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24 package org.objectweb.jalisto.se.impl.cache;
25
26 import org.objectweb.jalisto.se.api.cache.JalistoCache;
27 import org.objectweb.jalisto.se.impl.trace.Trace;
28
29 import java.io.PrintStream  ;
30 import java.util.*;
31
32 public class GenericCache implements JalistoCache {
33
34 public GenericCache() {
35 table = new HashMap();
36 }
37
38 public void init(int size, String name, double clearPourcent) {
39 this.maxSize = size;
40 this.name = name;
41 this.cacheClearPourcent = clearPourcent;
42 }
43
44 public void setTrace(Trace trace) {
45 this.trace = trace;
46 }
47
48 public boolean isEmpty() {
49 return table.isEmpty();
50 }
51
52 public void clear() {
53 trace.println(Trace.CACHE, "{0} : clear()", name);
54 table.clear();
55 firstCell = null;
56 lastCell = null;
57 }
58
59 public boolean containsKey(Object key) {
60 return table.containsKey(key);
61 }
62
63 public boolean containsValue(Object value) {
64 throw new UnsupportedOperationException ("not used in this implementation");
65 }
66
67 public Set entrySet() {
68 throw new UnsupportedOperationException ("not used in this implementation");
69 }
70
71 public Object get(Object key) {
72 trace.println(Trace.CACHE, "{0} : get({1})", name, key);
73 Object result = table.get(key);
74 if (result != null) {
75 return ((CacheCell) result).getObject();
76 }
77 return null;
78 }
79
80 public Set keySet() {
81 return table.keySet();
82 }
83
84 public Object put(Object key, Object value) {
85 trace.println(Trace.CACHE, "{0} : put({1}, {2})", name, key, value);
86 if (containsKey(key)) {
87 ((CacheCell) table.get(key)).setObject(value);
88 } else {
89 trace.println(Trace.CACHE, "{0} : put -> add");
90 if (table.size() >= maxSize) {
91 makeSpace();
92 }
93 CacheCell availableCacheCell = CacheCell.newInstance(key, value);
94 if (lastCell != null) {
95 lastCell.setNextCell(availableCacheCell);
96 availableCacheCell.setPrecedingCell(lastCell);
97 lastCell = availableCacheCell;
98 } else {
99 lastCell = availableCacheCell;
100 firstCell = availableCacheCell;
101 }
102 table.put(key, availableCacheCell);
103 }
104 return null;
105 }
106
107 public void putAll(Map map) {
108 Iterator keys = map.keySet().iterator();
109 while (keys.hasNext()) {
110 Object key = keys.next();
111 put(key, map.get(key));
112 }
113 }
114
115 public Object remove(Object key) {
116 trace.println(Trace.CACHE, "{0} : remove({1})", name, key);
117 if (containsKey(key)) {
118 synchronized (table) {
119 CacheCell cell = (CacheCell) table.remove(key);
120 if (cell.equals(firstCell)) {
121 firstCell = cell.getNextCell();
122 }
123 if (cell.equals(lastCell)) {
124 lastCell = cell.getPrecedingCell();
125 }
126 Object result = cell.getObject();
127 cell.delink();
128 if (table.isEmpty()) {
129 lastCell = null;
130 firstCell = null;
131 }
132 return result;
133 }
134 }
135 return null;
136 }
137
138 public int size() {
139 return table.size();
140 }
141
142 public synchronized void setMaxSize(int size) {
143 maxSize = size;
144 CacheCell myFirst = firstCell;
145 synchronized (table) {
146 while (table.size() > maxSize) {
147 CacheCell mySecond = myFirst.getNextCell();
148 table.remove(myFirst.getId());
149 myFirst.delink();
150 myFirst = mySecond;
151 }
152 if (table.isEmpty()) {
153 lastCell = null;
154 firstCell = null;
155 }
156 firstCell = myFirst;
157 }
158 }
159
160 public int getMaxSize() {
161 return maxSize;
162 }
163
164 public Collection values() {
165 throw new UnsupportedOperationException ("not used in this implementation");
166 }
167
168
169 private void makeSpace() {
170 int nbrToRemove = (new Double (maxSize * cacheClearPourcent)).intValue();
171 trace.println(Trace.CACHE, "{0} : makeSpace() : clear {1} objects", name, new Integer (nbrToRemove));
172
173 CacheCell myFirst = firstCell;
174 synchronized (table) {
175 for (int i = 0; i < nbrToRemove; i++) {
176 CacheCell mySecond = myFirst.getNextCell();
177 if (mySecond == null) {
178 throw new NullPointerException ();
179 }
180 table.remove(myFirst.getId());
181 myFirst.delink();
182 myFirst = mySecond;
183 }
184 }
185 firstCell = myFirst;
186 }
187
188 public void print(PrintStream out) {
189 out.println(table.toString());
190 }
191
192 public String toString() {
193 return table.toString();
194 }
195
196
197 private CacheCell firstCell;
198 private CacheCell lastCell;
199 private HashMap table;
200 private String name;
201 private double cacheClearPourcent;
202 private int maxSize;
203 private Trace trace;
204 }
205 |
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