java - JDK 代替或补充 JRE？

Question

我对 Java 的两个版本有疑问:JRE(Java 运行时环境)和 JDK(Java 开发工具包)。

JDK 是与 JRE 一起安装和使用的，还是使用它代替 JRE，以便可以将 JDK 作为 JRE 安装并为开发人员提供更多功能？

Answer 1

您必须了解 JDK 包括 JRE。 JRE 是运行 Java 程序的 Java 虚拟机，而 JDK 是功能齐全的 Java 软件开发工具包

来自文档:

JRE (Java Runtime environment):

• It is an implementation of the Java Virtual Machine* which actually executes Java programs.
• Java Runtime Environment is a plug-in needed for running java programs.
• The JRE is smaller than the JDK so it needs less Disk space.
• The JRE can be downloaded/supported freely from https://www.java.com
• It includes the JVM , Core libraries and other additional components to run applications and applets written in Java.

JDK (Java Development Kit)

• It is a bundle of software that you can use to develop Java based applications.
• Java Development Kit is needed for developing java applications.
• The JDK needs more Disk space as it contains the JRE along with various development tools.
• The JDK can be downloaded/supported freely from https://www.oracle.com/technetwork/java/javase/downloads/
• It includes the JRE, set of API classes, Java compiler, Webstart and additional files needed to write Java applets and applications.