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<title>DiskOrderedCursor (Oracle - Berkeley DB Java Edition API)</title>
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<div class="aboutLanguage"><b>Berkeley DB Java Edition</b><br><font size=\"-1\"> version 7.5.11</font>
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<div class="subTitle">com.sleepycat.je</div>
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<h2 title="Class DiskOrderedCursor" class="title">Class DiskOrderedCursor</h2>
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<li>com.sleepycat.je.DiskOrderedCursor</li>
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<dl>
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<dt>All Implemented Interfaces:</dt>
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<dd><a href="../../../com/sleepycat/je/ForwardCursor.html" title="interface in com.sleepycat.je">ForwardCursor</a>, java.io.Closeable, java.lang.AutoCloseable</dd>
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<br>
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<pre>public class <span class="typeNameLabel">DiskOrderedCursor</span>
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extends java.lang.Object
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implements <a href="../../../com/sleepycat/je/ForwardCursor.html" title="interface in com.sleepycat.je">ForwardCursor</a></pre>
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<div class="block">DiskOrderedCursor returns records in unsorted order in exchange for
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generally faster retrieval times. Instead of key order, an approximation of
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disk order is used, which results in less I/O. This can be useful when the
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application needs to scan all records in one or more databases, and will be
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applying filtering logic which does not need key ordered retrieval.
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A DiskOrderedCursor is created using the <a href="../../../com/sleepycat/je/Database.html#openCursor-com.sleepycat.je.DiskOrderedCursorConfig-"><code>Database.openCursor(DiskOrderedCursorConfig)</code></a> method or the <a href="../../../com/sleepycat/je/Environment.html#openDiskOrderedCursor-com.sleepycat.je.Database:A-com.sleepycat.je.DiskOrderedCursorConfig-"><code>Environment.openDiskOrderedCursor(Database[], DiskOrderedCursorConfig)</code></a>
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method.
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<p>
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<em>WARNING:</em> After opening a DiskOrderedCursor, deletion of log files
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by the JE log cleaner will be disabled until <a href="../../../com/sleepycat/je/DiskOrderedCursor.html#close--"><code>close()</code></a> is called. To
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prevent unbounded growth of disk usage, be sure to call <a href="../../../com/sleepycat/je/DiskOrderedCursor.html#close--"><code>close()</code></a> to
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re-enable log file deletion.
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<p>
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<em>Optional configurations:</em> the following options are available to
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tune the DiskOrderedCursor.
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<p>
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The DiskOrderedCursor creates a background producer thread which prefetches
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some target records and inserts them in a queue for use by the cursor. The
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parameter <a href="../../../com/sleepycat/je/EnvironmentConfig.html#DOS_PRODUCER_QUEUE_TIMEOUT"><code>EnvironmentConfig.DOS_PRODUCER_QUEUE_TIMEOUT</code></a> applies to
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this background thread, and controls the timeout which governs the blocking
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queue.
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<p>
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See <a href="../../../com/sleepycat/je/DiskOrderedCursorConfig.html" title="class in com.sleepycat.je"><code>DiskOrderedCursorConfig</code></a> for additional options.
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<p>
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<h3>Consistency Guarantees</h3>
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<p>
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The consistency guarantees provided by a DiskOrderedCursor are, at best, the
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same as those provided by READ_UNCOMMITTED (see <a href="../../../com/sleepycat/je/LockMode.html" title="enum in com.sleepycat.je"><code>LockMode</code></a>). With
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READ_UNCOMMITTED, changes made by all transactions, including uncommitted
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transactions, may be returned by the scan. Also, a record returned by the
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scan is not locked, and may be modified or deleted by the application after
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it is returned, including modification or deletion of the record at the
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cursor position.
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<p>
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In other words, the records returned by the scan correspond to the state
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of the database (as if READ_UNCOMMITTED were used) at the beginning of the
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scan plus some, but not all, changes made by the application after the start
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of the scan. The user should not rely on the scan returning any changes
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made after the start of the scan. For example, if the record referred to by
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the DiskOrderedCursor is deleted after the DiskOrderedCursor is positioned
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at that record, getCurrent() will still return the key and value of that
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record and OperationStatus.SUCCESS.
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If a transactionally correct data set is required (as defined by
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READ_COMMITTED), the application must ensure that all transactions that
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write to the database are committed before the beginning of the scan.
