Java [1] is an object-oriented programming language that can write cross-platform application software. It is the general name of the Java programming language and Java platform (i. E., JavaCE, JavaEE, JavaME, JavaSE) launched by Sun Microsystems in May 1995. Java has been very popular and developed rapidly since its advent, which has had a strong impact on the C++ language. Java technology has excellent versatility, efficiency, platform portability and security. It is widely used in personal PCs, data centers, game consoles, scientific supercomputers, mobile phones and the Internet. It also has the world's largest professional community of developers. In the global industrial environment of cloud computing and mobile Internet, Java has significant advantages and broad prospects.