traininfo/util/AndroidTimeoutCache.java

package dk.thoerup.traininfo.util;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Set;


public class AndroidTimeoutCache<K,V> {

        class CacheItem<T> {
                
                public CacheItem(T v) {
                        value = v;
                        lastupdate = android.os.SystemClock.elapsedRealtime();
                }
                
                public boolean isExpired(long now) {
                        return ( (lastupdate+timeout) < now);
                }
                
                public long lastupdate;
                public T value;
        }
        
        private HashMap<K,CacheItem<V>> cache = new HashMap<K,CacheItem<V>>();
        private long timeout;
        
        public AndroidTimeoutCache(int timeout) {
                this.timeout = timeout; 
        }
        
        public void purgeOldEntries() {
                
                long now = android.os.SystemClock.elapsedRealtime();
                //Log.e("Purge","Purge");
                
                Set<K> keyset = cache.keySet();
                
                for ( Iterator<K> it = keyset.iterator(); it.hasNext() ;) {
                        K key = it.next();
                        
                        CacheItem<V> item = cache.get(key);
                        if ( item.isExpired(now)) { //item too old
                                it.remove();
                                //Log.e("Purge", "removing");
                        }                       
                }       
                
        }
        
        public void put(K k, V v) {
                CacheItem<V> item= new CacheItem<V>(v);
                cache.put(k, item);
        }
        
        public V get(K k) {
                long now = android.os.SystemClock.elapsedRealtime();
                
                CacheItem<V> item = cache.get(k);
                                
                
                if (item != null) {
                        if ( item.isExpired(now) ) { //item too old
                                return null;
                        } else {
                                return item.value; //item still good
                        }
                } else {
                        return null; // no item found
                }
                
        }
        
}
1	package dk.thoerup.traininfo.util;
2
3	import java.util.HashMap;
4	import java.util.Iterator;
5	import java.util.Set;
6
7
8
9	public class AndroidTimeoutCache<K,V> {
10
11	class CacheItem<T> {
12
13	public CacheItem(T v) {
14	value = v;
15	lastupdate = android.os.SystemClock.elapsedRealtime();
16	}
17
18	public boolean isExpired(long now) {
19	return ( (lastupdate+timeout) < now);
20	}
21
22	public long lastupdate;
23	public T value;
24	}
25
26	private HashMap<K,CacheItem<V>> cache = new HashMap<K,CacheItem<V>>();
27	private long timeout;
28
29	public AndroidTimeoutCache(int timeout) {
30	this.timeout = timeout;
31	}
32
33	public void purgeOldEntries() {
34
35	long now = android.os.SystemClock.elapsedRealtime();
36	//Log.e("Purge","Purge");
37
38	Set<K> keyset = cache.keySet();
39
40	for ( Iterator<K> it = keyset.iterator(); it.hasNext() ;) {
41	K key = it.next();
42
43	CacheItem<V> item = cache.get(key);
44	if ( item.isExpired(now)) { //item too old
45	it.remove();
46	//Log.e("Purge", "removing");
47	}
48	}
49
50	}
51
52	public void put(K k, V v) {
53	CacheItem<V> item= new CacheItem<V>(v);
54	cache.put(k, item);
55	}
56
57	public V get(K k) {
58	long now = android.os.SystemClock.elapsedRealtime();
59
60	CacheItem<V> item = cache.get(k);
61
62
63	if (item != null) {
64	if ( item.isExpired(now) ) { //item too old
65	return null;
66	} else {
67	return item.value; //item still good
68	}
69	} else {
70	return null; // no item found
71	}
72
73	}
74
75	}