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During the scan, no records in the database of the scan may be
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inserted, deleted, or modified. While this is possible, it is not the
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expected use case for a DiskOrderedCursor.
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<p>
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<h3>Performance Considerations</h3>
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<p>
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The internal algorithm used to approximate disk ordered reads is as follows.
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For simplicity, the algorithm description assumes that a single database is
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being scanned, but the algorithm is almost the same when multiple databases
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are involved.
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An internal producer thread is used to scan the database. This thread is
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created and started when the <code>DiskOrderedCursor</code> is created, and is
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destroyed by <a href="../../../com/sleepycat/je/DiskOrderedCursor.html#close--"><code>close()</code></a>. Scanning consists of two
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phases. In phase I the in-cache Btree of the scanned database is traversed
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in key order. The LSNs (physical record addresses) of the data to be
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fetched are accumulated in a memory buffer. Btree latches are held during
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the traversal, but only for short durations. In phase II the accumulated
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LSNs are sorted into disk order, fetched one at a time in that order, and
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the fetched data is added to a blocking queue. The <code>getNext</code> method
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in this class removes the next entry from the queue. This approach allows
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concurrent access to the Database during both phases of the scan, including
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access by the application's consumer thread (the thread calling <code>getNext</code>).
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<p>
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Phase I does not always process the entire Btree. During phase I if the
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accumulation of LSNs causes the <a href="../../../com/sleepycat/je/DiskOrderedCursorConfig.html#setInternalMemoryLimit-long-"><code>internal memory limit</code></a> or
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<a href="../../../com/sleepycat/je/DiskOrderedCursorConfig.html#setLSNBatchSize-long-"><code>LSN batch size</code></a> to be
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exceeded, phase I is ended and phase II begins. In this case, after phase
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II finishes, phase I resumes where it left off in the Btree traversal.
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Phase I and II are repeated until the entire database is scanned.
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<p>
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By default, the internal memory limit and LSN batch size are unbounded (see
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<a href="../../../com/sleepycat/je/DiskOrderedCursorConfig.html" title="class in com.sleepycat.je"><code>DiskOrderedCursorConfig</code></a>). For a database with a large number of
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records, this could cause an <code>OutOfMemoryError</code>. Therefore, it is
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strongly recommended that either the internal memory limit or LSN batch size
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is configured to limit the use of memory during the scan. On the other
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hand, the efficiency of the scan is proportional to the amount of memory
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used. If enough memory is available, the ideal case would be that the
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database is scanned in in a single iteration of phase I and II. The more
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iterations, the more random IO will occur.
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<p>
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Another factor is the <a href="../../../com/sleepycat/je/DiskOrderedCursorConfig.html#setQueueSize-int-"><code>queue
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size</code></a>. During the phase I Btree traversal, data that is resident in the JE
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cache will be added to the queue immediately, rather than waiting until
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phase II and fetching it, but only if the queue is not full. Therefore,
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increasing the size of the queue can avoid fetching data that is resident in
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the JE cache. Also, increasing the queue size can improve parallelism of
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the work done by the producer and consumer threads.
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<p>
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Also note that a <a href="../../../com/sleepycat/je/DiskOrderedCursorConfig.html#setKeysOnly-boolean-"><code>keys-only</code></a> scan
