20165103 2017-2018-2 "Java Program Design" 3rd week Study summary Textbook study summary
- Learn about several stages of programming language development: for machine language (e.g. assembly language)-for procedural languages (e.g. C)-object oriented language (e.g. Java)
- The object-oriented language has the characteristics of encapsulation, inheritance and polymorphism.
- The Declaration and basic structure of classes and methods, classes have methods and variables, variables are divided into member variables and local variables, member variables have default values, but local variables do not have a default value.
- Objects are created and objects are manipulated by their own variables and methods
. , objects can be referenced, and values can be passed by reference.
- Classes can be combined with classes.
- The characteristics of instance variables and class variables, instance methods, and class methods.
- Overloading of methods, conditional on the same method name, the number of arguments or the corresponding type of the parameter, but also to avoid ambiguity.
- About
this关键字 the study.
- The expansion of knowledge about the package.
import语句Use, note that when used, a class with a package name cannot use a class without a package name.- Four access rights: Private variables private methods (private), shared variables and common methods (public), friendly variables and friendly methods (not added), protected member variables, and methods (protected).
- As for the encapsulation of the basic class, this part is mainly about the introduction of several basic types of method packages.
- About jar files are packaged in use.
Problems in teaching materials learning and the solving process
- Issue 1: The use of custom packages is not well understood when learning to introduce classes in a custom package.
- Problem 1 Solution: For the two methods provided in the further research book, the first method needs to be set for the Classpath path, the second method is to put the custom package directly into a folder, then the program is called with an import statement, which is essentially the equivalent of creating a class library.
- Question 2: The specific use of this statement is not clear, the sense that this can often be omitted.
- Problem 2 Solution: A preliminary understanding is that by using the this statement, an object invokes a method and can invoke the method with this in the method.
- ...
Problems in code debugging and the resolution process
- Issue 1: In the debug of Example4_1, no output is found
- Problem 1 Solution: It was later discovered that because 4_1 is a class of 4_3, it does not include an output statement.
Code Hosting
(run result of statistics.sh script)
Last week's summary of the wrong quiz
- Wrong question 1 and reason, understand the situation
- Wrong question 2 and reason, understand the situation
- ...
Learning progress Bar
| |
Code lines (new/cumulative) |
Blog volume (Add/accumulate |
Learning Time (new/cumulative) |
important growth |
| target |
5000 Line |
30 |
400 hours |
|
| first week |
100/100 |
2 /2 |
10/10 |
|
| second week |
200/300 |
1/3 |
15/25 |
|
| third week |
189/489 |
1/4 |
20/45 |
|
Planned study time: 25 hours
Actual learning time: 20 hours
- Improved situation:
This week's learning content is a bit more, need to understand more places, many places the correlation needs to be more detailed analysis, using the book and video combination of methods. Overall the progress from learning time, but still feel the lack of time, at the same time, next week's computer secondary examination will need more time. For the Java learning also need to further accelerate, and further strengthen the Code on the computer practical practice.
Resources
20165103 2017-2018-2 "Java Programming" 3rd Week study Summary
