201521123035 the first week of Java Program Design Study summary

1. Summary of this week's study

This week we learned some of the history of Java from birth to today, and learned about Java's compilation process in CMD through a teacher's classroom presentation. Then I learned about JDK,JRE,JVM.

2. Written work

1. Why are Java programs running across platforms? What are the steps to execute a Java program? (please write in your own language)

Because Java executes on the JVM and the JVM is architected on a variety of operating system platforms, Java can run across platforms.

Step: Take the file name Hello for example, stored in D, open cmd, enter D, and then input Javac Hello.java finally lost Java Hello

2. What is the difference between a JDK?JDK,JRE,JVM?

The JDK is a tool program that provides a compiler program. JDK is compiled Java program, JRE is execute Java program, JRE contains Java SE API and JVM.

3.java HelloWorld Command, what does this parameter refer to in HelloWorld? Is it a file name? What is the meaning of this command?

This parameter refers to the class name, and the meaning of the command is the meaning of the execution.

What is the use of 4.path variables? What is the use of classpath variables?

By setting the path information for the tool in path, the system can find the instructions to execute in path.

The JVM will find out if there is a corresponding class document based on the CLASSPATH path order.

5. What is the difference between writing a program in Java and running a program and running it with the C language, and the intermediate and target files that are generated?

Java first is *.java, compiled is *.class, C is the beginning of *.c, compiled is *.obj.

What are the 3 app versions of the 6.Java language? What is the relationship between versions?

There are three versions of Javase, Java EE, javame.

Javase is divided into Jvm,jre,jdk,java,javaee based on Javase, Javame is the smallest version of the Java platform.

What is the difference between a 7.Oracle jdk and an open JDK?

The former source code can be used for personal research purposes, prohibit any commercial use, the latter allows commercial use.

What are the main applications of 8.Java? What are your goals and expectations in this course?

Web Development, Android development

The goal is to be able to pass the exam, the farther goal is to be able to make a Web page or a simple small game.

3. Using the code cloud to manage Java code

4. Experimental summary

This experiment harvest very big, feel oneself still have a lot of place that do not understand, need to the classmate teacher in time consult. Because it's the first time you've touched Java, many new concepts are familiar and mastered, and when installing Eclipse, remember to configure environment variables.

201521123035 the first week of Java Program Design Study summary