In object-oriented programming methods, encapsulation (English: Encapsulation) refers to a method of partially packaging and hiding the implementation details of an abstract functional interface .
Encapsulation can be thought of as a protective barrier that prevents the code and data of the class from being randomly accessed by code defined by the external class. ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? (Recommended learning: java course)
To access the code and data of this class, strict interface control must be passed.
The main function of encapsulation is that we can modify our own implementation code without modifying the program fragments that call our code.
Proper encapsulation can make the program code easier to understand and maintain, and also enhance the security of the program code.
Advantages of encapsulation
1. Good encapsulation can reduce coupling.
2. The structure inside the class can be modified freely.
3. Member variables can be more precisely controlled.
4. Hide information and implement details.
Steps to implement Java encapsulation
1. Modify the visibility of the property to restrict access to the property (generally restricted to private), for example:
public class Person { private String name; private int age; }
In this code, the name and age attributes are set to private, which can only be accessed by this class and not by other classes, thus hiding the information.
2. Provide external public method access to each value attribute, that is, create a pair of assignment methods for access to private attributes, for example:
public class Person{ private String name; private int age; public int getAge(){ return age; } public String getName(){ return name; } public void setAge(int age){ this.age = age; } public void setName(String name){ this.name = name; } }
The this keyword is used to resolve the conflict of the same name between the instance variable (private String name) and the local variable (name variable in setName(String name)).
The above is the detailed content of Understand what encapsulation is in java. For more information, please follow other related articles on the PHP Chinese website!

Hot AI Tools

Undress AI Tool
Undress images for free

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

The settings.json file is located in the user-level or workspace-level path and is used to customize VSCode settings. 1. User-level path: Windows is C:\Users\\AppData\Roaming\Code\User\settings.json, macOS is /Users//Library/ApplicationSupport/Code/User/settings.json, Linux is /home//.config/Code/User/settings.json; 2. Workspace-level path: .vscode/settings in the project root directory

To correctly handle JDBC transactions, you must first turn off the automatic commit mode, then perform multiple operations, and finally commit or rollback according to the results; 1. Call conn.setAutoCommit(false) to start the transaction; 2. Execute multiple SQL operations, such as INSERT and UPDATE; 3. Call conn.commit() if all operations are successful, and call conn.rollback() if an exception occurs to ensure data consistency; at the same time, try-with-resources should be used to manage resources, properly handle exceptions and close connections to avoid connection leakage; in addition, it is recommended to use connection pools and set save points to achieve partial rollback, and keep transactions as short as possible to improve performance.

DependencyInjection(DI)isadesignpatternwhereobjectsreceivedependenciesexternally,promotingloosecouplingandeasiertestingthroughconstructor,setter,orfieldinjection.2.SpringFrameworkusesannotationslike@Component,@Service,and@AutowiredwithJava-basedconfi

itertools.combinations is used to generate all non-repetitive combinations (order irrelevant) that selects a specified number of elements from the iterable object. Its usage includes: 1. Select 2 element combinations from the list, such as ('A','B'), ('A','C'), etc., to avoid repeated order; 2. Take 3 character combinations of strings, such as "abc" and "abd", which are suitable for subsequence generation; 3. Find the combinations where the sum of two numbers is equal to the target value, such as 1 5=6, simplify the double loop logic; the difference between combinations and arrangement lies in whether the order is important, combinations regard AB and BA as the same, while permutations are regarded as different;

fixture is a function used to provide preset environment or data for tests. 1. Use the @pytest.fixture decorator to define fixture; 2. Inject fixture in parameter form in the test function; 3. Execute setup before yield, and then teardown; 4. Control scope through scope parameters, such as function, module, etc.; 5. Place the shared fixture in conftest.py to achieve cross-file sharing, thereby improving the maintainability and reusability of tests.

java.lang.OutOfMemoryError: Javaheapspace indicates insufficient heap memory, and needs to check the processing of large objects, memory leaks and heap settings, and locate and optimize the code through the heap dump analysis tool; 2. Metaspace errors are common in dynamic class generation or hot deployment due to excessive class metadata, and MaxMetaspaceSize should be restricted and class loading should be optimized; 3. Unabletocreatenewnativethread due to exhausting system thread resources, it is necessary to check the number of threads, use thread pools, and adjust the stack size; 4. GCoverheadlimitexceeded means that GC is frequent but has less recycling, and GC logs should be analyzed and optimized.

Use classes in the java.time package to replace the old Date and Calendar classes; 2. Get the current date and time through LocalDate, LocalDateTime and LocalTime; 3. Create a specific date and time using the of() method; 4. Use the plus/minus method to immutably increase and decrease the time; 5. Use ZonedDateTime and ZoneId to process the time zone; 6. Format and parse date strings through DateTimeFormatter; 7. Use Instant to be compatible with the old date types when necessary; date processing in modern Java should give priority to using java.timeAPI, which provides clear, immutable and linear

TheJVMenablesJava’s"writeonce,runanywhere"capabilitybyexecutingbytecodethroughfourmaincomponents:1.TheClassLoaderSubsystemloads,links,andinitializes.classfilesusingbootstrap,extension,andapplicationclassloaders,ensuringsecureandlazyclassloa
