| /* ==================================================================== |
| Licensed to the Apache Software Foundation (ASF) under one or more |
| contributor license agreements. See the NOTICE file distributed with |
| this work for additional information regarding copyright ownership. |
| The ASF licenses this file to You under the Apache License, Version 2.0 |
| (the "License"); you may not use this file except in compliance with |
| the License. You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| ==================================================================== */ |
| |
| package org.apache.poi.util; |
| |
| /** |
| * A List of short's; as full an implementation of the java.util.List |
| * interface as possible, with an eye toward minimal creation of |
| * objects |
| * |
| * the mimicry of List is as follows: |
| * <ul> |
| * <li> if possible, operations designated 'optional' in the List |
| * interface are attempted |
| * <li> wherever the List interface refers to an Object, substitute |
| * short |
| * <li> wherever the List interface refers to a Collection or List, |
| * substitute ShortList |
| * </ul> |
| * |
| * the mimicry is not perfect, however: |
| * <ul> |
| * <li> operations involving Iterators or ListIterators are not |
| * supported |
| * <li> remove(Object) becomes removeValue to distinguish it from |
| * remove(short index) |
| * <li> subList is not supported |
| * </ul> |
| * |
| * @author Marc Johnson |
| */ |
| |
| public class ShortList |
| { |
| private short[] _array; |
| private int _limit; |
| private static final int _default_size = 128; |
| |
| /** |
| * create an ShortList of default size |
| */ |
| |
| public ShortList() |
| { |
| this(_default_size); |
| } |
| |
| /** |
| * create a copy of an existing ShortList |
| * |
| * @param list the existing ShortList |
| */ |
| |
| public ShortList(final ShortList list) |
| { |
| this(list._array.length); |
| System.arraycopy(list._array, 0, _array, 0, _array.length); |
| _limit = list._limit; |
| } |
| |
| /** |
| * create an ShortList with a predefined initial size |
| * |
| * @param initialCapacity the size for the internal array |
| */ |
| |
| public ShortList(final int initialCapacity) |
| { |
| _array = new short[ initialCapacity ]; |
| _limit = 0; |
| } |
| |
| /** |
| * add the specfied value at the specified index |
| * |
| * @param index the index where the new value is to be added |
| * @param value the new value |
| * |
| * @exception IndexOutOfBoundsException if the index is out of |
| * range (index < 0 || index > size()). |
| */ |
| |
| public void add(final int index, final short value) |
| { |
| if (index > _limit) |
| { |
| throw new IndexOutOfBoundsException(); |
| } |
| else if (index == _limit) |
| { |
| add(value); |
| } |
| else |
| { |
| |
| // index < limit -- insert into the middle |
| if (_limit == _array.length) |
| { |
| growArray(_limit * 2); |
| } |
| System.arraycopy(_array, index, _array, index + 1, |
| _limit - index); |
| _array[ index ] = value; |
| _limit++; |
| } |
| } |
| |
| /** |
| * Appends the specified element to the end of this list |
| * |
| * @param value element to be appended to this list. |
| * |
| * @return true (as per the general contract of the Collection.add |
| * method). |
| */ |
| |
| public boolean add(final short value) |
| { |
| if (_limit == _array.length) |
| { |
| growArray(_limit * 2); |
| } |
| _array[ _limit++ ] = value; |
| return true; |
| } |
| |
| /** |
| * Appends all of the elements in the specified collection to the |
| * end of this list, in the order that they are returned by the |
| * specified collection's iterator. The behavior of this |
| * operation is unspecified if the specified collection is |
| * modified while the operation is in progress. (Note that this |
| * will occur if the specified collection is this list, and it's |
| * nonempty.) |
| * |
| * @param c collection whose elements are to be added to this |
| * list. |
| * |
| * @return true if this list changed as a result of the call. |
| */ |
| |
