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1 package org.hibernate.cache;
3
4 import java.io.Serializable  ;
5 import java.util.ArrayList ;
6 import java.util.List ;
7 import java.util.Properties ;
8 import java.util.Set ;
9
10 import org.apache.commons.logging.Log;
11 import org.apache.commons.logging.LogFactory;
12
13 import org.hibernate.HibernateException;
14 import org.hibernate.cfg.Settings;
15 import org.hibernate.engine.SessionImplementor;
16 import org.hibernate.type.Type;
17 import org.hibernate.type.TypeFactory;
18
19
27 public class StandardQueryCache implements QueryCache {
28
29 private static final Log log = LogFactory.getLog(StandardQueryCache.class);
30
31 private Cache queryCache;
32 private UpdateTimestampsCache updateTimestampsCache;
33 private final String regionName;
34
35 public void clear() throws CacheException {
36 queryCache.clear();
37 }
38
39 public StandardQueryCache(
40 final Settings settings,
41 final Properties props,
42 final UpdateTimestampsCache updateTimestampsCache,
43 String regionName)
44 throws HibernateException {
45
46 if (regionName==null) regionName = StandardQueryCache.class.getName();
47 String prefix = settings.getCacheRegionPrefix();
48 if (prefix!=null) regionName = prefix + '.' + regionName;
49
50 log.info("starting query cache at region: " + regionName);
51
52 this.queryCache = settings.getCacheProvider().buildCache(regionName, props);
53 this.updateTimestampsCache = updateTimestampsCache;
54 this.regionName = regionName;
55 }
56
57 public void put(QueryKey key, Type[] returnTypes, List result, SessionImplementor session)
58 throws HibernateException {
59 if ( log.isDebugEnabled() ) log.debug("caching query results in region: " + regionName);
60 List cacheable = new ArrayList ( result.size()+1 );
61 cacheable.add( new Long ( session.getTimestamp() ) );
62 for ( int i=0; i<result.size(); i++ ) {
63 if ( returnTypes.length==1 ) {
64 cacheable.add( returnTypes[0].disassemble( result.get(i), session, null ) );
65 }
66 else {
67 cacheable.add( TypeFactory.disassemble( (Object []) result.get(i), returnTypes, session, null ) );
68 }
69 }
70 queryCache.put(key, cacheable);
71 }
72
73 public List get(QueryKey key, Type[] returnTypes, boolean isNaturalKeyLookup, Set spaces, SessionImplementor session)
74 throws HibernateException {
75 if ( log.isDebugEnabled() ) log.debug("checking cached query results in region: " + regionName);
76 List cacheable = (List ) queryCache.get(key);
77 if (cacheable==null) {
78 log.debug("query results were not found in cache");
79 return null;
80 }
81 List result = new ArrayList ( cacheable.size()-1 );
82 Long timestamp = (Long ) cacheable.get(0);
83 log.debug("Checking query spaces for up-to-dateness: [" + spaces + "]");
84 if ( !isNaturalKeyLookup && !isUpToDate(spaces, timestamp) ) {
85 log.debug("cached query results were not up to date");
86 return null;
87 }
88 log.debug("returning cached query results");
89 for ( int i=1; i<cacheable.size(); i++ ) {
90 if ( returnTypes.length==1 ) {
91 result.add( returnTypes[0].assemble( (Serializable ) cacheable.get(i), session, null ) );
92 }
93 else {
94 result.add( TypeFactory.assemble( (Serializable []) cacheable.get(i), returnTypes, session, null ) );
95 }
96 }
97 return result;
98 }
99
100 protected boolean isUpToDate(Set spaces, Long timestamp) {
101 return updateTimestampsCache.isUpToDate(spaces, timestamp);
102 }
103
104 public void destroy() {
105 try {
106 queryCache.destroy();
107 }
108 catch (Exception e) {
109 log.warn("could not destroy query cache: " + regionName, e);
110 }
111 }
112
113 public Cache getCache() {
114 return queryCache;
115 }
116
117 public String getRegionName() {
118 return regionName;
119 }
120
121 public String toString() {
122 return "StandardQueryCache(" + regionName + ')';
123 }
124
125 }
126 |
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