Analysis of Java large number BigInteger and BigDecimal class examples
BigInteger Class
In Java, there are many classes that need to be processed, such as the Integer class, but the Integer class also has an upper limit. Its maximum value is 2^31-1.
If we want to represent a larger number at this time, it cannot be represented by Integer, so Java provides the BigInteger class.
The numbers supported by the BigInteger class can be said to be infinite, and it supports integers of arbitrary precision, which means that it can accurately represent any value without loss.
I would also like to emphasize here that because the number type passed in is a character type, you cannot use - * /
corresponding to the method of using them when doing operations:
add(), subtract(), multiply(), divide()
There are also some common methods:
equals method. Compare
Code demonstration:
import java.math.BigInteger;
public class Demo01 {
public static void main(String[] args) {
BigInteger bigInteger1 = new BigInteger("2222222222222222222222222222222");
BigInteger bigInteger2 = new BigInteger("1111111111111111111111111111111");
System.out.println("bigInteger1大数为：" + bigInteger1);
System.out.println("bigInteger2大数为：" + bigInteger2);
System.out.println("两个大数相加：" + bigInteger1.add(bigInteger2));//加
System.out.println("两个大数相减：" + bigInteger1.subtract(bigInteger2));//减
System.out.println("两个大数相乘：" + bigInteger1.multiply(bigInteger2));//乘
System.out.println("两个大数相除：" + bigInteger1.divide(bigInteger2));//除
System.out.println("两个大数相比：" + bigInteger1.equals(bigInteger2));//equals进行比较
}
}
When doing division, if there are decimal places, the decimal places are intercepted here.
Of course, there are not only integer types, but also floating point types.
BigDecimal Class
Of course, the precision of the floating point type can also be as large as possible.
import java.math.BigDecimal;
public class Demo02 {
public static void main(String[] args) {
BigDecimal bigDecimal1 = new BigDecimal("12232423432432.53241234324");
BigDecimal bigDecimal2 = new BigDecimal("2.0");
System.out.println("bigDecimal1值： " + bigDecimal1);
System.out.println("bigDecimal2值： " + bigDecimal2);
System.out.println("加：" + bigDecimal1.add(bigDecimal2));
System.out.println("减：" + bigDecimal1.subtract(bigDecimal2));
System.out.println("乘：" + bigDecimal1.multiply(bigDecimal2));
System.out.println("除：" + bigDecimal1.divide(bigDecimal2));
}
}
In the BigDecimal method, it can also better solve the accuracy problem in the Java language (such as the problem that the result of 0.1x3 == 0.3 is false)
The problem of incomplete division in the BigDecimal class
But there is also a point that needs to be paid attention to when using BigDecimal (when it encounters a problem that cannot be divided, it will Choose the one that reports an error.)
So when doing division, just give it a truncation number.
Let’s look at a method first:
public BigDecimal divide(BigDecimal divisor, int scale, int roundingMode)
divisor - divisor.
scale - How many digits to keep after the decimal point
roundingMode - Select the rounding mode
So we can write it like this:
Rounding mode selection:
| Mode | Meaning |
|---|---|
| ROUND_CEILING | Get the number towards positive infinity |
| ROUND_DOWN | Get the number towards 0 |
| ROUND_FLOOR | Take the number toward negative infinity |
| ROUND_HALF_DOWN | Round down when encountering .5 |
| ROUND_HALF_UP | Rounding up when encountering .5 |
| ROUND_HALF_EVEN | Rounding up when encountering 5, look at the previous number, greater than 5 upwards, less than 5 upwards Down, equal to 5 and look forward. |
The above is the detailed content of Analysis of Java large number BigInteger and BigDecimal class examples. 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)
What is a deadlock in Java and how can you prevent it?
Aug 23, 2025 pm 12:55 PM
AdeadlockinJavaoccurswhentwoormorethreadsareblockedforever,eachwaitingforaresourceheldbytheother,typicallyduetocircularwaitcausedbyinconsistentlockordering;thiscanbepreventedbybreakingoneofthefournecessaryconditions—mutualexclusion,holdandwait,nopree
How to use Optional in Java?
