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<title>Berkeley DB: DbMultipleDataIterator</title>
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<h1>DbMultipleDataIterator</h1>
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<h3><pre>
import com.sleepycat.db.*;
<p>
public class DbMultipleDataIterator
{
public DbMultipleDataIterator(Dbt data);
<p>
public boolean next(Dbt data);
}
<p>
public class DbMultipleKeyDataIterator
{
public DbMultipleKeyDataIterator(Dbt data);
<p>
public boolean next(Dbt key, Dbt data);
}
<p>
public class DbMultipleRecnoDataIterator
{
public DbMultipleRecnoDataIterator(Dbt data);
<p>
public boolean next(Dbt key, Dbt data);
}
</pre></h3>
<h1>Description</h1>
<p>If either of the <a href="../api_java/dbc_get.html#DB_MULTIPLE">Db.DB_MULTIPLE</a> or <a href="../api_java/dbc_get.html#DB_MULTIPLE_KEY">Db.DB_MULTIPLE_KEY</a> flags
were specified to the <a href="../api_java/db_get.html">Db.get</a> or <a href="../api_java/dbc_get.html">Dbc.get</a> method, the data
<a href="../api_java/dbt_class.html">Dbt</a> returned by those interfaces will refer to a buffer that
is filled with data. Access to that data is through the following
classes.
<p>All instances of the bulk retrieval classes may be used only once,
and to traverse the bulk retrieval buffer in the forward direction
only. However, they are nondestructive, so multiple iterators can be
instantiated and used on the same returned data <a href="../api_java/dbt_class.html">Dbt</a>.
<p><dl compact>
<p><dt>DbMultipleDataIterator<dd>This class is used to iterate through data returned using the
<a href="../api_java/dbc_get.html#DB_MULTIPLE">Db.DB_MULTIPLE</a> flag from a database belonging to any access method.
The constructor takes the data <a href="../api_java/dbt_class.html">Dbt</a> returned by the call to
<a href="../api_java/db_get.html">Db.get</a> or <a href="../api_java/dbc_get.html">Dbc.get</a> that used the <a href="../api_java/dbc_get.html#DB_MULTIPLE">Db.DB_MULTIPLE</a>
flag. The next() method takes a <a href="../api_java/dbt_class.html">Dbt</a> that will be filled in with
a reference to a buffer, a size, and an offset that together yield the
next data item in the original bulk retrieval buffer. The next() method
returns false if no more data are available, and true otherwise.
<p><dt>DbMultipleKeyDataIterator<dd>This class is used to iterate through data returned using the
<a href="../api_java/dbc_get.html#DB_MULTIPLE_KEY">Db.DB_MULTIPLE_KEY</a> flag from a database belonging to the Btree or
Hash access methods. The constructor takes the data <a href="../api_java/dbt_class.html">Dbt</a>
returned by the call to <a href="../api_java/db_get.html">Db.get</a> or <a href="../api_java/dbc_get.html">Dbc.get</a> that used the
<a href="../api_java/dbc_get.html#DB_MULTIPLE_KEY">Db.DB_MULTIPLE_KEY</a> flag. The next() method takes two <a href="../api_java/dbt_class.html">Dbt</a>s,
one for a key and one for a data item, that will each be filled in with
a reference to a buffer, a size, and an offset that together yield the
next key or data item in the original bulk retrieval buffer. The next()
method returns false if no more data are available, and true
otherwise.
<p><dt>DbMultipleRecnoDataIterator<dd>This class is used to iterate through data returned using the
<a href="../api_java/dbc_get.html#DB_MULTIPLE_KEY">Db.DB_MULTIPLE_KEY</a> flag from a database belonging to the Recno or
Queue access methods. The constructor takes the data <a href="../api_java/dbt_class.html">Dbt</a>
returned by the call to <a href="../api_java/db_get.html">Db.get</a> or <a href="../api_java/dbc_get.html">Dbc.get</a> that used the
<a href="../api_java/dbc_get.html#DB_MULTIPLE_KEY">Db.DB_MULTIPLE_KEY</a> flag. The next() method takes two <a href="../api_java/dbt_class.html">Dbt</a>s,
one for a key and one for a data item, that will each be filled in with
a reference to a buffer, a size, and an offset that together yield the
next key or data item in the original bulk retrieval buffer. The record
number contained in the key item should be accessed using the
<a href="../api_java/dbt_class.html">Dbt.get_recno_key_data</a> method. The next() method returns false if no
more data are available, and true otherwise.
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