كيفية التكرار من خلال قائمة جافا؟ سبع (7) طرق للتكرار من خلال التكرار الحلقي في جافا

نشرت: 2020-01-01

كيفية التكرار من خلال قائمة جافا؟ سبع (7) طرق مختلفة للتكرار من خلال الحلقة في جافا

كيفية التكرار من خلال قائمة جافا؟ يوضح هذا البرنامج التعليمي استخدام ArrayList و Iterator و List.

هناك 7 طرق يمكنك من خلالها التكرار من خلال القائمة.

  1. حلقة For بسيطة
  2. حلقة For المحسنة
  3. التكرار
  4. مُعدل المصنف
  5. حائط اللوب
  6. Iterable.forEach () استخدام
  7. Stream.forEach () استخدام

مثال جافا:

أنت بحاجة إلى JDK 13 لتشغيل البرنامج أدناه حيث أن point-5 أعلاه تستخدم stream() .

void java.util.stream.Stream.forEach (إجراء المستهلك <؟ super String>) p يؤدي إلى تشويه إجراء لكل عنصر من عناصر هذا التدفق.

CrunchifyIterateThroughList.java
Java
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package crunchify . com . tutorials ;
 
import java . util . * ;
 
/**
* @author Crunchify.com
* How to iterate through Java List? Seven (7) ways to Iterate Through Loop in Java.
* 1. Simple For loop
* 2. Enhanced For loop
* 3. Iterator
* 4. ListIterator
* 5. While loop
* 6. Iterable.forEach() util
* 7. Stream.forEach() util
*/
 
public class CrunchifyIterateThroughList {
 
     public static void main ( String [ ] argv ) {
 
         // create list
         List <String> crunchifyList = new ArrayList <String> ( ) ;
 
         // add 4 different values to list
         crunchifyList . add ( "Facebook" ) ;
         crunchifyList . add ( "Paypal" ) ;
         crunchifyList . add ( "Google" ) ;
         crunchifyList . add ( "Yahoo" ) ;
 
         // Other way to define list is - we will not use this list :)
         List <String> crunchifyListNew = Arrays . asList ( "Facebook" , "Paypal" , "Google" , "Yahoo" ) ;
 
         // Simple For loop
         System . out . println ( "==============> 1. Simple For loop Example." ) ;
         for ( int i = 0 ; i < crunchifyList . size ( ) ; i ++ ) {
             System . out . println ( crunchifyList . get ( i ) ) ;
         }
 
         // New Enhanced For loop
         System . out . println ( "\n==============> 2. New Enhanced For loop Example.." ) ;
         for ( String temp : crunchifyList ) {
             System . out . println ( temp ) ;
         }
 
         // Iterator - Returns an iterator over the elements in this list in proper sequence.
         System . out . println ( "\n==============> 3. Iterator Example..." ) ;
         Iterator <String> crunchifyIterator = crunchifyList . iterator ( ) ;
         while ( crunchifyIterator . hasNext ( ) ) {
             System . out . println ( crunchifyIterator . next ( ) ) ;
         }
 
         // ListIterator - traverse a list of elements in either forward or backward order
         // An iterator for lists that allows the programmer to traverse the list in either direction, modify the list during iteration,
         // and obtain the iterator's current position in the list.
         System . out . println ( "\n==============> 4. ListIterator Example..." ) ;
         ListIterator <String> crunchifyListIterator = crunchifyList . listIterator ( ) ;
         while ( crunchifyListIterator . hasNext ( ) ) {
             System . out . println ( crunchifyListIterator . next ( ) ) ;
         }
 
         // while loop
         System . out . println ( "\n==============> 5. While Loop Example...." ) ;
         int i = 0 ;
         while ( i < crunchifyList . size ( ) ) {
             System . out . println ( crunchifyList . get ( i ) ) ;
             i ++ ;
         }
 
         // Iterable.forEach() util: Returns a sequential Stream with this collection as its source
         System . out . println ( "\n==============> 6. Iterable.forEach() Example...." ) ;
         crunchifyList . forEach ( ( temp ) - > {
             System . out . println ( temp ) ;
         } ) ;
 
         // collection Stream.forEach() util: Returns a sequential Stream with this collection as its source
         System . out . println ( "\n==============> 7. Stream.forEach() Example...." ) ;
         crunchifyList . stream ( ) . forEach ( ( crunchifyTemp ) - > System . out . println ( crunchifyTemp ) ) ;
     }
}

انتاج:

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============== > 1. Simple For loop Example .
Facebook
Paypal
Google
Yahoo
 
============== > 2. New Enhanced For loop Example . .
Facebook
Paypal
Google
Yahoo
 
============== > 3. Iterator Example . . .
Facebook
Paypal
Google
Yahoo
 
============== > 4. ListIterator Example . . .
Facebook
Paypal
Google
Yahoo
 
============== > 5. While Loop Example . . . .
Facebook
Paypal
Google
Yahoo
 
============== > 6. Iterable . forEach ( ) Example . . . .
Facebook
Paypal
Google
Yahoo
 
============== > 7. Stream . forEach ( ) Example . . . .
Facebook
Paypal
Google
Yahoo
 
Process finished with exit code 0