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is much more efficient than the default keys-and-data scan. With a
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keys-only scan, only the BINs (bottom internal nodes) of the Btree need to
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be fetched; the LNs (leaf nodes) do not. This is also true of databases
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<a href="../../../com/sleepycat/je/DatabaseConfig.html#setSortedDuplicates-boolean-"><code>configured for duplicates</code></a>, even
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for a keys-and-data scan, since internally the key and data are both
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contained in the BIN.</div>
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<dl>
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<dt><span class="simpleTagLabel">Since:</span></dt>
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<dd>5.0</dd>
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</dl>
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</li>
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</ul>
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</div>
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<div class="summary">
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<ul class="blockList">
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<!-- ========== METHOD SUMMARY =========== -->
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<ul class="blockList">
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<li class="blockList"><a name="method.summary">
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<!-- -->
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<h3>Method Summary</h3>
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<table class="memberSummary" border="0" cellpadding="3" cellspacing="0" summary="Method Summary table, listing methods, and an explanation">
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<caption><span id="t0" class="activeTableTab"><span>All Methods</span><span class="tabEnd"> </span></span><span id="t2" class="tableTab"><span><a href="javascript:show(2);">Instance Methods</a></span><span class="tabEnd"> </span></span><span id="t4" class="tableTab"><span><a href="javascript:show(8);">Concrete Methods</a></span><span class="tabEnd"> </span></span></caption>
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<tr>
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<th class="colFirst" scope="col">Modifier and Type</th>
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<th class="colLast" scope="col">Method and Description</th>
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</tr>
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<tr id="i0" class="altColor">
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<td class="colFirst"><code>void</code></td>
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<td class="colLast"><code><span class="memberNameLink"><a href="../../../com/sleepycat/je/DiskOrderedCursor.html#close--">close</a></span>()</code>
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<div class="block">Discards the cursor.</div>
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</td>
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</tr>
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<tr id="i1" class="rowColor">
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<td class="colFirst"><code><a href="../../../com/sleepycat/je/OperationResult.html" title="class in com.sleepycat.je">OperationResult</a></code></td>
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<td class="colLast"><code><span class="memberNameLink"><a href="../../../com/sleepycat/je/DiskOrderedCursor.html#get-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.Get-com.sleepycat.je.ReadOptions-">get</a></span>(<a href="../../../com/sleepycat/je/DatabaseEntry.html" title="class in com.sleepycat.je">DatabaseEntry</a> key,
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<a href="../../../com/sleepycat/je/DatabaseEntry.html" title="class in com.sleepycat.je">DatabaseEntry</a> data,
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||
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<a href="../../../com/sleepycat/je/Get.html" title="enum in com.sleepycat.je">Get</a> getType,
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<a href="../../../com/sleepycat/je/ReadOptions.html" title="class in com.sleepycat.je">ReadOptions</a> options)</code>
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<div class="block">Moves the cursor to a record according to the specified <a href="../../../com/sleepycat/je/Get.html" title="enum in com.sleepycat.je"><code>Get</code></a>
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type.</div>
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</td>
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||
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</tr>
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||
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<tr id="i2" class="altColor">
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||
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<td class="colFirst"><code><a href="../../../com/sleepycat/je/DiskOrderedCursorConfig.html" title="class in com.sleepycat.je">DiskOrderedCursorConfig</a></code></td>
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<td class="colLast"><code><span class="memberNameLink"><a href="../../../com/sleepycat/je/DiskOrderedCursor.html#getConfig--">getConfig</a></span>()</code>
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<div class="block">Returns this cursor's configuration.</div>
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</td>
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</tr>
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<tr id="i3" class="rowColor">
