Exception in thread "main" java.lang.NullPointerException at java.util.ArrayDeque.addLast(ArrayDeque.java:249) at java.util.ArrayDeque.add(ArrayDeque.java:423) at com.javaTpoint.JavaCollectionContainsAllExample2.main(JavaCollectionContainsAllExample2.java:13) 例子3 importjava.util.ArrayDeque;importjava....
输出: Exception in thread "main" java.lang.NullPointerException at java.util.ArrayDeque.addLast(ArrayDeque.java:249) at java.util.ArrayDeque.add(ArrayDeque.java:423) at com.javaTpoint.JavaCollectionRemoveExample3.main(JavaCollectionRemoveExample3.java:13)...
The iterator () method returns an iterator over the elements in this collection. Example 1 importjava.util.Collection; importjava.util.Iterator; importjava.util.concurrent.ConcurrentLinkedQueue; publicclassJavaCollectionIteratorExample1 { staticinti =1; ...
at java.util.concurrent.ConcurrentLinkedQueue.offer(ConcurrentLinkedQueue.java:327) at java.util.concurrent.ConcurrentLinkedQueue.add(ConcurrentLinkedQueue.java:297) at com.javaTpoint.JavaCollectionAddExample4.main(JavaCollectionAddExample4.java:13) If any of the specified element in this queue is nul...
输出: Exception in thread "main" java.lang.NullPointerException at java.util.concurrent.ConcurrentLinkedQueue.toArray(ConcurrentLinkedQueue.java:638) at com.javaTpoint.JavaCollectionToArrayExample4.main(JavaCollectionToArrayExample4.java:12) 相关...
Exception in thread "main" java.lang.NullPointerException at java.util.ArrayDeque.addLast(ArrayDeque.java:249) at java.util.ArrayDeque.add(ArrayDeque.java:423) at com.javaTpoint.JavaCollectionContainsAllExample2.main(JavaCollectionContainsAllExample2.java:13) ...
publicclassJavaCollectionContainsExample2 { publicstaticvoidmain(String[] args) { Scanner scanner=newScanner(System.in); Collection<Integer> queue =newConcurrentLinkedQueue<Integer>(); queue.add(2); System.out.println("Q. Enter smallest even prime no"); ...
at java.util.concurrent.ConcurrentLinkedQueue.offer(ConcurrentLinkedQueue.java:327) at java.util.concurrent.ConcurrentLinkedQueue.add(ConcurrentLinkedQueue.java:297) at com.javaTpoint.JavaCollectionRemoveAllExample3.main(JavaCollectionRemoveAllExample3.java:13)...
Example 1import java.util.Collection; import java.util.concurrent.LinkedBlockingDeque; public class JavaCollectionClearExample1 { public static void main(String[] args) { Collection<Integer> collection = new LinkedBlockingDeque<Integer>(); collection.add(23); collection.add(123); collection.add(56...
at java.util.AbstractCollection.retainAll(AbstractCollection.java:405) at com.javaTpoint.JavaCollectionRetainAllExample4.main(JavaCollectionRetainAllExample4.java:17) Java Collection retainAll() Method The retainAll() method of Java Collection class retains or keeps only the elements in this collection...