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<h1>DbEnv.set_lk_detect</h1>
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<h3><pre>
import com.sleepycat.db.*;
<p>
public void set_lk_detect(int detect)
throws DbException;
</pre></h3>
<h1>Description</h1>
<p>Set if the deadlock detector is to be run whenever a lock conflict
occurs, and specify what lock request(s) should be rejected. As
transactions acquire locks on behalf of a single locker ID, rejecting
a lock request associated with a transaction normally requires the
transaction be aborted. The specified value must be one of the
following list:
<p><dl compact>
<p><dt><a name="Db.DB_LOCK_DEFAULT">Db.DB_LOCK_DEFAULT</a><dd>Use whatever lock policy was specified when the database environment
was created. If no lock policy has yet been specified, set the lock
policy to Db.DB_LOCK_RANDOM.
<dt><a name="Db.DB_LOCK_EXPIRE">Db.DB_LOCK_EXPIRE</a><dd>Reject lock requests which have timed out. No other deadlock detection
is performed.
<dt><a name="Db.DB_LOCK_MAXLOCKS">Db.DB_LOCK_MAXLOCKS</a><dd>Reject the lock request for the locker ID with the greatest number of
locks.
<dt><a name="Db.DB_LOCK_MINLOCKS">Db.DB_LOCK_MINLOCKS</a><dd>Reject the lock request for the locker ID with the fewest number of
locks.
<dt><a name="Db.DB_LOCK_MINWRITE">Db.DB_LOCK_MINWRITE</a><dd>Reject the lock request for the locker ID with the fewest number of
write locks.
<dt><a name="Db.DB_LOCK_OLDEST">Db.DB_LOCK_OLDEST</a><dd>Reject the lock request for the oldest locker ID.
<dt><a name="Db.DB_LOCK_RANDOM">Db.DB_LOCK_RANDOM</a><dd>Reject the lock request for a random locker ID.
<dt><a name="Db.DB_LOCK_YOUNGEST">Db.DB_LOCK_YOUNGEST</a><dd>Reject the lock request for the youngest locker ID.
</dl>
<p>The DbEnv.set_lk_detect interface may be used only to configure Berkeley DB before
the <a href="../../db4-devel-4.0.14/api_java/env_open.html">DbEnv.open</a> interface is called.
<p>The DbEnv.set_lk_detect method throws an exception that encapsulates a non-zero error value on
failure.
<p>The database environment's deadlock detector configuration may also be set using the environment's
<b>DB_CONFIG</b> file. The syntax of the entry in that file is a
single line with the string "set_lk_detect", one or more whitespace characters,
and the interface <b>detect</b> argument as a string; for example,
"set_lk_detect DB_LOCK_OLDEST". Because the <b>DB_CONFIG</b> file is read when the database
environment is opened, it will silently overrule configuration done
before that time.
<h1>Errors</h1>
<p>The DbEnv.set_lk_detect method may fail and throw an exception encapsulating a non-zero error for the following conditions:
<p><dl compact>
<p><dt>EINVAL<dd>An invalid flag value or parameter was specified.
<p>Called after <a href="../../db4-devel-4.0.14/api_java/env_open.html">DbEnv.open</a> was called.
</dl>
<p>The DbEnv.set_lk_detect method may fail and throw an exception for errors specified for other Berkeley DB and C library or system methods.
If a catastrophic error has occurred, the DbEnv.set_lk_detect method may fail and throw
a <a href="../../db4-devel-4.0.14/api_java/runrec_class.html">DbRunRecoveryException</a>, in which case all subsequent Berkeley DB calls
will fail in the same way.
<h1>Class</h1>
<a href="../../db4-devel-4.0.14/api_java/dbenv_class.html">DbEnv</a>, <a href="../../db4-devel-4.0.14/api_java/lock_class.html">DbLock</a>
<h1>See Also</h1>
<a href="../../db4-devel-4.0.14/api_java/env_set_lk_conflicts.html">DbEnv.set_lk_conflicts</a>,
<a href="../../db4-devel-4.0.14/api_java/env_set_lk_detect.html">DbEnv.set_lk_detect</a>,
<a href="../../db4-devel-4.0.14/api_java/env_set_lk_max_lockers.html">DbEnv.set_lk_max_lockers</a>,
<a href="../../db4-devel-4.0.14/api_java/env_set_lk_max_locks.html">DbEnv.set_lk_max_locks</a>,
<a href="../../db4-devel-4.0.14/api_java/env_set_lk_max_objects.html">DbEnv.set_lk_max_objects</a>,
<a href="../../db4-devel-4.0.14/api_java/lock_detect.html">DbEnv.lock_detect</a>,
<a href="../../db4-devel-4.0.14/api_java/lock_get.html">DbEnv.lock_get</a>,
<a href="../../db4-devel-4.0.14/api_java/lock_id.html">DbEnv.lock_id</a>,
<a href="../../db4-devel-4.0.14/api_java/lock_id_free.html">DbEnv.lock_id_free</a>,
<a href="../../db4-devel-4.0.14/api_java/lock_put.html">DbEnv.lock_put</a>,
and
<a href="../../db4-devel-4.0.14/api_java/lock_stat.html">DbEnv.lock_stat</a>.
</tt>
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