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<td class="colFirst"><code><a href="../../../com/sleepycat/je/OperationStatus.html" title="enum in com.sleepycat.je">OperationStatus</a></code></td>
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<td class="colLast"><code><span class="memberNameLink"><a href="../../../com/sleepycat/je/DiskOrderedCursor.html#getCurrent-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.LockMode-">getCurrent</a></span>(<a href="../../../com/sleepycat/je/DatabaseEntry.html" title="class in com.sleepycat.je">DatabaseEntry</a> key,
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||
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<a href="../../../com/sleepycat/je/DatabaseEntry.html" title="class in com.sleepycat.je">DatabaseEntry</a> data,
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<a href="../../../com/sleepycat/je/LockMode.html" title="enum in com.sleepycat.je">LockMode</a> lockMode)</code>
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<div class="block">Returns the key/data pair to which the cursor refers.</div>
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</td>
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</tr>
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<tr id="i4" class="altColor">
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<td class="colFirst"><code><a href="../../../com/sleepycat/je/Database.html" title="class in com.sleepycat.je">Database</a></code></td>
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||
|
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<td class="colLast"><code><span class="memberNameLink"><a href="../../../com/sleepycat/je/DiskOrderedCursor.html#getDatabase--">getDatabase</a></span>()</code>
|
||
|
|
<div class="block">Returns the Database handle for the database that contains the
|
||
|
|
latest record returned by getNext().</div>
|
||
|
|
</td>
|
||
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</tr>
|
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<tr id="i5" class="rowColor">
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<td class="colFirst"><code><a href="../../../com/sleepycat/je/OperationStatus.html" title="enum in com.sleepycat.je">OperationStatus</a></code></td>
|
||
|
|
<td class="colLast"><code><span class="memberNameLink"><a href="../../../com/sleepycat/je/DiskOrderedCursor.html#getNext-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.LockMode-">getNext</a></span>(<a href="../../../com/sleepycat/je/DatabaseEntry.html" title="class in com.sleepycat.je">DatabaseEntry</a> key,
|
||
|
|
<a href="../../../com/sleepycat/je/DatabaseEntry.html" title="class in com.sleepycat.je">DatabaseEntry</a> data,
|
||
|
|
<a href="../../../com/sleepycat/je/LockMode.html" title="enum in com.sleepycat.je">LockMode</a> lockMode)</code>
|
||
|
|
<div class="block">Moves the cursor to the next key/data pair and returns that pair.</div>
|
||
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</td>
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</tr>
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</a>
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<h3>Methods inherited from class java.lang.Object</h3>
|
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<code>clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait</code></li>
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</ul>
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</ul>
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</div>
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<div class="details">
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<ul class="blockList">
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<!-- ============ METHOD DETAIL ========== -->
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</a>
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<h3>Method Detail</h3>
|
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<a name="getDatabase--">
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</a>
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<li class="blockList">
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<h4>getDatabase</h4>
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<pre>public <a href="../../../com/sleepycat/je/Database.html" title="class in com.sleepycat.je">Database</a> getDatabase()</pre>
|
||
|
|
<div class="block">Returns the Database handle for the database that contains the
|
||
|
|
latest record returned by getNext().</div>
|
||
|
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<dl>
|
||
|
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<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
|
||
|
|
<dd><code><a href="../../../com/sleepycat/je/ForwardCursor.html#getDatabase--">getDatabase</a></code> in interface <code><a href="../../../com/sleepycat/je/ForwardCursor.html" title="interface in com.sleepycat.je">ForwardCursor</a></code></dd>
|
||
|
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<dt><span class="returnLabel">Returns:</span></dt>
|
||
|
|
<dd>The Database handle associated with this Cursor.</dd>
|
||
|
|
</dl>
|
||
|
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</li>
|
||
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</ul>
|
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<a name="close--">
|
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|
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</a>
|
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<ul class="blockList">
|
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<li class="blockList">
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<h4>close</h4>
|
||
|
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<pre>public void close()
|
||
|
|
throws <a href="../../../com/sleepycat/je/DatabaseException.html" title="class in com.sleepycat.je">DatabaseException</a></pre>
|
||
|
|
<div class="block">Discards the cursor.
|
||
|
|
|
||
|
|
