Java JDK, JRE and JVM

什么是JVM

JVM (Java Virtual Machine)有多个解释，它可以是Java虚拟机工作的规范，也可以是满足规范的计算机程序

Java源码-->编译器-->Java字节码-->JVM虚拟机-->机器码-->CPU执行-->输出

什么是JRE

JRE (Java Runtime Environment) is a software package that provides Java class libraries, Java Virtual Machine (JVM), and other components that are required to run Java applications.

JRE is the superset of JVM.

如果你只是运行Java程序，并不开发Java程序，那么你需要JRE。

什么是JDK

JDK (Java Development Kit) is a software development kit required to develop applications in Java. When you download JDK, JRE is also downloaded with it.

In addition to JRE, JDK also contains a number of development tools (compilers, JavaDoc, Java Debugger, etc).

如果你是Java开发者，那么你需要JKD.

三者的关系

文章来源:https://www.programiz.com/java-programming/jvm-jre-jdk