because my Java has always been a bad level, a freshman when only 60 points. So near graduation, I chose to rebuild Java, these days are slowly reviewing Java, will be in the blog to record some Java knowledge, not for how many people see, only hope that their own harvest.
First,java introduction: in 1995, Sun launched the company. in 2009, Oracle Corporation acquired Sun.
Java SE, Standard version. Java EE, Enterprise Edition, for development of enterprise-class applications. Java ME, embedded development, such as Android-based mobile games.
Introduction to Java Related concepts:
1. JVM (Java Virtual machine) Java VM: Java Development is the first to write the suffix. Java source code files, source files through the compiler , programming binary to the end of the. Class bytecode file , bytecode files are platform-independent. To execute the bytecode, an interpreter is required to interpret the translation. The JVM contains the interpreter, so this is the Java cross-platform capital. 2. JDK: JDK (Java Development Kit) is the Java language Software Development Kit3. JRE(Java Runtime Environment,java Runtime Environment), a collection of environments necessary to run Java programs, including the JVM standard implementation and the Java Core Class library
Second, the Java development environment to build(1) Download the new version of the JDK and install it. It is not recommended to install under the default Program Files folder, as there may be problems with spaces inside the path. after installation, enter the directory of the JDK installation, and CTRL + C after the path is checked for the current path(2) Configure environment variables. Computer Properties Advanced system settings environment variables. A total of two variables to be added, respectively, are Java_home and classpath. first, in the system variable, click New, add variable java_home, the variable value CTRL + V to copy the next JDK path. Such as:Then, similarly, the new variable classpath, the value of the variable is:.; C:\Java\jdk1.8.0_25\lib; (note here that there is a point, which represents the current path, this point must not be forgotten) here the second path is the Lib folder of the JDK installation directory, you can modify it according to your own path..
The next step is to modify the variables. Locate the path variable in the system variable, copy the JDK down Bin directory path to the front of the path variable and separate it with a semicolon.
In order to verify that our environment variables are configured correctly, we win+r, enter CMD, and bring up the command prompt. Entering Java and javac at the command prompt, if prompted for Java usage, indicates that our configuration was successful. To say this, Javac is used to compile the source code program into a bytecode file, Java is used to execute bytecode files and execution does not specify a file suffix.
This article refers to the Web Java Video tutorial, special thanks.
2014.12.26 22:02by mr.losers
Java Introduction and development environment building