<p>The cursor handle may not be used again after this method has been
|
||
|
|
called, regardless of the method's success or failure.</p>
|
||
|
|
|
||
|
|
<p>WARNING: To guard against memory leaks, the application should
|
||
|
|
discard all references to the closed handle. While BDB makes an effort
|
||
|
|
to discard references from closed objects to the allocated memory for an
|
||
|
|
environment, this behavior is not guaranteed. The safe course of action
|
||
|
|
for an application is to discard all references to closed BDB
|
||
|
|
objects.</p></div>
|
||
|
|
<dl>
|
||
|
|
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
|
||
|
|
<dd><code><a href="../../../com/sleepycat/je/ForwardCursor.html#close--">close</a></code> in interface <code><a href="../../../com/sleepycat/je/ForwardCursor.html" title="interface in com.sleepycat.je">ForwardCursor</a></code></dd>
|
||
|
|
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
|
||
|
|
<dd><code>close</code> in interface <code>java.io.Closeable</code></dd>
|
||
|
|
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
|
||
|
|
<dd><code>close</code> in interface <code>java.lang.AutoCloseable</code></dd>
|
||
|
|
<dt><span class="throwsLabel">Throws:</span></dt>
|
||
|
|
<dd><code><a href="../../../com/sleepycat/je/EnvironmentFailureException.html" title="class in com.sleepycat.je">EnvironmentFailureException</a></code> - if an unexpected, internal or
|
||
|
|
environment-wide failure occurs.</dd>
|
||
|
|
<dd><code><a href="../../../com/sleepycat/je/DatabaseException.html" title="class in com.sleepycat.je">DatabaseException</a></code></dd>
|
||
|
|
</dl>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
<a name="get-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.Get-com.sleepycat.je.ReadOptions-">
|
||
|
|
<!-- -->
|
||
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</a>
|
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<ul class="blockList">
|
||
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<li class="blockList">
|
||
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<h4>get</h4>
|
||
|
|
<pre>public <a href="../../../com/sleepycat/je/OperationResult.html" title="class in com.sleepycat.je">OperationResult</a> get(<a href="../../../com/sleepycat/je/DatabaseEntry.html" title="class in com.sleepycat.je">DatabaseEntry</a> key,
|
||
|
|
<a href="../../../com/sleepycat/je/DatabaseEntry.html" title="class in com.sleepycat.je">DatabaseEntry</a> data,
|
||
|
|
<a href="../../../com/sleepycat/je/Get.html" title="enum in com.sleepycat.je">Get</a> getType,
|
||
|
|
<a href="../../../com/sleepycat/je/ReadOptions.html" title="class in com.sleepycat.je">ReadOptions</a> options)</pre>
|
||
|
|
<div class="block"><span class="descfrmTypeLabel">Description copied from interface: <code><a href="../../../com/sleepycat/je/ForwardCursor.html#get-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.Get-com.sleepycat.je.ReadOptions-">ForwardCursor</a></code></span></div>
|
||
|
|
<div class="block">Moves the cursor to a record according to the specified <a href="../../../com/sleepycat/je/Get.html" title="enum in com.sleepycat.je"><code>Get</code></a>
|
||
|
|
type.</div>
|
||
|
|
<dl>
|
||
|
|
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
|
||
|
|
<dd><code><a href="../../../com/sleepycat/je/ForwardCursor.html#get-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.Get-com.sleepycat.je.ReadOptions-">get</a></code> in interface <code><a href="../../../com/sleepycat/je/ForwardCursor.html" title="interface in com.sleepycat.je">ForwardCursor</a></code></dd>
|
||
|
|
<dt><span class="paramLabel">Parameters:</span></dt>
|
||
|
|
<dd><code>options</code> - the ReadOptions, or null to use default options.
|
||
|
|
For DiskOrderedCursors, <a href="../../../com/sleepycat/je/ReadOptions.html#getLockMode--"><code>ReadOptions.getLockMode()</code></a> must return
|
||
|
|
null, <a href="../../../com/sleepycat/je/LockMode.html#DEFAULT"><code>LockMode.DEFAULT</code></a> or
|
||
|
|
<a href="../../../com/sleepycat/je/LockMode.html#READ_UNCOMMITTED"><code>LockMode.READ_UNCOMMITTED</code></a>, and no locking
|
||
|
|
is performed.</dd>
|
||
|
|
<dd><code>key</code> - the key returned as
|
||
|
|
<a href="DatabaseEntry.html#outParam">output</a>.</dd>
|
||
|
|
<dd><code>data</code> - the data returned as
|
||
|
|
<a href="DatabaseEntry.html#outParam">output</a>.</dd>
|
||
|
|
<dd><code>getType</code> - is <a href="../../../com/sleepycat/je/Get.html#NEXT"><code>Get.NEXT</code></a> or <a href="../../../com/sleepycat/je/Get.html#CURRENT"><code>Get.CURRENT</code></a>.
|
||
|
|
interface. <code>Get.CURRENT</code> is permitted only if the cursor is
|
||
|
|
initialized (positioned on a record).</dd>
|
||
|
|
<dt><span class="returnLabel">Returns:</span></dt>
|
||
|
|
<dd>the OperationResult if the record requested is found, else null.</dd>
|
||
|
|
</dl>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
<a name="getCurrent-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.LockMode-">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<ul class="blockList">
|
||
|
|
<li class="blockList">
|
||
|
|
<h4>getCurrent</h4>
|
||
|
|
<pre>public <a href="../../../com/sleepycat/je/OperationStatus.html" title="enum in com.sleepycat.je">OperationStatus</a> getCurrent(<a href="../../../com/sleepycat/je/DatabaseEntry.html" title="class in com.sleepycat.je">DatabaseEntry</a> key,
|
||
|
|
<a href="../../../com/sleepycat/je/DatabaseEntry.html" title="class in com.sleepycat.je">DatabaseEntry</a> data,
|
||
|
|
<a href="../../../com/sleepycat/je/LockMode.html" title="enum in com.sleepycat.je">LockMode</a> lockMode)</pre>
|
||
|
|
<div class="block"><span class="descfrmTypeLabel">Description copied from interface: <code><a href="../../../com/sleepycat/je/ForwardCursor.html#getCurrent-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.LockMode-">ForwardCursor</a></code></span></div>
|
||
|
|
<div class="block">Returns the key/data pair to which the cursor refers.
