What does the java development package jdk contain?

JDK: Java Development ToolKit (Java Development Tool Kit). JDK is the core of the entire JAVA, including the Java Runtime Environment (Java Runtime Envirnment), a bunch of Java tools (javac/java/jdb, etc.) and Java basic class libraries (that is, Java API including rt.jar).

The most mainstream JDK is the JDK released by Sun. In addition to Sun, there are many companies and organizations that have developed their own JDK, such as foreign countries. IBM has developed its own JDK, and domestic Taobao has also developed its own JDK. Each organization develops its own JDK in order to improve in certain aspects to adapt to its own needs. For example, IBM's JDK is said to have the highest operating efficiency. Much higher than SUN's JDK. But no matter what, we still need to master the basic Sun JDK first.

JDK is a java development tool kit. There are six folders, some description files, and a src compressed file under its installation directory. The four folders bin, include, lib, and jre work, and demo and sample are some examples. It can be seen that JDK contains JRE, and JRE contains JVM.

bin: The most important thing is the compiler (javac.exe)

include: java and Header file for JVM interaction

lib: class library

jre:java running environment (note: the bin, lib folders here and The bin and lib in jre are different)

In generalJDK is used for the development of java programs, while jre can only run classes without compiling functions.

JDK is provided for Java developers to use, which includes Java development tools, including JRE. So after installing the JDK, there is no need to install the JRE separately. The development tools include compilation tools (javac.exe) packaging tools (jar.exe), etc.

There is a jre directory under the JDK installation directory, which contains two folders bin and lib. Here you can It is believed that what is in bin is jvm, and what is in lib is the class library needed for jvm to work. The combination of jvm and lib is called jre.

The above is the detailed content of What does the java development package jdk contain?. For more information, please follow other related articles on the PHP Chinese website!