| public boolean addAll(final ShortList c) |
| { |
| if (c._limit != 0) |
| { |
| if ((_limit + c._limit) > _array.length) |
| { |
| growArray(_limit + c._limit); |
| } |
| System.arraycopy(c._array, 0, _array, _limit, c._limit); |
| _limit += c._limit; |
| } |
| return true; |
| } |
| |
| /** |
| * Inserts all of the elements in the specified collection into |
| * this list at the specified position. Shifts the element |
| * currently at that position (if any) and any subsequent elements |
| * to the right (increases their indices). The new elements will |
| * appear in this list in the order that they are returned by the |
| * specified collection's iterator. The behavior of this |
| * operation is unspecified if the specified collection is |
| * modified while the operation is in progress. (Note that this |
| * will occur if the specified collection is this list, and it's |
| * nonempty.) |
| * |
| * @param index index at which to insert first element from the |
| * specified collection. |
| * @param c elements to be inserted into this list. |
| * |
| * @return true if this list changed as a result of the call. |
| * |
| * @exception IndexOutOfBoundsException if the index is out of |
| * range (index < 0 || index > size()) |
| */ |
| |
| public boolean addAll(final int index, final ShortList c) |
| { |
| if (index > _limit) |
| { |
| throw new IndexOutOfBoundsException(); |
| } |
| if (c._limit != 0) |
| { |
| if ((_limit + c._limit) > _array.length) |
| { |
| growArray(_limit + c._limit); |
| } |
| |
| // make a hole |
| System.arraycopy(_array, index, _array, index + c._limit, |
| _limit - index); |
| |
| // fill it in |
| System.arraycopy(c._array, 0, _array, index, c._limit); |
| _limit += c._limit; |
| } |
| return true; |
| } |
| |
| /** |
| * Removes all of the elements from this list. This list will be |
| * empty after this call returns (unless it throws an exception). |
| */ |
| |
| public void clear() |
| { |
| _limit = 0; |
| } |
| |
| /** |
| * Returns true if this list contains the specified element. More |
| * formally, returns true if and only if this list contains at |
| * least one element e such that o == e |
| * |
| * @param o element whose presence in this list is to be tested. |
| * |
| * @return true if this list contains the specified element. |
| */ |
| |
| public boolean contains(final short o) |
| { |
| boolean rval = false; |
| |
| for (int j = 0; !rval && (j < _limit); j++) |
| { |
| if (_array[ j ] == o) |
| { |
| rval = true; |
| } |
| } |
| return rval; |
| } |
| |
| /** |
| * Returns true if this list contains all of the elements of the |
| * specified collection. |
| * |
| * @param c collection to be checked for containment in this list. |
| * |
| * @return true if this list contains all of the elements of the |
| * specified collection. |
| */ |
| |
| public boolean containsAll(final ShortList c) |
| { |
| boolean rval = true; |
| |
| if (this != c) |
| { |
| for (int j = 0; rval && (j < c._limit); j++) |
| { |
| if (!contains(c._array[ j ])) |
| { |
| rval = false; |
| } |
| } |
| } |
| return rval; |
| } |
| |
| /** |
| * Compares the specified object with this list for equality. |
| * Returns true if and only if the specified object is also a |
| * list, both lists have the same size, and all corresponding |
| * pairs of elements in the two lists are equal. (Two elements e1 |
| * and e2 are equal if e1 == e2.) In other words, two lists are |
| * defined to be equal if they contain the same elements in the |
| * same order. This definition ensures that the equals method |
| * works properly across different implementations of the List |
| * interface. |
| * |
| * @param o the object to be compared for equality with this list. |
| * |
| * @return true if the specified object is equal to this list. |
| */ |
| |
| public boolean equals(final Object o) |
| { |
| boolean rval = this == o; |
| |
| if (!rval && (o != null) && (o.getClass() == this.getClass())) |
| { |
| ShortList other = ( ShortList ) o; |
| |
| if (other._limit == _limit) |
| { |
| |
| // assume match |
