001 package data.filters;
002
003 import data.*;
004 import data.events.*;
005
006 import java.util.*;
007
008 /**
009 * StockFilter for StoringStocks.
010 *
011 * <p>The filter condition can be defined by overriding method
012 * {@link #contains(data.StockItem, data.DataBasket)}.</p>
013 *
014 * @author Steffen Zschaler
015 * @version 2.0 19/08/1999
016 * @since v2.0
017 */
018 public abstract class StoringStockFilter<T extends StockItem, CT extends CatalogItem>
019 extends AbstractStockFilter<T, CT> implements StoringStock<T, CT> {
020
021 /**
022 * Create a new StoringStockFilter.
023 *
024 * @param ssSource the source Stock.
025 */
026 public StoringStockFilter(StoringStock<T, CT> ssSource) {
027 super(ssSource);
028 }
029
030 /**
031 * Get all StockItems for a given key that are contained in the filtered Stock.
032 *
033 * @override Never
034 */
035 public Iterator<T> get(final String sKey, final DataBasket db, final boolean fForEdit) {
036 class I implements Iterator<T> {
037 protected Iterator<T> m_iIterator = m_stSource.get(sKey, db, fForEdit);
038 protected T m_siCurrent;
039 protected T m_siNext;
040
041 public boolean hasNext() {
042 return findNext(false);
043 }
044
045 public T next() {
046 if (!findNext(true)) {
047 throw new NoSuchElementException();
048 }
049
050 return m_siCurrent;
051 }
052
053 public void remove() {
054 if (m_siCurrent == null) {
055 throw new IllegalStateException();
056 }
057
058 try {
059 StoringStockFilter.this.remove(m_siCurrent, db);
060 }
061 catch (VetoException ve) {
062 throw new UnsupportedOperationException();
063 }
064 }
065
066 private boolean findNext(boolean fGet) {
067 if (m_siNext != null) {
068 if (fGet) {
069 m_siCurrent = m_siNext;
070 m_siNext = null;
071 }
072
073 return true;
074 }
075
076 while (m_iIterator.hasNext()) {
077 T si = m_iIterator.next();
078
079 if (contains(si, db)) {
080 if (fGet) {
081 m_siCurrent = si;
082 m_siNext = null;
083 } else {
084 m_siNext = si;
085 }
086
087 return true;
088 }
089 }
090
091 return false;
092 }
093 }
094
095 return new I();
096 }
097
098 /**
099 * Count all StockItems for a given key that are contained in the filtered Stock.
100 *
101 * @override Never
102 */
103 public int countItems(String sKey, DataBasket db) {
104 int nCount = 0;
105
106 for (Iterator<T> i = get(sKey, db, false); i.hasNext(); ) {
107 nCount++;
108 i.next();
109 }
110
111 return nCount;
112 }
113
114 /**
115 * Filter condition: Check whether a given item is contained in the filtered Stock.
116 *
117 * @override Always
118 *
119 * @param si the StockItem to be checked.
120 * @param db the DataBasket to be used to check visibility.
121 *
122 * @return true if the given item is to be contained in the filtered Stock.
123 */
124 public abstract boolean contains(StockItem si, DataBasket db);
125
126 /**
127 * Check whether the given Stock is contained in the filtered Stock.
128 *
129 * @override Never
130 */
131 public boolean containsStock(Stock<T, CT> st, DataBasket db) {
132 boolean fResult = m_stSource.containsStock(st, db);
133
134 if (fResult) {
135 for (Iterator<T> i = st.iterator(db, false); i.hasNext(); ) {
136 if (!contains(i.next(), db)) {
137 return false;
138 }
139 }
140 }
141
142 return fResult;
143 }
144 }