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1
50 package org.apache.avalon.excalibur.pool;
51
52 import org.apache.avalon.framework.activity.Disposable;
53
54
64 public class DefaultPool
65 extends AbstractPool
66 implements Disposable
67 {
68 protected int m_min;
69 protected int m_max;
70 protected PoolController m_controller;
71 protected boolean m_disposed = false;
72 protected boolean m_quickFail = false;
73
74 public DefaultPool( final ObjectFactory factory,
75 final PoolController controller )
76 throws Exception 
77 {
78 this( factory, controller, AbstractPool.DEFAULT_POOL_SIZE, AbstractPool.DEFAULT_POOL_SIZE );
79 }
80
81 public DefaultPool( final ObjectFactory factory,
82 final PoolController controller,
83 final int initial,
84 final int maximum )
85 throws Exception
86 {
87 super( factory );
88
89 int t_max = maximum;
90 int t_min = initial;
91
92 if( t_min < 0 )
93 {
94 if( null != getLogger() && getLogger().isWarnEnabled() )
95 {
96 getLogger().warn( "Minumum number of poolables specified is " +
97 "less than 0, using 0" );
98 }
99
100 t_min = 0;
101 }
102
103 if( ( t_max < t_min ) || ( t_max < 1 ) )
104 {
105 if( null != getLogger() && getLogger().isWarnEnabled() )
106 {
107 getLogger().warn( "Maximum number of poolables specified must be at " +
108 "least 1 and must be greater than the minumum number " +
109 "of connections" );
110 }
111 t_max = ( t_min > 1 ) ? t_min : 1;
112 }
113
114 m_max = t_max;
115 m_min = t_min;
116
117 if( null != controller )
118 {
119 m_controller = controller;
120 }
121 else
122 {
123 m_controller = new DefaultPoolController( t_min / 2 );
124 }
125 }
126
127 public DefaultPool( final ObjectFactory factory )
128 throws Exception
129 {
130 this( factory, null, AbstractPool.DEFAULT_POOL_SIZE, AbstractPool.DEFAULT_POOL_SIZE );
131 }
132
133 public DefaultPool( final Class clazz, final int initial, final int maximum )
134 throws NoSuchMethodException , Exception
135 {
136 this( new DefaultObjectFactory( clazz ), null, initial, maximum );
137 }
138
139 public DefaultPool( final Class clazz, final int initial )
140 throws NoSuchMethodException , Exception
141 {
142 this( clazz, initial, initial );
143 }
144
145 public Poolable get() throws Exception
146 {
147 Poolable obj = null;
148
149 if( !m_initialized )
150 {
151 throw new IllegalStateException ( "You cannot get a Poolable before the pool is initialized" );
152 }
153
154 if( m_disposed )
155 {
156 throw new IllegalStateException ( "You cannot get a Poolable after the pool is disposed" );
157 }
158
159 m_mutex.acquire();
160 try
161 {
162 if( m_ready.size() == 0 )
163 {
164 if( this instanceof Resizable )
165 {
166 this.internalGrow( m_controller.grow() );
167
168 if( m_ready.size() > 0 )
169 {
170 obj = (Poolable)m_ready.remove();
171 }
172 else
173 {
174 final String message =
175 "Could not create enough Components to service " +
176 "your request.";
177 throw new Exception ( message );
178 }
179 }
180 else
181 {
182 obj = newPoolable();
183 }
184 }
185 else
186 {
187 obj = (Poolable)m_ready.remove();
188 }
189
190 m_active.add( obj );
191
192 if( getLogger().isDebugEnabled() )
193 {
194 final String message = "Retrieving a " +
195 m_factory.getCreatedClass().getName() + " from the pool";
196 getLogger().debug( message );
197 }
198 return obj;
199 }
200 finally
201 {
202 m_mutex.release();
203 }
204 }
205
206 public void put( final Poolable obj )
207 {
208 if( !m_initialized )
209 {
210 final String message = "You cannot get a Poolable before " +
211 "the pool is initialized";
212 throw new IllegalStateException ( message );
213 }
214
215 try
216 {
217 if( obj instanceof Recyclable )
218 {
219 ( (Recyclable)obj ).recycle();
220 }
221
222 m_mutex.acquire();
223 try
224 {
225 m_active.remove( m_active.indexOf( obj ) );
226
227 if( getLogger().isDebugEnabled() )
228 {
229 final String message =
230 "Returning a " + m_factory.getCreatedClass().getName() +
231 " to the pool";
232 getLogger().debug( message );
233 }
234
235 if( m_disposed == false )
236 {
237 m_ready.add( obj );
238
239 if( ( this.size() > m_max ) && ( this instanceof Resizable ) )
240 {
241 this.internalShrink( m_controller.shrink() );
242 }
243 }
244 else
245 {
246 this.removePoolable( obj );
247 }
248 }
249 finally
250 {
251 m_mutex.release();
252 }
253 }
254 catch( Exception e )
255 {
256 if( getLogger().isWarnEnabled() )
257 {
258 getLogger().warn( "Pool interrupted while waiting for lock.", e );
259 }
260 }
261 }
262
263 public final void dispose()
264 {
265 try
266 {
267 m_mutex.acquire();
268 try
269 {
270 while( m_ready.size() > 0 )
271 {
272 this.removePoolable( (Poolable)m_ready.remove() );
273 }
274 }
275 finally
276 {
277 m_mutex.release();
278 }
279 }
280 catch( Exception e )
281 {
282 if( getLogger().isWarnEnabled() )
283 {
284 getLogger().warn( "Caught an exception disposing of pool", e );
285 }
286 }
287
288 this.m_disposed = true;
289 }
290 }
291 |
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