|
||
|
|
|
||
|
|
<p>Calling this method is equivalent to calling <a href="../../../com/sleepycat/je/ForwardCursor.html#get-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.Get-com.sleepycat.je.ReadOptions-"><code>ForwardCursor.get(DatabaseEntry, DatabaseEntry, Get, ReadOptions)</code></a> with
|
||
|
|
<a href="../../../com/sleepycat/je/Get.html#CURRENT"><code>Get.CURRENT</code></a>.</p></div>
|
||
|
|
<dl>
|
||
|
|
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
|
||
|
|
<dd><code><a href="../../../com/sleepycat/je/ForwardCursor.html#getCurrent-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.LockMode-">getCurrent</a></code> in interface <code><a href="../../../com/sleepycat/je/ForwardCursor.html" title="interface in com.sleepycat.je">ForwardCursor</a></code></dd>
|
||
|
|
<dt><span class="paramLabel">Parameters:</span></dt>
|
||
|
|
<dd><code>lockMode</code> - the locking attributes. For DiskOrderedCursors this
|
||
|
|
parameter must be either null, <a href="../../../com/sleepycat/je/LockMode.html#DEFAULT"><code>LockMode.DEFAULT</code></a>
|
||
|
|
or <a href="../../../com/sleepycat/je/LockMode.html#READ_UNCOMMITTED"><code>LockMode.READ_UNCOMMITTED</code></a>, and no locking
|
||
|
|
is performed.</dd>
|
||
|
|
<dd><code>key</code> - the key returned as
|
||
|
|
<a href="DatabaseEntry.html#outParam">output</a>.</dd>
|
||
|
|
<dd><code>data</code> - the data returned as
|
||
|
|
<a href="DatabaseEntry.html#outParam">output</a>.</dd>
|
||
|
|
<dt><span class="returnLabel">Returns:</span></dt>
|
||
|
|
<dd><a href="../../../com/sleepycat/je/OperationStatus.html#KEYEMPTY"><code>OperationStatus.KEYEMPTY</code></a> if there are no more records in the
|
||
|
|
DiskOrderedCursor set, otherwise, <a href="../../../com/sleepycat/je/OperationStatus.html#SUCCESS"><code>OperationStatus.SUCCESS</code></a>. If
|
||
|
|
the record referred to by a DiskOrderedCursor is deleted after the
|
||
|
|
ForwardCursor is positioned at that record, getCurrent() will still
|
||
|
|
return the key and value of that record and OperationStatus.SUCCESS.</dd>
|
||
|
|
</dl>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
<a name="getNext-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.LockMode-">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<ul class="blockList">
|
||
|
|
<li class="blockList">
|
||
|
|
<h4>getNext</h4>
|
||
|
|
<pre>public <a href="../../../com/sleepycat/je/OperationStatus.html" title="enum in com.sleepycat.je">OperationStatus</a> getNext(<a href="../../../com/sleepycat/je/DatabaseEntry.html" title="class in com.sleepycat.je">DatabaseEntry</a> key,
|
||
|
|
<a href="../../../com/sleepycat/je/DatabaseEntry.html" title="class in com.sleepycat.je">DatabaseEntry</a> data,
|
||
|
|
<a href="../../../com/sleepycat/je/LockMode.html" title="enum in com.sleepycat.je">LockMode</a> lockMode)</pre>
|
||
|
|
<div class="block"><span class="descfrmTypeLabel">Description copied from interface: <code><a href="../../../com/sleepycat/je/ForwardCursor.html#getNext-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.LockMode-">ForwardCursor</a></code></span></div>
|
||
|
|
<div class="block">Moves the cursor to the next key/data pair and returns that pair.
