|
1
53
54 package com.Yasna.forum.database;
55
56 import java.util.*;
57 import java.sql.*;
59 import com.Yasna.forum.*;
60
61
64 public class DbGroupIterator implements Iterator, ListIterator {
65
66
67 private static final String  ALL_GROUPS = "SELECT groupID from yazdGroup";
68
69 private int currentIndex = -1;
70 private int [] groups;
71
72 private ProfileManager profileManager;
73
74 protected DbGroupIterator(ProfileManager profileManager) {
75 this.profileManager = profileManager;
76 ArrayList tempGroups = new ArrayList();
79 Connection con = null;
80 PreparedStatement pstmt = null;
81 try {
82 con = DbConnectionManager.getConnection();
83 pstmt = con.prepareStatement(ALL_GROUPS);
84 ResultSet rs = pstmt.executeQuery();
85 while (rs.next()) {
86 tempGroups.add(new Integer (rs.getInt("groupID")));
87 }
88 }
89 catch( SQLException sqle ) {
90 System.err.println("Error in DbGroupIterator:constructor()-" + sqle);
91 }
92 finally {
93 try { pstmt.close(); }
94 catch (Exception e) { e.printStackTrace(); }
95 try { con.close(); }
96 catch (Exception e) { e.printStackTrace(); }
97 }
98 groups = new int[tempGroups.size()];
99 for (int i=0; i<groups.length; i++) {
100 groups[i] = ((Integer )tempGroups.get(i)).intValue();
101 }
102 }
103
104 protected DbGroupIterator(ProfileManager profileManager, int startIndex,
105 int numResults)
106 {
107 this.profileManager = profileManager;
108
109 int[] tempResults = new int[numResults];
110 int resultCount = 0;
114
115 Connection con = null;
116 PreparedStatement pstmt = null;
117
118 try {
119 con = DbConnectionManager.getConnection();
120 pstmt = con.prepareStatement(ALL_GROUPS);
121 ResultSet rs = pstmt.executeQuery();
122 for (int i=0; i<startIndex; i++) {
124 rs.next();
125 }
126 for (int i=0; i<numResults; i++) {
128 if (rs.next()) {
129 tempResults[resultCount] = rs.getInt("groupID");
130 resultCount++;
131 }
132 else {
133 break;
134 }
135 }
136 }
137 catch( SQLException sqle ) {
138 System.err.println("Error in DbGroupIterator:constructor()-" + sqle);
139 }
140 finally {
141 try { pstmt.close(); }
142 catch (Exception e) { e.printStackTrace(); }
143 try { con.close(); }
144 catch (Exception e) { e.printStackTrace(); }
145 }
146 groups = new int[resultCount];
147 for (int i=0; i<resultCount; i++) {
148 groups[i] = tempResults[i];
149 }
150 }
151
152
155 public boolean hasNext() {
156 return (currentIndex+1 < groups.length);
157 }
158
159
162 public Object next() throws java.util.NoSuchElementException {
163 Group group = null;
164 currentIndex++;
165 if (currentIndex >= groups.length) {
166 throw new java.util.NoSuchElementException ();
167 }
168 try {
169 group = profileManager.getGroup(groups[currentIndex]);
170 }
171 catch (GroupNotFoundException gnfe) {
172 System.err.println(gnfe);
173 }
174 return group;
175 }
176
177
183 public void remove() {
184 throw new UnsupportedOperationException ();
185 }
186
187
190 public boolean hasPrevious() {
191 return (currentIndex > 0);
192 }
193
194
200 public void add(Object o) throws UnsupportedOperationException {
201 throw new UnsupportedOperationException ();
202 }
203
204
210 public void set(Object o) throws UnsupportedOperationException {
211 throw new UnsupportedOperationException ();
212 }
213
214
217 public int nextIndex() {
218 return currentIndex+1;
219 }
220
221
224 public Object previous() throws java.util.NoSuchElementException {
225 Group group = null;
226 currentIndex--;
227 if (currentIndex < 0) {
228 currentIndex++;
229 throw new java.util.NoSuchElementException ();
230 }
231 try {
232 group = profileManager.getGroup(groups[currentIndex]);
233 }
234 catch (GroupNotFoundException gnfe) {
235 System.err.println(gnfe);
236 }
237 return group;
238 }
239
240
243 public int previousIndex() {
244 return currentIndex-1;
245 }
246 }
247
248 |
Popular Tags |
Java API By Example, From Geeks To Geeks.