| rval = true; |
| for (int j = 0; rval && (j < _limit); j++) |
| { |
| rval = _array[ j ] == other._array[ j ]; |
| } |
| } |
| } |
| return rval; |
| } |
| |
| /** |
| * Returns the element at the specified position in this list. |
| * |
| * @param index index of element to return. |
| * |
| * @return the element at the specified position in this list. |
| * |
| * @exception IndexOutOfBoundsException if the index is out of |
| * range (index < 0 || index >= size()). |
| */ |
| |
| public short get(final int index) |
| { |
| if (index >= _limit) |
| { |
| throw new IndexOutOfBoundsException(); |
| } |
| return _array[ index ]; |
| } |
| |
| /** |
| * Returns the hash code value for this list. The hash code of a |
| * list is defined to be the result of the following calculation: |
| * |
| * <code> |
| * hashCode = 1; |
| * Iterator i = list.iterator(); |
| * while (i.hasNext()) { |
| * Object obj = i.next(); |
| * hashCode = 31*hashCode + (obj==null ? 0 : obj.hashCode()); |
| * } |
| * </code> |
| * |
| * This ensures that list1.equals(list2) implies that |
| * list1.hashCode()==list2.hashCode() for any two lists, list1 and |
| * list2, as required by the general contract of Object.hashCode. |
| * |
| * @return the hash code value for this list. |
| */ |
| |
| public int hashCode() |
| { |
| int hash = 0; |
| |
| for (int j = 0; j < _limit; j++) |
| { |
| hash = (31 * hash) + _array[ j ]; |
| } |
| return hash; |
| } |
| |
| /** |
| * Returns the index in this list of the first occurrence of the |
| * specified element, or -1 if this list does not contain this |
| * element. More formally, returns the lowest index i such that |
| * (o == get(i)), or -1 if there is no such index. |
| * |
| * @param o element to search for. |
| * |
| * @return the index in this list of the first occurrence of the |
| * specified element, or -1 if this list does not contain |
| * this element. |
| */ |
| |
| public int indexOf(final short o) |
| { |
| int rval = 0; |
| |
| for (; rval < _limit; rval++) |
| { |
| if (o == _array[ rval ]) |
| { |
| break; |
| } |
| } |
| if (rval == _limit) |
| { |
| rval = -1; // didn't find it |
| } |
| return rval; |
| } |
| |
| /** |
| * Returns true if this list contains no elements. |
| * |
| * @return true if this list contains no elements. |
| */ |
| |
| public boolean isEmpty() |
| { |
| return _limit == 0; |
| } |
| |
| /** |
| * Returns the index in this list of the last occurrence of the |
| * specified element, or -1 if this list does not contain this |
| * element. More formally, returns the highest index i such that |
| * (o == get(i)), or -1 if there is no such index. |
| * |
| * @param o element to search for. |
| * |
| * @return the index in this list of the last occurrence of the |
| * specified element, or -1 if this list does not contain |
| * this element. |
| */ |
| |
| public int lastIndexOf(final short o) |
| { |
| int rval = _limit - 1; |
| |
| for (; rval >= 0; rval--) |
| { |
| if (o == _array[ rval ]) |
| { |
| break; |
| } |
| } |
| return rval; |
| } |
| |
| /** |
| * Removes the element at the specified position in this list. |
| * Shifts any subsequent elements to the left (subtracts one from |
| * their indices). Returns the element that was removed from the |
| * list. |
| * |
| * @param index the index of the element to removed. |
| * |
| * @return the element previously at the specified position. |
| * |
| * @exception IndexOutOfBoundsException if the index is out of |
| * range (index < 0 || index >= size()). |
| */ |
| |
| public short remove(final int index) |
| { |
| if (index >= _limit) |
| { |
| throw new IndexOutOfBoundsException(); |
| } |
| short rval = _array[ index ]; |
| |
| System.arraycopy(_array, index + 1, _array, index, _limit - index); |
| _limit--; |
| return rval; |
| } |
| |
| /** |
| * Removes the first occurrence in this list of the specified |
| * element (optional operation). If this list does not contain |
| * the element, it is unchanged. More formally, removes the |
