-Xms is used to set the maximum amount of memory that an application can use. If the program needs to consume a lot of memory, you need to modify the value to increase this number.

Xms is used to set the size of the memory stack when the program is initialized. If you increase this value, the startup performance of the program will be improved.

Therefore, the parameters of the two can be configured according to the size of the program and the actual configuration of the computer, and the unit of the parameters is m (megabytes).

Introduction to Java

Java is an object-oriented programming language, which can write cross-platform application software. Java technology has excellent universality, high efficiency, platform portability and security, and is widely used in PCs, data centers, game consoles, scientific supercomputers, mobile phones and the Internet, and has the largest professional community of developers in the world.

major constituent

Java consists of four aspects:

●Java programming language, namely grammar.

●Java file format, that is, suffixes of various folders and files.

●Java Virtual Machine (JVM), that is, the interpreter that handles *. Class file.

●Java application programming interface (Java API).

system

Java is divided into three systems, namely:

Java SE(J2SE, Java2 platform standard edition, standard edition),

JavaEE(J2EE, java2platform, Enterprise Edition, Enterprise Edition)

Java ME(J2ME, Java 2 platform mini version, mini version).