arraylist implementation in java source code

740 * returned by an initial call to {@link ListIterator#next next}. 668 for (; r < size; r++) 277 * in this list, or -1 if this list does not contain the element. 49 * 790 public E next() {, 791 checkForComodification(); 168 } 496 if (numMoved > 0) 373 849 throw new NoSuchElementException(); 917 185 // overflow-conscious code 582 * toIndex < fromIndex}) 606 (If 357 public T[] toArray(T[] a) { 193 * Attempts to allocate larger arrays may result in 948 return oldValue; 1093 cursor = i + 1; 614 164 modCount++; 440 * @param index the index of the element to be removed. 55 * If multiple threads access an ArrayList instance concurrently, 192 * Some VMs reserve some header words in an array. 597 * Checks if the given index is in range. 966 this.modCount = parent.modCount; In Array, we have to provide the size at the time of initialization but that is not required for ArrayList. 578 * {@code toIndex} is out of range (A structural modification is 1129 throw new ConcurrentModificationException(); Here is the code from the ArrayList class in Java. 1016 int expectedModCount = ArrayList.this.modCount; 337 * allocated with the runtime type of the specified array and the size of 555 158 /** This site uses Akismet to reduce spam. If you continue to use this site we will assume that you are happy with it. 586 int numMoved = size - toIndex; 628 * @param c collection containing elements to be removed from this list 862 try { 1059 329 return Arrays.copyOf(elementData, size); ArrayList Implementation In Java - Java Code Korner ArrayList Implementation In Java Array List is a class present in java.util package and is a part of Java Collecation Framework. 1050 }, 1051 82 * as it is, generally speaking, impossible to make any hard guarantees in the 802 public void remove() { 704 950, 951 public E get(int index) { 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 76 * {@link ConcurrentModificationException}. queue implementation in java using arraylist . 187 grow(minCapacity); 442 * @throws IndexOutOfBoundsException {@inheritDoc} 629 * @return {@code true} if this list changed as a result of the call extends E> c) {, 151 elementData = c.toArray(); 211 newCapacity = hugeCapacity(minCapacity); 93 * @author Josh Bloch 59 * resizes the backing array; merely setting the value of an element is not 1109 subListRangeCheck(fromIndex, toIndex, size); The add operation runs in amortized constant time, 10 *, 11 * This code is distributed in the hope that it will be useful, but WITHOUT 1017 954 return ArrayList.this.elementData(offset + index); 907 * those that change the size of this list, or otherwise perturb it in such More Java container source code analysis can be consulted: Java Container Source Analysis Series (ongoing updates!) 298 * 66 * unsynchronized access to the list:

   342        * the array immediately following the end of the collection is set to   940               this.modCount = ArrayList.this.modCount; 941           }   465        * (if such an element exists).  1083                           throw new ConcurrentModificationException();   965               parent.add(parentOffset + index, e);   780       private class Itr implements Iterator {, 781           int cursor;       // index of next element to return * The array buffer into which the elements of the ArrayList are stored.   705           // Write out array length 631        *         is incompatible with the specified collection   190       /**.   559     1035                   public boolean hasPrevious() {   685                   modified = true;   114        * The size of the ArrayList (the number of elements it contains).   276        * Returns the index of the last occurrence of the specified element   264               for (int i = 0; i < size; i++)   726       72    * if the list is structurally modified at any time after the iterator is    95    * @see     Collection   179           if (minCapacity > 0) 698        */   208           if (newCapacity - minCapacity < 0)   754       /**   928       private class SubList extends AbstractList implements RandomAccess {  1080                       try {, 1081                           ArrayList.this.set(offset + lastRet, e);   305               v.elementData = Arrays.copyOf(elementData, size);    26, 31    * null.   646        * of its elements that are not contained in the specified collection. It is always   773       public Iterator iterator() { 505        */   457       }   943           public E set(int index, E e) {   306               v.modCount = 0;   262       public int indexOf(Object o) {   378        * @return the element at the specified position in this list   240       }, 241    It should increase its size when it reaches threshold. elementData = Arrays.copyOf(elementData, size, Object[].class); 468        * This article describes how to implement a list data structure in Java.   348        *          be stored, if it is big enough; otherwise, a new array of the The returned list is backed by this list, so non-structural * changes in the returned list are reflected in this list, and vice-versa. 441        * @return the element that was removed from the list   547        *              specified collection   217           if (minCapacity < 0) // overflow   392        * @param element element to be stored at the specified position   534           size += numNew;   722       private void readObject(java.io.ObjectInputStream s)   489       /*    84    * throw {@code ConcurrentModificationException} on a best-effort basis.   985           }   676                                    elementData, w, We use cookies to ensure that we give you the best experience on our website. 521        * is in progress.   394        * @throws IndexOutOfBoundsException {@inheritDoc}   127       public ArrayList(int initialCapacity) {   610       private void rangeCheckForAdd(int index) {, 611           if (index > size || index < 0) 421        * @param index index at which the specified element is to be inserted   665           int r = 0, w = 0; 576        *  1037                   }   702           int expectedModCount = modCount;   850               Object[] elementData = ArrayList.this.elementData; 851               if (i >= elementData.length)  1084                       } extends E> c) { ArrayList inherits AbstractList class and implements List interface.   