java--Development Environment Construction

Installing the Java Environment

As every Java enthusiast, whether it's development or testing, wants to start a Java programming journey, there needs to be a tool called "工欲善其事, its prerequisite." The inside is the Java tool--JDK that we are going to install.

Classification of Java

Java is divided into J2SE, EE and J2ME three different platform versions, namely Standard Edition (Java 2 Platform, Standards Edition), Enterprise Edition (Java 2 Platform Edition) and mini-version (Java 2 Platform, Micro Edition). Starting with Java 1.5 (or Java 5.0), they are called Java SE, Java EE, and Java ME.

Java Development history

May 23, 1995, the birth of the Java language [1];

January 1996, the first jdk-jdk1.0 was born;

In April 1996, 10 of the most important operating system vendors affirmed that Java technology would be embedded in their products;

In September 1996, about 83,000 Web pages were created using Java technology;

February 18, 1997, JDK1.1 released;

April 2, 1997, the JavaOne meeting, the participation of more than 10,000 people, creating a record of the world's similar conference size;

In September 1997, Javadeveloperconnection community members exceeded 100,000;

In February 1998, JDK1.1 was downloaded more than 2,000,000 times;

December 8, 1998, JAVA2 Enterprise platform of the June 1999, Sun Company released Java three versions: standard, Enterprise and mini-edition;

May 8, 2000, JDK1.3 released;

May 29, 2000, JDK1.4 released;

Nokia announced June 5, 2001 that it will sell 100 million Java-enabled handsets by 2003;

September 24, 2001, j2ee1.3 released;

February 26, 2002, j2se1.4 released, since the Java computing capacity has been significantly improved;

September 30, 2004 18:00pm,j2se1.5 released as another milestone in the development of the Java language. To indicate the importance of this version, j2se1.5 renamed Java SE 5.0;

In June 2005, the JavaOne conference was held and Sun disclosed Java SE 6. At this point, various versions of Java have been renamed to remove the number "2": the name of the Java ee,j2se renamed to Java Se,j2me renamed Java ME;

December 2006, Sun Company released JRE6.0;

April 7, 2009 Google APP engine started to support Java;

Oracle acquires Sun for $7.4 billion on April 20, 2009. Access to Java Copyright;

In November 2010, because Oracle was unfriendly to the Java community, Apache threatened to quit JCP;

July 28, 2011, Oracle releases the official version of Java 7.0;

March 19, 2014, Oracle releases the official version of Java 8.0.

Java Development and runtime Environment (Java SE):

1. Download Jdk/jre:

The first is to download the JDK:

Http://www.oracle.com/technetwork/java/javase/downloads/index.html

Download good double-click Install. You can choose the default installation path C:\Program files\java\jdk1.8.0_65\, or you can define your own path.

After installation, the C-drive program Files\java appears below two folder JDK and JRE,JDK (Java development ToolKit) Java Development Kit. The JDK is the core of the entire Java, including the Java Runtime Environment, a stack of Java tools (JAVAC/JAVA/JDB, etc.) and a Java-based class library (that is, the Java API includes Rt.jar). JRE (Java runtime enviromental) Java Runtime Environment. That is what we call the Java platform, all Java programs must be under the JRE to run. Includes JVM and Java core class libraries and support files. It does not include development tools-compilers, debuggers, and other tools-compared to the JDK. For more detailed introduction can go to self-Baidu. The next step is to configure the environment variables. My Computer Right-click menu---> Properties---> Advanced---> Environment variables---> System variables--New

User variable name: Java_home variable Value: C:\Program files\java\jdk1. 8. 0_65 system Variable Name: Calss_path variable value:.; %java_home%\bin;%java_home%\lib\dt.jar;%java_home%\lib\tools.jar

Locate the PATH variable name, "edit" to add:

system Variable Name: PATH variable value:%java_home%\bin;%java_home%\jre\bin;

Some friends according to this configuration may be reported Javac is not internal or external commands, then you can also set up the JDK installed bin directory directly under Path.

system Variable Name: PATH variable value: C:\Program files\java\jdk1. 8.0_65\bin;

The Java development environment is installed here, so let's test it.

Open cmd,java–version to view the JDK version

Then enter Java

Re-enter Javac

The Java command can run a class file byte code.

Javac command to compile Java source files into a class bytecode file

I wrote a Helloworld.java source file in the D-Disk workspace directory, and we compiled it with the cmd javac command.

So far, the Java development environment has been installed.

download Java programming tool Eclipse

: http://www.eclipse.org/downloads/

Download good after the direct decompression, set up a good workspace can be used. With Eclipse, there is no need to go to the cmd command javac the source file and then Java to compile it. Write code debugging run directly in Eclipse. In eclipse, for example, there is a simplest Java program Helloworld.java.

Eclipse is powerful and will later write some tips and shortcuts for using Eclipse tools.

java--Development Environment Construction