The difference between JDK and Jre,java SE and Java EE and Java Me

The JDK, Java Development Kit, is intended for developers and provides a Java development environment and a running environment.

The JRE, the Java runtime enviroment, is a Java-oriented program user.

The JVM, the Java Virtul Machine.java virtual machine, is the most central part of Java implementation across platforms.

Overall relationship: JDK contains jre,jre containing JVM

After installing the JDK, there are two JRE computers, because almost all the tools in the JDK are written in Java, to use the tools attached to the JDK to develop Java programs, you must attach a set of JRE.

Java. EXE distinguishes which JRE to use. First look at their own directory there is no JRE, there is no JRE under the parent directory; Query the registry [Hkey_local_machine\software\javasoft\java Runtime Environment].

All Java programs are compiled into. class files that can be executed on the JVM. However, it is necessary to invoke the class library when executing the class file Lib,lib exists in the JRE (the JRE is equivalent to the JVM and the class library is Lib). What really works in the JDK in Java is Bin,include,lib,jre bin: the main compiler (Javac.exe), Include:java and JVM interaction header files, Lib: Class library, Jre:java runtime environment.

Other Ides, such as Eclipse, idea, and so on, have their own compilers instead of their own in the JDK Bin directory, so at installation you will find that they only require you to select the JRE path to be OK.

Java SE to do console program

Jave ee to do the web and so on with server program

Java me to do mobile end program