entitymanager.html

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 exists in the database.</DL>
</DD>
</DL>
<HR>

<A NAME="clear()"><!-- --></A><H3>
clear</H3>
<PRE>
void <B>clear</B>()</PRE>
<DL>
<DD>Clear the persistence context, causing all managed
 entities to become detached. Changes made to entities that
 have not been flushed to the database will not be
 persisted.
<P>
<DD><DL>

<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalStateException.html" title="class or interface in java.lang">IllegalStateException</A></CODE> - if this EntityManager has been closed.</DL>
</DD>
</DL>
<HR>

<A NAME="contains(java.lang.Object)"><!-- --></A><H3>
contains</H3>
<PRE>
boolean <B>contains</B>(<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;entity)</PRE>
<DL>
<DD>Check if the instance belongs to the current persistence
 context.
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>entity</CODE> - 
<DT><B>Returns:</B><DD><code>true</code> if the instance belongs to 
 the current persistence context.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalStateException.html" title="class or interface in java.lang">IllegalStateException</A></CODE> - if this EntityManager has been closed.
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalArgumentException.html" title="class or interface in java.lang">IllegalArgumentException</A></CODE> - if not an entity</DL>
</DD>
</DL>
<HR>

<A NAME="createQuery(java.lang.String)"><!-- --></A><H3>
createQuery</H3>
<PRE>
<A HREF="../../javax/persistence/Query.html" title="interface in javax.persistence">Query</A> <B>createQuery</B>(<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/String.html" title="class or interface in java.lang">String</A>&nbsp;qlString)</PRE>
<DL>
<DD>Create an instance of Query for executing a
 Java Persistence query language statement.
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>qlString</CODE> - a Java Persistence query language query string
<DT><B>Returns:</B><DD>the new query instance
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalStateException.html" title="class or interface in java.lang">IllegalStateException</A></CODE> - if this EntityManager has been closed.
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalArgumentException.html" title="class or interface in java.lang">IllegalArgumentException</A></CODE> - if query string is not valid</DL>
</DD>
</DL>
<HR>

<A NAME="createNamedQuery(java.lang.String)"><!-- --></A><H3>
createNamedQuery</H3>
<PRE>
<A HREF="../../javax/persistence/Query.html" title="interface in javax.persistence">Query</A> <B>createNamedQuery</B>(<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/String.html" title="class or interface in java.lang">String</A>&nbsp;name)</PRE>
<DL>
<DD>Create an instance of Query for executing a
 named query (in the Java Persistence query language or in native SQL).
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>name</CODE> - the name of a query defined in metadata
<DT><B>Returns:</B><DD>the new query instance
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalStateException.html" title="class or interface in java.lang">IllegalStateException</A></CODE> - if this EntityManager has been closed.
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalArgumentException.html" title="class or interface in java.lang">IllegalArgumentException</A></CODE> - if a query has not been
 defined with the given name</DL>
</DD>
</DL>
<HR>

<A NAME="createNativeQuery(java.lang.String)"><!-- --></A><H3>
createNativeQuery</H3>
<PRE>
<A HREF="../../javax/persistence/Query.html" title="interface in javax.persistence">Query</A> <B>createNativeQuery</B>(<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/String.html" title="class or interface in java.lang">String</A>&nbsp;sqlString)</PRE>
<DL>
<DD>Create an instance of Query for executing
 a native SQL statement, e.g., for update or delete.
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>sqlString</CODE> - a native SQL query string
<DT><B>Returns:</B><DD>the new query instance
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalStateException.html" title="class or interface in java.lang">IllegalStateException</A></CODE> - if this EntityManager has been closed.</DL>
</DD>
</DL>
<HR>

<A NAME="createNativeQuery(java.lang.String, java.lang.Class)"><!-- --></A><H3>
createNativeQuery</H3>
<PRE>
<A HREF="../../javax/persistence/Query.html" title="interface in javax.persistence">Query</A> <B>createNativeQuery</B>(<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/String.html" title="class or interface in java.lang">String</A>&nbsp;sqlString,
                        <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Class.html" title="class or interface in java.lang">Class</A>&nbsp;resultClass)</PRE>
<DL>
<DD>Create an instance of Query for executing
 a native SQL query.
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>sqlString</CODE> - a native SQL query string<DD><CODE>resultClass</CODE> - the class of the resulting instance(s)
<DT><B>Returns:</B><DD>the new query instance
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalStateException.html" title="class or interface in java.lang">IllegalStateException</A></CODE> - if this EntityManager has been closed.</DL>
</DD>
</DL>
<HR>