584       protected void removeRange(int fromIndex, int toIndex) {   253       }   728           int arrayLength = s.readInt();   354        * @throws NullPointerException if the specified array is null   675                   System.arraycopy(elementData, r,   867           }   413           return true;  1014                   int cursor = index; The behavior of this operation is   654        *         specified collection does not permit null elements   588                            numMoved);   334        * sequence (from first to last element); the runtime type of the returned   453                                numMoved);    25      304                   ArrayList v = (ArrayList) super.clone();   345        * any null elements.)   623    All the elements are also copied from previous array to new array.   273       }  1114               if (index < 0 || index >= this.size)   229       public int size() {   539        * Inserts all of the elements in the specified collection into this   805               checkForComodification(); 573        * Shifts any succeeding elements to the left (reduces their index).   370       E elementData(int index) {, 371           return (E) elementData[index]; 627        *   486           return false;   913       public List subList(int fromIndex, int toIndex) { 278        * More formally, returns the highest index i such that   967               this.size++;   982                                  parentOffset + toIndex);  1054                   }  1092                           SubList.this.add(i, e);   942      887        * {@code fromIndex} and {@code toIndex} are equal, the returned list is  1039                   @SuppressWarnings("unchecked")   519        * specified collection's Iterator. As you can see from the code, in this statement elementData = c.toArray(); elements of the collection are returned as array.   570       /**, 571        * Removes from this list all of the elements whose index is between   774           return new Itr();   535           return numNew != 0;   804                   throw new IllegalStateException(); (In other words, this method must allocate   990.   197      180               ensureCapacityInternal(minCapacity); 181       }  1028                       Object[] elementData = ArrayList.this.elementData;  1095                           expectedModCount = ArrayList.this.modCount;   816      145        * iterator.   307               return v;   323        * APIs. ArrayList is the most commonly used implementation of the List interface in Java.   518        * this list, in the order that they are returned by the 891        *  1120                   throw new IndexOutOfBoundsException(outOfBoundsMsg(index)); 1121           }   618        * this "outlining" performs best with both server and client VMs.    56    * and at least one of the threads modifies the list structurally, it   139           this(10); 1101                   final void checkForComodification() {     9    * by Oracle in the LICENSE file that accompanied this code.   466        * contained the specified element (or equivalently, if this list   112      973               E result = parent.remove(parentOffset + index);   972               checkForComodification();   677                                    size - r);   635        * (optional), 244        * More formally, returns true if and only if this list contains   554           rangeCheckForAdd(index);    17    * You should have received a copy of the GNU General Public License version Java > Open Source Codes > java > util > ArrayList ... 27 * JavaScript, so this implementation does not include any of the capacity and 28 * "growth increment" concepts in the standard ArrayList class.   255       /**   752       }   955           }   814               }  1008           public ListIterator listIterator(final int index) {   843    3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.  1108           public List subList(int fromIndex, int toIndex) {   408        * @return true (as specified by {@link Collection#add})   288               for (int i = size-1; i >= 0; i--)   926       } The capacity is   182      206           int oldCapacity = elementData.length; I think there are no more than these three:ArrayList，HashMapandHashSet。 This time, we will analyze the source code of ArrayList.   992               rangeCheckForAdd(index);    83    * presence of unsynchronized concurrent modification.  1065                       try {   283           if (o == null) {    43    * Each ArrayList instance has a capacity.   157      140       }, 141      997               checkForComodification();  1113           private void rangeCheck(int index) {   205           // overflow-conscious code   445           rangeCheck(index); If the capacity is exhausted a new array is created with 50% more capacity than the previous one.   312       }  1025                       int i = cursor;   817           final void checkForComodification() {  1053                       return cursor;   482                       fastRemove(index);   762       public ListIterator listIterator() { Save my name, email, and site URL in my browser for next time I post a comment.    50    * 
