Coverage Report - org.apache.ojb.broker.locking.LockManager
 
Classes in this File Line Coverage Branch Coverage Complexity
LockManager
N/A
N/A
1
 
 1  
 package org.apache.ojb.broker.locking;
 2  
 
 3  
 /* Copyright 2002-2005 The Apache Software Foundation
 4  
  *
 5  
  * Licensed under the Apache License, Version 2.0 (the "License");
 6  
  * you may not use this file except in compliance with the License.
 7  
  * You may obtain a copy of the License at
 8  
  *
 9  
  *     http://www.apache.org/licenses/LICENSE-2.0
 10  
  *
 11  
  * Unless required by applicable law or agreed to in writing, software
 12  
  * distributed under the License is distributed on an "AS IS" BASIS,
 13  
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 14  
  * See the License for the specific language governing permissions and
 15  
  * limitations under the License.
 16  
  */
 17  
 
 18  
 
 19  
 /**
 20  
  * This interface declares the functionality of the OJB locking-api for support of
 21  
  * pessimistic locking.
 22  
  * <p>
 23  
  * OJB allows to provide user defined implementations of this interface.
 24  
  * To activate a user defined LockManager implementation it must be configured in
 25  
  * the OJB.properties file.
 26  
  * </p>
 27  
  * <p>
 28  
  * All locks have to be reentrant, this means if you already have a lock for
 29  
  * writing and you try to acquire write access again you will not be blocked
 30  
  * by this first lock.
 31  
  * </p>
 32  
  * <p>
 33  
  * It's optional to support the <em>lockTimeout</em> and <em>blockTimeout</em> properties.
 34  
  * </p>
 35  
  *
 36  
  * @see LockManagerInMemoryImpl
 37  
  * @see LockManagerCommonsImpl
 38  
  * @version $Id: LockManager.java,v 1.1 2007-08-24 22:17:41 ewestfal Exp $
 39  
  */
 40  
 public interface LockManager extends IsolationLevels
 41  
 {
 42  
     /**
 43  
      * Default lock timeout value - set to 60000 ms.
 44  
      */
 45  
     public final static long DEFAULT_LOCK_TIMEOUT = 60000;
 46  
 
 47  
     /**
 48  
      * Default lock wait time in millisecond - set to 1000 ms;
 49  
      */
 50  
     public final static long DEFAULT_BLOCK_TIMEOUT = 1000;
 51  
 
 52  
     /**
 53  
      * The maximal time to wait for acquire a lock.
 54  
      *
 55  
      * @return
 56  
      */
 57  
     public long getBlockTimeout();
 58  
 
 59  
     /**
 60  
      * Set the maximal time to wait for acquire a lock in milliseconds.
 61  
      * All so called <em>non-blocking</em> implementation will ignore this setting.
 62  
      *
 63  
      * @param timeout The time to wait for acquire a lock.
 64  
      */
 65  
     public void setBlockTimeout(long timeout);
 66  
 
 67  
     /**
 68  
      * Get the current used lock timeout value in milliseconds.
 69  
      * @return Current used locking timeout value in ms.
 70  
      */
 71  
     public long getLockTimeout();
 72  
 
 73  
     /**
 74  
      * Set the lock timeout value in milliseconds. If timeout was set to <em>-1</em>
 75  
      * the never will never timeout.
 76  
      *
 77  
      * @param timeout The lock timeout in <em>ms</em> of acquired read/write/upgrade locks.
 78  
       */
 79  
     public void setLockTimeout(long timeout);
 80  
 
 81  
     /**
 82  
      * Returns info about the used lock manager implementation and the state
 83  
      * of the lock manager.
 84  
      */
 85  
     public String getLockInfo();
 86  
 
 87  
     /**
 88  
      * Acquires a readlock for lock key on resource object.
 89  
      * Returns true if successful, else false.
 90  
      *
 91  
      * @param key            The owner key of the lock.
 92  
      * @param resourceId     The resource to lock.
 93  
      * @param isolationLevel The isolation level of the lock.
 94  
      * @return <em>True</em> if the lock was successfully acquired.
 95  
      */
 96  
     public boolean readLock(Object key, Object resourceId, int isolationLevel);
 97  
 
 98  
     /**
 99  
      * Acquires a write lock for lock key on resource object.
 100  
      * Returns true if successful, else false.
 101  
      *
 102  
      * @param key            The owner key of the lock.
 103  
      * @param resourceId     The resource to lock.
 104  
      * @param isolationLevel The isolation level of the lock.
 105  
      * @return <em>True</em> if the lock was successfully acquired.
 106  
      */
 107  
     public boolean writeLock(Object key, Object resourceId, int isolationLevel);
 108  
 
 109  
     /**
 110  
      * Acquire an upgrade lock.
 111  
      * (Current implementations always acquire a write lock instead).
 112  
      *
 113  
      * @param key            The owner key of the lock.
 114  
      * @param resourceId     The resource to lock.
 115  
      * @param isolationLevel The isolation level of the lock.
 116  
      * @return <em>True</em> if the lock was successfully acquired.
 117  
      */
 118  
     public boolean upgradeLock(Object key, Object resourceId, int isolationLevel);
 119  
 
 120  
     /**
 121  
      * Releases a lock for lock key on resource object.
 122  
      * Returns true if successful, else false.
 123  
      *
 124  
      * @param key            The owner key of the lock.
 125  
      * @param resourceId     The resource to release.
 126  
      * @return <em>True</em> if the lock was successfully released.
 127  
      */
 128  
     public boolean releaseLock(Object key, Object resourceId);
 129  
 
 130  
     /**
 131  
      * Release all resource locks hold by the specified owner key.
 132  
      *
 133  
      * @param key The owner key to release all associated locks.
 134  
      */
 135  
     public void releaseLocks(Object key);
 136  
 
 137  
     /**
 138  
      * Checks if there is a read lock for owner key on resource object.
 139  
      * Returns true if so, else false.
 140  
      *
 141  
      * @param key            The owner key of the lock.
 142  
      * @param resourceId     The resource to check.
 143  
      * @return <em>True</em> if the lock exists.
 144  
      */
 145  
     public boolean hasRead(Object key, Object resourceId);
 146  
 
 147  
     /**
 148  
      * Checks if there is a write lock for lock key on resource object.
 149  
      * Returns true if so, else false.
 150  
      *
 151  
      * @param key            The owner key of the lock.
 152  
      * @param resourceId     The resource to check.
 153  
      * @return <em>True</em> if the lock exists.
 154  
      */
 155  
     public boolean hasWrite(Object key, Object resourceId);
 156  
 
 157  
     /**
 158  
      * Checks if there is a upgrade lock for lock key on resource object.
 159  
      * Returns true if so, else false.
 160  
      *
 161  
      * @param key            The owner key of the lock.
 162  
      * @param resourceId     The resource to check.
 163  
      * @return <em>True</em> if the lock exists.
 164  
      */
 165  
     public boolean hasUpgrade(Object key, Object resourceId);
 166  
 }