A. Download jdk
The JDK is the acronym for Java Development Kit, which is the core of the entire Java system, including the Java Runtime Environment (Java Runtime envirnment), Java tools, and Java-based class libraries (Rt.jar). No matter what Java application server is in essence a version of the JDK is built in. So mastering the JDK is the first step in learning Java.
The Java Development Toolkit is available for free download. If you need to be able to download the corresponding JDK for installation depending on the operating system platform, you can also download the corresponding JDK through the URL address provided in my article. The latest version of the JDK is jdk1.6.0_04, where I'll take the Solaris platform as an example to describe the download process as follows:
1. In the browser address bar type "http://java.sun.com/javase/downloads/index.jsp
2. Find the JDK 6 Update 4 Item, click the "Download" button at the end, select "Solaris" in the Drop-down menu, and in the option that you agree to
Tick, and then click "Continue" below.
3. Select "Java EE 5 SDK Update 4" and click "jdk-6u4-solaris-i586.sh" to download the JDK for the Solaris operating system.