Aug 22, 2025 am 10:27 AM
UseOptional.empty(),Optional.of(),andOptional.ofNullable()tocreateOptionalinstancesdependingonwhetherthevalueisabsent,non-null,orpossiblynull.2.CheckforvaluessafelyusingisPresent()orpreferablyifPresent()toavoiddirectnullchecks.3.Providedefaultswithor
Java Persistence with Spring Data JPA and Hibernate
Aug 22, 2025 am 07:52 AM
The core of SpringDataJPA and Hibernate working together is: 1. JPA is the specification and Hibernate is the implementation, SpringDataJPA encapsulation simplifies DAO development; 2. Entity classes map database structures through @Entity, @Id, @Column, etc.; 3. Repository interface inherits JpaRepository to automatically implement CRUD and named query methods; 4. Complex queries use @Query annotation to support JPQL or native SQL; 5. In SpringBoot, integration is completed by adding starter dependencies and configuring data sources and JPA attributes; 6. Transactions are made by @Transactiona
Java Cryptography Architecture (JCA) for Secure Coding
Aug 23, 2025 pm 01:20 PM
Understand JCA core components such as MessageDigest, Cipher, KeyGenerator, SecureRandom, Signature, KeyStore, etc., which implement algorithms through the provider mechanism; 2. Use strong algorithms and parameters such as SHA-256/SHA-512, AES (256-bit key, GCM mode), RSA (2048-bit or above) and SecureRandom; 3. Avoid hard-coded keys, use KeyStore to manage keys, and generate keys through securely derived passwords such as PBKDF2; 4. Disable ECB mode, adopt authentication encryption modes such as GCM, use unique random IVs for each encryption, and clear sensitive ones in time
![LOL Game Settings Not Saving After Closing [FIXED]](https://img.php.cn/upload/article/001/431/639/175597664176545.jpg?x-oss-process=image/resize,m_fill,h_207,w_330)
LOL Game Settings Not Saving After Closing [FIXED]
Aug 24, 2025 am 03:17 AM
IfLeagueofLegendssettingsaren’tsaving,trythesesteps:1.Runthegameasadministrator.2.GrantfullfolderpermissionstotheLeagueofLegendsdirectory.3.Editandensuregame.cfgisn’tread-only.4.Disablecloudsyncforthegamefolder.5.RepairthegameviatheRiotClient.
How to use the Pattern and Matcher classes in Java?
Aug 22, 2025 am 09:57 AM
The Pattern class is used to compile regular expressions, and the Matcher class is used to perform matching operations on strings. The combination of the two can realize text search, matching and replacement; first create a pattern object through Pattern.compile(), and then call its matcher() method to generate a Matcher instance. Then use matches() to judge the full string matching, find() to find subsequences, replaceAll() or replaceFirst() for replacement. If the regular contains a capture group, the nth group content can be obtained through group(n). In actual applications, you should avoid repeated compilation patterns, pay attention to special character escapes, and use the matching pattern flag as needed, and ultimately achieve efficient
Edit bookmarks in chrome
Aug 27, 2025 am 12:03 AM
Chrome bookmark editing is simple and practical. Users can enter the bookmark manager through the shortcut keys Ctrl Shift O (Windows) or Cmd Shift O (Mac), or enter through the browser menu; 1. When editing a single bookmark, right-click to select "Edit", modify the title or URL and click "Finish" to save; 2. When organizing bookmarks in batches, you can hold Ctrl (or Cmd) to multiple-choice bookmarks in the bookmark manager, right-click to select "Move to" or "Copy to" the target folder; 3. When exporting and importing bookmarks, click the "Solve" button to select "Export Bookmark" to save as HTML file, and then restore it through the "Import Bookmark" function if necessary.
!['Java is not recognized' Error in CMD [3 Simple Steps]](https://img.php.cn/upload/article/001/431/639/175588500160220.jpg?x-oss-process=image/resize,m_fill,h_207,w_330)
'Java is not recognized' Error in CMD [3 Simple Steps]
Aug 23, 2025 am 01:50 AM
IfJavaisnotrecognizedinCMD,ensureJavaisinstalled,settheJAVA_HOMEvariabletotheJDKpath,andaddtheJDK'sbinfoldertothesystemPATH.RestartCMDandrunjava-versiontoconfirm.