|
||
|
|
|
||
|
|
<p>Calling this method is equivalent to calling <a href="../../../com/sleepycat/je/ForwardCursor.html#get-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.Get-com.sleepycat.je.ReadOptions-"><code>ForwardCursor.get(DatabaseEntry, DatabaseEntry, Get, ReadOptions)</code></a> with
|
||
|
|
<a href="../../../com/sleepycat/je/Get.html#NEXT"><code>Get.NEXT</code></a>.</p></div>
|
||
|
|
<dl>
|
||
|
|
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
|
||
|
|
<dd><code><a href="../../../com/sleepycat/je/ForwardCursor.html#getNext-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.DatabaseEntry-com.sleepycat.je.LockMode-">getNext</a></code> in interface <code><a href="../../../com/sleepycat/je/ForwardCursor.html" title="interface in com.sleepycat.je">ForwardCursor</a></code></dd>
|
||
|
|
<dt><span class="paramLabel">Parameters:</span></dt>
|
||
|
|
<dd><code>lockMode</code> - the locking attributes. For DiskOrderedCursors this
|
||
|
|
parameter must be either null, <a href="../../../com/sleepycat/je/LockMode.html#DEFAULT"><code>LockMode.DEFAULT</code></a>
|
||
|
|
or <a href="../../../com/sleepycat/je/LockMode.html#READ_UNCOMMITTED"><code>LockMode.READ_UNCOMMITTED</code></a>, and no locking
|
||
|
|
is performed.</dd>
|
||
|
|
<dd><code>key</code> - the key returned as
|
||
|
|
<a href="DatabaseEntry.html#outParam">output</a>.</dd>
|
||
|
|
<dd><code>data</code> - the data returned as
|
||
|
|
<a href="DatabaseEntry.html#outParam">output</a>.</dd>
|
||
|
|
<dt><span class="returnLabel">Returns:</span></dt>
|
||
|
|
<dd><a href="../../../com/sleepycat/je/OperationStatus.html#NOTFOUND"><code>OperationStatus.NOTFOUND</code></a> if no matching key/data pair is found;
|
||
|
|
otherwise, <a href="../../../com/sleepycat/je/OperationStatus.html#SUCCESS"><code>OperationStatus.SUCCESS</code></a>.</dd>
|
||
|
|
</dl>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
<a name="getConfig--">
|
||
|
|
<!-- -->
|
||
|
|
</a>
|
||
|
|
<ul class="blockListLast">
|
||
|
|
<li class="blockList">
|
||
|
|
<h4>getConfig</h4>
|
||
|
|
<pre>public <a href="../../../com/sleepycat/je/DiskOrderedCursorConfig.html" title="class in com.sleepycat.je">DiskOrderedCursorConfig</a> getConfig()</pre>
|
||
|
|
<div class="block">Returns this cursor's configuration.
|
||
|
|
|
||
|
|
<p>This may differ from the configuration used to open this object if
|
||
|
|
the cursor existed previously.</p></div>
|
||
|
|
<dl>
|
||
|
|
<dt><span class="returnLabel">Returns:</span></dt>
|
||
|
|
<dd>This cursor's configuration.</dd>
|
||
|
|
</dl>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
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<!-- ========= END OF CLASS DATA ========= -->
|
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|
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<!-- ======= START OF BOTTOM NAVBAR ====== -->
|
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<div class="bottomNav"><a name="navbar.bottom">
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<div class="skipNav"><a href="#skip.navbar.bottom" title="Skip navigation links">Skip navigation links</a></div>
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<a name="navbar.bottom.firstrow">
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<ul class="navList" title="Navigation">
|
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<li><a href="../../../overview-summary.html">Overview</a></li>
|
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<li><a href="package-summary.html">Package</a></li>
|
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<li class="navBarCell1Rev">Class</li>
|
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<li><a href="class-use/DiskOrderedCursor.html">Use</a></li>
|
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<li><a href="package-tree.html">Tree</a></li>
|
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<li><a href="../../../deprecated-list.html">Deprecated</a></li>
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|
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<li><a href="../../../help-doc.html">Help</a></li>
|
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</ul>
|
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<div class="aboutLanguage"><b>Berkeley DB Java Edition</b><br><font size=\"-1\"> version 7.5.11</font>
|
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</div>
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</div>
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<div class="subNav">
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<ul class="navList">
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<li><a href="../../../com/sleepycat/je/DiskLimitException.html" title="class in com.sleepycat.je"><span class="typeNameLink">Prev Class</span></a></li>
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<li><a href="../../../com/sleepycat/je/DiskOrderedCursorConfig.html" title="class in com.sleepycat.je"><span class="typeNameLink">Next Class</span></a></li>
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<li><a href="../../../index.html?com/sleepycat/je/DiskOrderedCursor.html" target="_top">Frames</a></li>
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<li><a href="../../../allclasses-noframe.html">All Classes</a></li>
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<script type="text/javascript"><!--
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allClassesLink = document.getElementById("allclasses_navbar_bottom");
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if(window==top) {
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allClassesLink.style.display = "block";
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