the time is watching this documentation. I am carrying it with you, when I write Java code, I will see it at any time. Third, the App Server App Server is a platform that runs Java Enterprise Components, which constitutes the main operating environment of the application. The current mainstream App Server is a WebLogic Server and IBM's WebSphere and free JBOS, and one of them can be learned. Personally recommend WebLogic, because it is more convenient, developed and deployed, is Java Enterprise software developers preferred development platform.
The following is a brief introduction to several common App Server: 1. Tomcat Tomcat is not a real app server, it is just a web container that can support running ServerT / JSP, but Tomcat has expanded some App Server features, such as JNDI, database connection pool, user transaction, and more. Tomcat is very widely used in small and medium-sized Java web applications, so this article does a little download, install, and configure Tomcat: Tomcat is a sub-project under the Jakarta project under Apache, its main website is: http: / /jakarta.apache.org/tomcat/ Tomcat latest version is Tomcat4.1.27, software download connection is: http://www.apache.org/dist/jakarta/tomcat-4/binaries/ Download Tomcat can download ZIP directly Pack, you can also download the EXE installation package (personal suggestion zip cleaner), no matter which case, after downloading is installed (ZIP directly decompressed). Need two environment variables: java_home = c: /j2sdk1.4.2catalina_home=d: / tomcat4 (your Tomcat installation directory)
This is installed, start Tomcat Run Catalina_Home / Bin / Startup.bat, close Tomcat running shutdown.bat scripts. After Tomcat starts, the 8080 port is used by default, so you can use your browser to access http: // localhost: 8080 to test whether Tomcat is started normally. Tomcat provides management tools for two web interfaces. The URLs are: http: // localhost: 8080 / admin / index.jsp http: // localhost: 8080 / manager / html first needs before enabling these two management tools Manually configure the administrator user and password. Use a text tool to open Catalina_home / conf / tomcat-users.xml, add the following line:
