What are the eight basic data types of Java?-JavaBase-php.cn

Home

Java

JavaBase

What are the eight basic data types of Java?

青灯夜游

Nov 02, 2020 pm 01:41 PM

java type of data

The eight basic data types of Java are: 1. Integer type byte, short, int, long; 2. Character type char; 3. Floating point type float, double; 4. Boolean type boolean.

What are the eight basic data types of Java?

(Recommended tutorial: java introductory tutorial)

Since the release of Java, the basic data types have been in the Java language Part of them are byte, short, int, long, char, float, double, boolean.

What are the eight basic data types of Java?

##where:

Integer type: byte, short, int, long

Character type: char

Floating point type: float, double

Boolean type: boolean

1. Integer type

Integer data in Java are signed numbers, that is, the first bit is 0, which means a positive integer. A bit of 1 represents a negative integer. In computers, negative numbers are represented by complements, so how are complements calculated?

(Recommended video tutorial:

java video tutorial)

Complement code = negate the source code by 1;

For example:
22, represented in the computer as 00010110,
-22, negated: 11101001, plus 1: 11101010

byte

byte is an integer type in Java. The length is 1 byte and 8 bits. The value is 10000000 (-128) to 01111111 (127). The default value of variable initialization is 0. Packaging Class Byte

short

#short is an integer type in Java, with a length of 2 bytes and 16 bits, and a value of 10000000 00000000 (-32768) To 01111111 11111111 (32767), the default value of variable initialization is 0, and the packaging class Short

int

int belongs to the integer type in Java, The length is 4 bytes and 32 bits, and the value is -2^31 (-2,147,483,648) to 2^31-1 (2,147,483,647). The default value of variable initialization is 0, packaging class Integer

long

long is an integer type in Java, with a length of 8 bytes and 64 bits, and a value of -2^63 (-9,223,372,036,854,775,808) to 2^63-1 (9,223,372,036,854,775,8087). The default value of variable initialization is 0 or 0L, and the packaging class Long

2. Floating point type

Floating point data in Java cannot be converted into binary Direct representation, but an approximate data representation for real numbers, which follows the IEEE 754 standard

float

float belongs to Java Floating point type, also called single-precision floating point type, length is 4 bytes and 32 bits, variable initialization default value is 0.0f, packaging class Float

1. float structure

Contains three parts:

Sign bit, exponent bit, mantissa bit

##Length1bit8bit23bitExplanation0 represents a positive number, 1 represents a negative numberThe format is ,

2. Float value

Formal form:

Informal form:

It is easy according to the above formula The calculated value range of float is:

(minimum value, when the sign bit S is 1 and the exponent bit E is 255)

(Maximum value, when the sign bit S is 0 and the exponent bit E is 255)

can get the approximate data in between.

Note: Depending on the different values of the exponent bit and the mantissa bit, there are many special cases, such as NAN, positive infinity, and negative infinity, but they are basically not used in daily life, so we will not go into details here; At the same time, because it is an approximate value, the amount cannot be expressed. It is recommended to use BigDecimal

double

double is a floating point in Java. type, also called double-precision floating-point type, with a length of 8 bytes and 64 bits. The default variable initialization value is 0.0d. The packaging class Double

1. The double structure

contains Three parts: Sign bit, exponent bit, mantissa bit

##Sign bit (S)	Exponent bit (E)	Mantissa bit(M)

	, E Value range: (0,255), exponent value: (	is in the form of 1.M or 0.M. Among them, when E=0, take 1.M, which is called the normal form. When E! = 0, take 0.M, which is called the informal form

##Sign bit (S)Exponent bit (E)Mantissa bit(M)##LengthExplanation, E value range : (0,2047), the exponent bit value: (2. Double value


1bit	11bit	52bit
0 represents a positive number, 1 represents a negative number	The format is	, ) is in the form of 1.M or 0.M. Among them, when E=0, take 1.M, which is called the normal form. When E! = 0, take 0.M, which is called the informal form

Formal form:

Informal form:

According to the above formula, it is easy to calculate the value range of double:

(minimum value, when the sign bit S is 1. The exponent bit E is 2047)

(maximum value, when the sign bit S is 0, the exponent bit E is 2047)
can get the approximate data in between.

Note: Depending on the different values of the exponent bit and the mantissa bit, there are many special cases, such as NAN, positive infinity, and negative infinity, but they are basically not used in daily life, so we will not go into details here; At the same time, because it is an approximate value, the amount cannot be expressed. It is recommended to use BigDecimal

## to express the amount. Three. Character type

char

Char is a character type in Java, occupies 2 bytes and 16 bits. It can assign single characters and integer values. There is no default value for variable initialization, and it is a packaging class Character.

For example:

char a = 'a';

char a = '中';

char a = 12; // Value range 0~65536, because the char type has corresponding values in ASCII character encoding, and can be directly operated and output the corresponding characters in the character table

4. Boolean type

boolean

The JVM does not provide boolean-specific bytecode instructions, and boolean type data is passed through After compilation, it will be represented by the int type in the JVM. At this time, the boolean data is 4 bytes and 32 bits, and the boolean array will be encoded into a byte array of the Java virtual machine. At this time, each boolean data occupies 8 bits per byte.

--Java Virtual Machine Specification

There are only two values true, false, and the default value of variable initialization is false

For more programming-related knowledge, please visit:

Programming Teaching

! !

The above is the detailed content of What are the eight basic data types of Java?. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress images for free

Clothoff.io

AI clothes remover

Video Face Swap

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

Hot Article

Assassin's Creed Shadows: Seashell Riddle Solution

1 months ago By DDD

What's New in Windows 11 KB5054979 & How to Fix Update Issues

3 weeks ago By DDD

Where to find the Crane Control Keycard in Atomfall

1 months ago By DDD

How to fix KB5055523 fails to install in Windows 11?

2 weeks ago By DDD

InZoi: How To Apply To School And University

3 weeks ago By DDD

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)

Hot Topics

Where is the login entrance for gmail email?

7767

Java Tutorial

1644

CakePHP Tutorial

1399

Laravel Tutorial

1293

PHP Tutorial

1234

Related knowledge

Java Spring Interview Questions Aug 30, 2024 pm 04:29 PM

In this article, we have kept the most asked Java Spring Interview Questions with their detailed answers. So that you can crack the interview.

Break or return from Java 8 stream forEach? Feb 07, 2025 pm 12:09 PM

Java 8 introduces the Stream API, providing a powerful and expressive way to process data collections. However, a common question when using Stream is: How to break or return from a forEach operation? Traditional loops allow for early interruption or return, but Stream's forEach method does not directly support this method. This article will explain the reasons and explore alternative methods for implementing premature termination in Stream processing systems. Further reading: Java Stream API improvements Understand Stream forEach The forEach method is a terminal operation that performs one operation on each element in the Stream. Its design intention is

PHP: A Key Language for Web Development Apr 13, 2025 am 12:08 AM

PHP is a scripting language widely used on the server side, especially suitable for web development. 1.PHP can embed HTML, process HTTP requests and responses, and supports a variety of databases. 2.PHP is used to generate dynamic web content, process form data, access databases, etc., with strong community support and open source resources. 3. PHP is an interpreted language, and the execution process includes lexical analysis, grammatical analysis, compilation and execution. 4.PHP can be combined with MySQL for advanced applications such as user registration systems. 5. When debugging PHP, you can use functions such as error_reporting() and var_dump(). 6. Optimize PHP code to use caching mechanisms, optimize database queries and use built-in functions. 7

PHP vs. Python: Understanding the Differences Apr 11, 2025 am 12:15 AM

PHP and Python each have their own advantages, and the choice should be based on project requirements. 1.PHP is suitable for web development, with simple syntax and high execution efficiency. 2. Python is suitable for data science and machine learning, with concise syntax and rich libraries.

Java Program to Find the Volume of Capsule Feb 07, 2025 am 11:37 AM

Capsules are three-dimensional geometric figures, composed of a cylinder and a hemisphere at both ends. The volume of the capsule can be calculated by adding the volume of the cylinder and the volume of the hemisphere at both ends. This tutorial will discuss how to calculate the volume of a given capsule in Java using different methods. Capsule volume formula The formula for capsule volume is as follows: Capsule volume = Cylindrical volume Volume Two hemisphere volume in, r: The radius of the hemisphere. h: The height of the cylinder (excluding the hemisphere). Example 1 enter Radius = 5 units Height = 10 units Output Volume = 1570.8 cubic units explain Calculate volume using formula: Volume = π × r2 × h (4

PHP vs. Python: Core Features and Functionality Apr 13, 2025 am 12:16 AM

PHP and Python each have their own advantages and are suitable for different scenarios. 1.PHP is suitable for web development and provides built-in web servers and rich function libraries. 2. Python is suitable for data science and machine learning, with concise syntax and a powerful standard library. When choosing, it should be decided based on project requirements.

PHP vs. Other Languages: A Comparison Apr 13, 2025 am 12:19 AM

PHP is suitable for web development, especially in rapid development and processing dynamic content, but is not good at data science and enterprise-level applications. Compared with Python, PHP has more advantages in web development, but is not as good as Python in the field of data science; compared with Java, PHP performs worse in enterprise-level applications, but is more flexible in web development; compared with JavaScript, PHP is more concise in back-end development, but is not as good as JavaScript in front-end development.

Create the Future: Java Programming for Absolute Beginners Oct 13, 2024 pm 01:32 PM

Java is a popular programming language that can be learned by both beginners and experienced developers. This tutorial starts with basic concepts and progresses through advanced topics. After installing the Java Development Kit, you can practice programming by creating a simple "Hello, World!" program. After you understand the code, use the command prompt to compile and run the program, and "Hello, World!" will be output on the console. Learning Java starts your programming journey, and as your mastery deepens, you can create more complex applications.

See all articles