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1
29
30 package com.caucho.amber.query;
31
32 import com.caucho.amber.manager.AmberConnection;
33 import com.caucho.amber.type.EntityType;
34 import com.caucho.amber.type.Type;
35 import com.caucho.bytecode.JClass;
36 import com.caucho.util.Alarm;
37
38 import java.sql.PreparedStatement  ;
39 import java.sql.ResultSet ;
40 import java.sql.SQLException ;
41 import java.util.ArrayList ;
42 import java.util.List ;
43
44
47 public class CachedQuery {
48 private SelectQuery _query;
49 private CachedQueryKey _key;
50 private ResultSetImpl _rs;
51
52 private Type []_argTypes;
53 private Object []_argValues;
54 private int _argLength = 0;
55
56 private long _loadTime;
57
58 private ArrayList <Object > _values = new ArrayList <Object >();
59
60 private volatile boolean _isLoading;
61 private volatile boolean _isValidLoad;
62
63 CachedQuery(UserQuery query)
64 {
65 _query = (SelectQuery) query.getQuery();
66
67 Type []argTypes = query.getArgTypes();
68 Object []argValues = query.getArgValues();
69
70 _argLength = query.getArgLength();
71
72 if (_argLength > 0) {
73 _argTypes = new Type[_argLength];
74 _argValues = new Object [_argLength];
75
76 for (int i = _argLength - 1; i >= 0; i--) {
77 _argTypes[i] = argTypes[i];
78 _argValues[i] = argValues[i];
79 }
80 }
81
82 _key = new CachedQueryKey();
83 _key.init(_query.getQueryString(), _argValues, _argLength);
84
85 _query.registerUpdates(this);
86 }
87
88
91 public CachedQueryKey getKey()
92 {
93 return _key;
94 }
95
96
99 public void update()
100 {
101 synchronized (this) {
102 _loadTime = 0;
103 _isValidLoad = false;
104 }
105 }
106
107
110 public void list(List <Object > list, AmberConnection aConn, long maxAge)
111 throws SQLException
112 {
113 Type type = _query.getResultType(0);
114 EntityType entityType = (EntityType) type;
115 JClass cl = entityType.getBeanClass();
116
117 synchronized (this) {
118 long now = Alarm.getCurrentTime();
119
120 if (now < _loadTime + maxAge || _isLoading && _loadTime > 0) {
121 int length = _values.size();
122
123 for (int i = 0; i < length; i++) {
124 Object key = _values.get(i);
125
126 list.add(aConn.loadLazy(cl.getName(), entityType.getName(), (java.io.Serializable ) key));
127 }
128 return;
129 }
130
131 _isLoading = true;
132 _isValidLoad = true;
133 }
134
135 try {
136 ArrayList <Object > values = new ArrayList <Object >();
137
138 ResultSetImpl rs = executeQuery(aConn);
139
140 while (rs.next()) {
141 values.add(rs.getKey(1));
142
143 list.add(rs.getObject(1));
144 }
145
146 rs.close();
147
148 synchronized (this) {
149 if (_isValidLoad) {
150 _values = values;
151
152 _loadTime = Alarm.getCurrentTime();
153 }
154 }
155 } finally {
156 _isLoading = false;
157 }
158 }
159
160
163 private ResultSetImpl executeQuery(AmberConnection aConn)
164 throws SQLException
165 {
166 if (_rs == null)
167 _rs = new ResultSetImpl();
168
169 PreparedStatement pstmt;
170 pstmt = aConn.prepareStatement(_query.getSQL());
171
172 pstmt.clearParameters();
173
174 for (int i = 0; i < _argLength; i++) {
175 if (_argValues[i] != null)
176 _argTypes[i].setParameter(pstmt, i + 1, _argValues[i]);
177 }
178
179 ResultSet rs = pstmt.executeQuery();
180
181 _rs.setResultSet(rs);
182 _rs.setQuery((SelectQuery) _query);
183 _rs.setSession(aConn);
184 _rs.init();
185
186 return _rs;
187 }
188
189 public String toString()
190 {
191 return "UserQuery[" + _query.getQueryString() + "]";
192 }
193 }
194 |
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