| * element with the lowest index i such that (o.equals(get(i))) |
| * (if such an element exists). |
| * |
| * @param o element to be removed from this list, if present. |
| * |
| * @return true if this list contained the specified element. |
| */ |
| |
| public boolean removeValue(final short o) |
| { |
| boolean rval = false; |
| |
| for (int j = 0; !rval && (j < _limit); j++) |
| { |
| if (o == _array[ j ]) |
| { |
| System.arraycopy(_array, j + 1, _array, j, _limit - j); |
| _limit--; |
| rval = true; |
| } |
| } |
| return rval; |
| } |
| |
| /** |
| * Removes from this list all the elements that are contained in |
| * the specified collection |
| * |
| * @param c collection that defines which elements will be removed |
| * from this list. |
| * |
| * @return true if this list changed as a result of the call. |
| */ |
| |
| public boolean removeAll(final ShortList c) |
| { |
| boolean rval = false; |
| |
| for (int j = 0; j < c._limit; j++) |
| { |
| if (removeValue(c._array[ j ])) |
| { |
| rval = true; |
| } |
| } |
| return rval; |
| } |
| |
| /** |
| * Retains only the elements in this list that are contained in |
| * the specified collection. In other words, removes from this |
| * list all the elements that are not contained in the specified |
| * collection. |
| * |
| * @param c collection that defines which elements this set will |
| * retain. |
| * |
| * @return true if this list changed as a result of the call. |
| */ |
| |
| public boolean retainAll(final ShortList c) |
| { |
| boolean rval = false; |
| |
| for (int j = 0; j < _limit; ) |
| { |
| if (!c.contains(_array[ j ])) |
| { |
| remove(j); |
| rval = true; |
| } |
| else |
| { |
| j++; |
| } |
| } |
| return rval; |
| } |
| |
| /** |
| * Replaces the element at the specified position in this list |
| * with the specified element |
| * |
| * @param index index of element to replace. |
| * @param element element to be stored at the specified position. |
| * |
| * @return the element previously at the specified position. |
| * |
| * @exception IndexOutOfBoundsException if the index is out of |
| * range (index < 0 || index >= size()). |
| */ |
| |
| public short set(final int index, final short element) |
| { |
| if (index >= _limit) |
| { |
| throw new IndexOutOfBoundsException(); |
| } |
| short rval = _array[ index ]; |
| |
| _array[ index ] = element; |
| return rval; |
| } |
| |
| /** |
| * Returns the number of elements in this list. If this list |
| * contains more than Integer.MAX_VALUE elements, returns |
| * Integer.MAX_VALUE. |
| * |
| * @return the number of elements in this ShortList |
| */ |
| |
| public int size() |
| { |
| return _limit; |
| } |
| |
| /** |
| * Returns an array containing all of the elements in this list in |
| * proper sequence. Obeys the general contract of the |
| * Collection.toArray method. |
| * |
| * @return an array containing all of the elements in this list in |
| * proper sequence. |
| */ |
| |
| public short [] toArray() |
| { |
| short[] rval = new short[ _limit ]; |
| |
| System.arraycopy(_array, 0, rval, 0, _limit); |
| return rval; |
| } |
| |
| /** |
| * Returns an array containing all of the elements in this list in |
| * proper sequence. Obeys the general contract of the |
| * Collection.toArray(Object[]) method. |
| * |
| * @param a the array into which the elements of this list are to |
| * be stored, if it is big enough; otherwise, a new array |
| * is allocated for this purpose. |
| * |
| * @return an array containing the elements of this list. |
| */ |
| |
| public short [] toArray(final short [] a) |
| { |
| short[] rval; |
| |
| if (a.length == _limit) |
| { |
| System.arraycopy(_array, 0, a, 0, _limit); |
| rval = a; |
| } |
| else |
| { |
| rval = toArray(); |
| } |
| return rval; |
| } |
| |
| private void growArray(final int new_size) |
| { |
| int size = (new_size == _array.length) ? new_size + 1 |
| : new_size; |
| short[] new_array = new short[ size ]; |
| |
| System.arraycopy(_array, 0, new_array, 0, _limit); |
| _array = new_array; |
| } |
| } // end public class ShortList |
| |