20145201 "Java Programming" first week of Study Summary (revision)

# 20145201 The first week of Java Program Design Study summary

# # Textbook Learning Content Summary

The beginning of everything is difficult, and finally began to learn java. Winter vacation time to see the teacher's request is indeed a bit of a panic, but this week opened books, from the book knowledge of the first line to learn, found not to think of it so difficult, as long as step by step, weekly have their own plans, and in accordance with the plan step by step completion, will eventually have their own small results.

1.1Java is more than just language

1. After many years of updating Java, the most recent version is Java SE8.
2. In the process of Java development, its application field is more and more wide, according to different levels of application development to distinguish between different application versions, the final three versions of Java (platform) are Java SE, Java EE, Java ME.

(1) The most basic of which is Java SE, which has four components: JVM, JRE, JDK, Java language.

To be able to run Java-authored programs, you must have a Java virtual machine JVM. The JVM is included in the Java execution Environment JRE, so you must install the JRE in order to run Java programs. If you want to develop Java programs, you must obtain JDK,JDK including the JRE and some of the tools needed during the development process.

(2) Java EE: Based on Java SE, it is suitable for developing distributed, multi-layered, component-based, web-based applications.

(3) Java ME: is the smallest version of the Java platform.

1.2 About JVM JRE JDK

(1) JVM: For Java programs, only one operating system, which is the JVM, is recognized. The JVM executable is the. Class document that implements the Java cross-platform through the JVM.

(2) Jre:java execution Environment.

(3) JDK: Provides a tool for compiling the program.

*tips command line mode

Dir: Lists the files and folders in the current directory

MD: Creating a Directory

RD: Deleting a directory

CD: Enter the specified directory

CD: Back to top level directory

Cd/: Go back to the root directory

Del: Delete Files

Exit: Exit DOS command line

Download install JDK, procedure

Configuring Environment variables

Write code and run

# # Problems and solutions in textbook learning

Most of the first half of the basic concept of the content has a lot of text content, not on the machine operation, feel more boring. It is easy to get started by combining video for practical operation.

# # Problems in code debugging and resolution process

1. File extension does not display properly

Can be displayed normally after setting

2. The system does not add after the code is compiled. Found in later checks, corrected.

# # Other

In writing Java code must be careful, such as the case, the problem of full-width half-width, try not to make mistakes. For example, this time, I added one less ".", although this time the code is relatively short, the inspection still took some time. If you write a longer program later, you still make this kind of low-level error, it will be very cumbersome to check. So must be careful and careful!! Attention to detail!! This time although only compiled a small program, their confidence has increased, I hope to continue to work hard ~

# # Learning Progress bar

| | Lines of code (new/cumulative) | Blog volume (Add/accumulate) | Learning time (NEW/cumulative) | Important growth |

| --------   | :----------------:|:----------------:|:---------------:  |:-----:|

| Target |   4500 Rows | 30 Articles |       400 hours | |

| First week |   200/200 | 1/2 |       15/15 | |

# # References

-[Java Learning Note (8th Edition)] (http://book.douban.com/subject/26371167/)

-[Java Learning Note (8th Edition) Learning Guide] (http://www.cnblogs.com/rocedu/p/5182332.html)

20145201 "Java Programming" first week of Study Summary (revision)