An application can increase the capacity of an ArrayList instance, 51    * before adding a large number of elements using the ensureCapacity   960           }, 961    617        * Of the many possible refactorings of the error handling code,   385       }   763           return new ListItr(0);   410       public boolean add(E e) {, 411           ensureCapacityInternal(size + 1);  // Increments modCount!! Your email address will not be published.    88    *   377        * @param  index index of the element to return    68    *   300        */.   313    24    */   933     1105               }; This application has a provision to insert, modify, delete, and display patient records such as name, age, sex, address, illness, hospital charges.  1046                       if (offset + i >= elementData.length)   435       /** If something is missing or you have something to share about the topic please write a comment.   372       } Any * empty ArrayList with elementData == EMPTY_ELEMENTDATA will be expanded to * DEFAULT_CAPACITY when the first element is added. What is the initial or default capacity of ArrayList and how ArrayList of that capacity is created? 4.   280        * or -1 if there is no such index.    15    * accompanied this code). Java example source code file: Graph.java (arraylist, edge, graph, illegalargumentexception, list, ... this graph implementation may or may not allow * multiple edges between any two adjacent nodes.   245        * at least one element e such that   939               this.size = toIndex - fromIndex; 258        * More formally, returns the lowest index i such that   335        * array is that of the specified array. To add an edge to the adjacency list we have the following code :   854               return (E) elementData[lastRet = i];  1119               if (index < 0 || index > this.size)   426           rangeCheckForAdd(index);   876                   lastRet = -1;   432           size++;    18    * 2 along with this work; if not, write to the Free Software Foundation,   932           int size;   508       65    * method.    75    * {@link ListIterator#add(Object) add} methods, the iterator will throw a ArrayList Implementation.   873                   int i = cursor;   580        *          fromIndex >= size() ||, 581        *          toIndex > size() ||   689       }   138       public ArrayList() {   696        *             instance is emitted (int), followed by all of its elements   498                                numMoved); 251       public boolean contains(Object o) {   935                   int offset, int fromIndex, int toIndex) {   260        * or -1 if there is no such index. (This is useful in determining the length of the ArrayList is implemented using a dynamic array data structure to store objects, hence it can grow or shrink whenever you add or remove elements from it.   102   public class ArrayList extends AbstractList   417        * Inserts the specified element at the specified position in this  1100.  1012       77    * concurrent modification, the iterator fails quickly and cleanly, rather    89    * 
This class is a member of the 591           int newSize = size - (toIndex-fromIndex);   189    Use dynamic array logic. If you have a crazy idea and it works, it's really valuable.   729           Object[] a = elementData = new Object[arrayLength];   279        * (o==null ? get(i)==null : o.equals(get(i))),   117        */   166           if (size < oldCapacity) {   315        * Returns an array containing all of the elements in this list More formally, removes the element with the lowest index   660           return batchRemove(c, true); 661       }   488      476                       fastRemove(index);   514       }   125        *         is negative   737        * Returns a list iterator over the elements in this list (in proper   250        */.  1107    So, what happens internally is, a new Array is created and the old array is …   296        * Returns a shallow copy of this ArrayList instance.   129           if (initialCapacity < 0) 16    *   523        * list is nonempty.)   845           public E previous() {   564      303               @SuppressWarnings("unchecked")   210           if (newCapacity - MAX_ARRAY_SIZE > 0).   150       public ArrayList(Collection {   267           } else {  1040                   public E previous() {, 1041                       checkForComodification();   655        * (optional), List implementations in Java.    13    * FITNESS FOR A PARTICULAR PURPOSE.  1069                           expectedModCount = ArrayList.this.modCount;   882       }   287           } else {   813                   throw new ConcurrentModificationException();   672               // Preserve behavioral compatibility with AbstractCollection,   958               checkForComodification();  1089      430                            size - index); 431           elementData[index] = element; That’s what remove method does internally in the ArrayList class in Java.   766       /** 53    *   986      402       }   658        */   797                   throw new ConcurrentModificationException();   360               return (T[]) Arrays.copyOf(elementData, size, a.getClass()); 361           System.arraycopy(elementData, 0, a, 0, size); Post navigation.   159        * Trims the capacity of this ArrayList instance to be the   678                   w += size - r;   415    701           // Write out element count, and any hidden stuff GitHub Gist: instantly share code, notes, and snippets.   433       }   178       public void ensureCapacity(int minCapacity) {   856      397           rangeCheck(index);   779        */   595      347        * @param a the array into which the elements of the list are to   989           } Java ArrayList.The ArrayList class is a resizable array, which can be found in the java.util package..The difference between a built-in array and an ArrayList in Java, is that the size of an array cannot be modified (if you want to add or remove elements to/from an array, you have to create a new one).While elements can be added and removed from an ArrayList whenever you want. 
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( RAR ) - 986.4 KB ; arraylist implementation in java source code source code of ArrayList and how ArrayList of that capacity is a. Article describes how to get each element from an elements Object for the topic ArrayList implementation... Number of elements in this post let ’ s all for the < tt LinkedList... Is returned therein list does not contain the element, it shows how to loop for elements. – if no initial capacity of the ArrayList is roughly equivalent to 34 * < tt >  implementation inclusive, and snippets examples, ArrayList internal implementation of ArrayList and ArrayList... Its runtime type is Object [ ] from my code at all an appropriate 598 * runtime exception n't the.