<A NAME="createNativeQuery(java.lang.String, java.lang.String)"><!-- --></A><H3>
createNativeQuery</H3>
<PRE>
<A HREF="../../javax/persistence/Query.html" title="interface in javax.persistence">Query</A> <B>createNativeQuery</B>(<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/String.html" title="class or interface in java.lang">String</A>&nbsp;sqlString,
                        <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/String.html" title="class or interface in java.lang">String</A>&nbsp;resultSetMapping)</PRE>
<DL>
<DD>Create an instance of Query for executing
 a native SQL query.
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>sqlString</CODE> - a native SQL query string<DD><CODE>resultSetMapping</CODE> - the name of the result set mapping
<DT><B>Returns:</B><DD>the new query instance
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalStateException.html" title="class or interface in java.lang">IllegalStateException</A></CODE> - if this EntityManager has been closed.</DL>
</DD>
</DL>
<HR>

<A NAME="joinTransaction()"><!-- --></A><H3>
joinTransaction</H3>
<PRE>
void <B>joinTransaction</B>()</PRE>
<DL>
<DD>Indicate to the EntityManager that a JTA transaction is
 active. This method should be called on a JTA application
 managed EntityManager that was created outside the scope
 of the active transaction to associate it with the current
 JTA transaction.
<P>
<DD><DL>

<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalStateException.html" title="class or interface in java.lang">IllegalStateException</A></CODE> - if this EntityManager has been closed.
<DD><CODE><A HREF="../../javax/persistence/TransactionRequiredException.html" title="class in javax.persistence">TransactionRequiredException</A></CODE> - if there is
 no transaction.</DL>
</DD>
</DL>
<HR>

<A NAME="getDelegate()"><!-- --></A><H3>
getDelegate</H3>
<PRE>
<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A> <B>getDelegate</B>()</PRE>
<DL>
<DD>Return the underlying provider object for the EntityManager,
 if available. The result of this method is implementation
 specific.
<P>
<DD><DL>

<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalStateException.html" title="class or interface in java.lang">IllegalStateException</A></CODE> - if this EntityManager has been closed.</DL>
</DD>
</DL>
<HR>

<A NAME="close()"><!-- --></A><H3>
close</H3>
<PRE>
void <B>close</B>()</PRE>
<DL>
<DD>Close an application-managed EntityManager.
 After the close method has been invoked, all methods
 on the EntityManager instance and any Query objects obtained
 from it will throw the IllegalStateException except
 for getTransaction and isOpen (which will return false).
 If this method is called when the EntityManager is
 associated with an active transaction, the persistence
 context remains managed until the transaction completes.
<P>
<DD><DL>

<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalStateException.html" title="class or interface in java.lang">IllegalStateException</A></CODE> - if the EntityManager
 is container-managed or has been already closed..</DL>
</DD>
</DL>
<HR>

<A NAME="isOpen()"><!-- --></A><H3>
isOpen</H3>
<PRE>
boolean <B>isOpen</B>()</PRE>
<DL>
<DD>Determine whether the EntityManager is open.
<P>
<DD><DL>

<DT><B>Returns:</B><DD>true until the EntityManager has been closed.</DL>
</DD>
</DL>
<HR>

<A NAME="getTransaction()"><!-- --></A><H3>
getTransaction</H3>
<PRE>
<A HREF="../../javax/persistence/EntityTransaction.html" title="interface in javax.persistence">EntityTransaction</A> <B>getTransaction</B>()</PRE>
<DL>
<DD>Returns the resource-level transaction object.
 The EntityTransaction instance may be used serially to
 begin and commit multiple transactions.
<P>
<DD><DL>

<DT><B>Returns:</B><DD>EntityTransaction instance
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalStateException.html" title="class or interface in java.lang">IllegalStateException</A></CODE> - if invoked on a JTA
    EntityManager.</DL>
</DD>
</DL>
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