Adding JMCR-Stable version

[Benchmarks_CSolver.git] / JMCR-Stable / real-world application / derby-10.3.2.1 / java / engine / org / apache / derby / iapi / store / raw / ContainerLock.java

diff --git a/JMCR-Stable/real-world application/derby-10.3.2.1/java/engine/org/apache/derby/iapi/store/raw/ContainerLock.java b/JMCR-Stable/real-world application/derby-10.3.2.1/java/engine/org/apache/derby/iapi/store/raw/ContainerLock.java
new file mode 100644 (file)
index 0000000..1722e10
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+++ b/JMCR-Stable/real-world application/derby-10.3.2.1/java/engine/org/apache/derby/iapi/store/raw/ContainerLock.java
@@ -0,0 +1,108 @@
+/*\r
+\r
+   Derby - Class org.apache.derby.iapi.store.raw.ContainerLock\r
+\r
+   Licensed to the Apache Software Foundation (ASF) under one or more\r
+   contributor license agreements.  See the NOTICE file distributed with\r
+   this work for additional information regarding copyright ownership.\r
+   The ASF licenses this file to you under the Apache License, Version 2.0\r
+   (the "License"); you may not use this file except in compliance with\r
+   the License.  You may obtain a copy of the License at\r
+\r
+      http://www.apache.org/licenses/LICENSE-2.0\r
+\r
+   Unless required by applicable law or agreed to in writing, software\r
+   distributed under the License is distributed on an "AS IS" BASIS,\r
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
+   See the License for the specific language governing permissions and\r
+   limitations under the License.\r
+\r
+ */\r
+\r
+package org.apache.derby.iapi.store.raw;\r
+\r
+/**\r
+       A ContainerLock represents a qualifier that is to be used when\r
+       locking a container through a ContainerHandle.\r
+\r
+       <BR>\r
+       MT - Immutable\r
+\r
+       @see ContainerHandle\r
+       @see LockingPolicy\r
+*/\r
+\r
+public final class ContainerLock {\r
+\r
+       /** Integer representation of the type of the lock. */\r
+       private final int type;\r
+       /** Bit mask with one bit set. The position of the bit tells the type of\r
+        * the lock. */\r
+       private final int typeBit;\r
+       /** Bit mask which represents the lock types that are compatible with this\r
+        * lock type. */\r
+       private final int compat;\r
+\r
+       /** Number of types of container locks. */\r
+       public static final int C_NUMBER = 5;\r
+\r
+       /** Container lock compatibility table. */\r
+       private static final boolean[][] C_COMPAT = {\r
+\r
+       //                          Granted\r
+       // Request \    CIS             CIX             CS              CU              CX        \r
+       //      \r
+       /* CIS  */  {   true,   true,   true,   false,  false    },\r
+       /* CIX  */  {   true,   true,   false,  false,  false    },\r
+       /* CS   */  {   true,   false,  true,   false,  false    },\r
+       /* CU   */      {       false,  false,  true,   false,  false    },\r
+       /* CX   */  {   false,  false,  false,  false,  false    }\r
+\r
+       };\r
+\r
+       private ContainerLock(int type) {\r
+               this.type = type;\r
+               typeBit = (1 << type);\r
+               int bitmask = 0;\r
+               for (int i = 0; i < C_NUMBER; i++) {\r
+                       // set a bit in bitmask for each compatible lock type\r
+                       if (C_COMPAT[type][i]) {\r
+                               bitmask |= (1 << i);\r
+                       }\r
+               }\r
+               compat = bitmask;\r
+       }\r
+\r
+    // Names of locks for virtual lock table print out\r
+       private static String[] shortnames = {"IS", "IX", "S", "U", "X" };\r
+\r
+       /** Container Intent Shared lock  */\r
+       public static final ContainerLock CIS = new ContainerLock(0);\r
+       /**     Container Intent Exclusive lock */\r
+       public static final ContainerLock CIX = new ContainerLock(1);\r
+       /**  Container Shared lock */\r
+       public static final ContainerLock CS  = new ContainerLock(2);\r
+       /** Container Update lock */\r
+       public static final ContainerLock CU  = new ContainerLock(3);\r
+       /** Container Exclusive lock */\r
+       public static final ContainerLock CX  = new ContainerLock(4);\r
+\r
+       /**\r
+               Get an integer representation of the type of the lock. This method is guaranteed\r
+               to return an integer >= 0 and < C_NUMBER. No correlation between the value\r
+               and one of the static variables (CIS etc.) is guaranteed, except that\r
+               the values returned do not change.\r
+       */\r
+       public int getType() {\r
+               return type;\r
+       }\r
+\r
+       public boolean isCompatible(ContainerLock granted) {\r
+               return (granted.typeBit & compat) != 0;\r
+       }\r
+\r
+       public String toString() {\r
+\r
+               return shortnames[getType()];\r
+       }\r
+}\r