Package com.saxonica.xqj

Class SaxonXQConnection

  • All Implemented Interfaces:
    XQConnection, XQDataFactory
    public class SaxonXQConnection
extends SaxonXQDataFactory
implements XQConnection
    Saxon implementation of the XQL interface XQConnection. This interface represents a "connection" between an XQuery application and an XQuery server. In Saxon the client and server run in the same process so the concept of a connection is rather notional, and some of the properties have little meaning. However, the connection is the factory object used to compile queries.

    For Javadoc descriptions of the public methods, see the XQJ documentation.

    • Method Detail

      • getConfiguration

        public Configuration getConfiguration()
        Get the Saxon Configuration in use. Changes made to this Configuration will affect this data source and XQJ connections created from it (either before or afterwards).
        Returns:
        the configuration in use.

      • commit

        public void commit()
            throws XQException
        Description copied from interface: XQConnection
        Makes all changes made in the current transaction permanent and releases any locks held by the datasource. This method should be used only when auto-commit mode is disabled.

        Any XQResultSequence, or XQResultItem may be implicitly closed upon commit, if the holdability property of the sequence is set to XQConstants.HOLDTYPE_CLOSE_CURSORS_AT_COMMIT.

        Specified by:
        commit in interface XQConnection
        Throws:
        XQException - if the connection is in a closed state or this connection is operating in auto-commit mode

      • createExpression

        public XQExpression createExpression()
                              throws XQException
        Description copied from interface: XQConnection
        Creates a new XQExpression object that can be used to perform execute immediate operations with XQuery expressions. The properties of the connection's default XQStaticContext are copied to the returned XQExpression.
        Specified by:
        createExpression in interface XQConnection
        Returns:
        XQExpression that can be used to execute multiple expressions
        Throws:
        XQException - if the connection is in a closed state

      • createExpression

        public XQExpression createExpression​(XQStaticContext properties)
                              throws XQException
        Description copied from interface: XQConnection
        Creates a new XQExpression object that can be used to perform execute immediate operations with XQuery expressions. The properties of the specified XQStaticContext values are copied to the returned XQExpression.
        Specified by:
        createExpression in interface XQConnection
        Parameters:
        properties - XQStaticContext containing values of expression properties
        Returns:
        XQExpression that can be used to execute multiple expressions
        Throws:
        XQException - if (1) the connection is in a closed state, or (2) the specified argument is null

      • getAutoCommit

        public boolean getAutoCommit()
        Description copied from interface: XQConnection
        Gets the auto-commit attribute of this connection
        Specified by:
        getAutoCommit in interface XQConnection
        Returns:
        the auto-commit attribute of this connection. true if the connection operates in auto-commit mode; otherwise false

      • getStaticContext

        public XQStaticContext getStaticContext()
                                 throws XQException
        Description copied from interface: XQConnection
        Gets an XQStaticContext representing the default values for all expression properties. In order to modify the defaults, it is not sufficient to modify the values in the returned XQStaticContext object; in addition setStaticContext should be called to make those new values effective.
        Specified by:
        getStaticContext in interface XQConnection
        Returns:
        XQStaticContext representing the default values for all expression properties
        Throws:
        XQException - if the connection is in a closed state

      • prepareExpression

        public XQPreparedExpression prepareExpression​(java.io.InputStream xquery)
                                       throws XQException
        Description copied from interface: XQConnection
        Prepares an expression for execution.

        The properties of the connection's default XQStaticContext are copied to the returned XQPreparedExpression.

        Specified by:
        prepareExpression in interface XQConnection
        Parameters:
        xquery - the XQuery expression as an InputStream. Cannot be null
        Returns:
        the prepared XQuery expression
        Throws:
        XQException - if (1) the connection is in a closed state, (2) there are errors preparing the expression or (3) the xquery parameter is null

      • prepareExpression

        public XQPreparedExpression prepareExpression​(java.io.InputStream xquery,
                                              XQStaticContext properties)
                                       throws XQException
        Description copied from interface: XQConnection
        Prepares an expression for execution.

        The properties of the specified XQStaticContext values are copied to the returned XQPreparedExpression.

        Specified by:
        prepareExpression in interface XQConnection
        Parameters:
        xquery - the XQuery expression as an InputStream. Cannot be null
        properties - XQStaticContext containing values of expression properties
        Returns:
        the prepared XQuery expression
        Throws:
        XQException - if (1) the connection is in a closed state, or (2) the specified argument is null

      • prepareExpression

        public XQPreparedExpression prepareExpression​(java.io.Reader xquery)
                                       throws XQException
        Description copied from interface: XQConnection
        Prepares an expression for execution.

        The properties of the connection's default XQStaticContext are copied to the returned XQPreparedExpression.

        Specified by:
        prepareExpression in interface XQConnection
        Parameters:
        xquery - the XQuery expression as a Reader. Cannot be null
        Returns:
        the prepared XQuery expression
        Throws:
        XQException - if (1) the connection is in a closed state, (2) there are errors preparing the expression, or (3) the xquery parameter is null

      • prepareExpression

        public XQPreparedExpression prepareExpression​(java.io.Reader xquery,
                                              XQStaticContext properties)
                                       throws XQException
        Description copied from interface: XQConnection
        Prepares an expression for execution.

        The properties of the specified XQStaticContext values are copied to the returned XQPreparedExpression.

        Specified by:
        prepareExpression in interface XQConnection
        Parameters:
        xquery - the XQuery expression as a Reader. Cannot be null
        properties - XQStaticContext containing values of expression properties
        Returns:
        the prepared XQuery expression
        Throws:
        XQException - if (1) the connection is in a closed state, or (2) the specified argument is null

      • prepareExpression

        public XQPreparedExpression prepareExpression​(java.lang.String xquery)
                                       throws XQException
        Description copied from interface: XQConnection
        Prepares an expression for execution.

        The properties of the connection's default XQStaticContext are copied to the returned XQPreparedExpression.

        Specified by:
        prepareExpression in interface XQConnection
        Parameters:
        xquery - the XQuery expression as a String. Cannot be null
        Returns:
        the prepared XQuery expression
        Throws:
        XQException - if (1) the connection is in a closed state, (2) there are errors preparing the expression, or (3) the xquery parameter is null

      • prepareExpression

        public XQPreparedExpression prepareExpression​(java.lang.String xquery,
                                              XQStaticContext properties)
                                       throws XQException
        Description copied from interface: XQConnection
        Prepares an expression for execution.

        The properties of the specified XQStaticContext values are copied to the returned XQPreparedExpression.

        Specified by:
        prepareExpression in interface XQConnection
        Parameters:
        xquery - the XQuery expression as a String. Cannot be null
        properties - XQStaticContext containing values of expression properties.
        Returns:
        the prepared XQuery expression
        Throws:
        XQException - if (1) the connection is in a closed state, or (2) the specified argument is null

      • copyPreparedExpression

        public XQPreparedExpression copyPreparedExpression​(XQPreparedExpression expression)
                                            throws XQException
        Copy a prepared expression to create a new prepared expression. The prepared expression to be copied may belong to a different connection. This method (which is a Saxon extension to the XQJ interface) allows a query to be compiled once, and reused concurrently under multiple connections in multiple threads. The compiled code of the existing query and its static context are shared with the original query, but a new dynamic context is established, so that the two expressions can safely be used in parallel.
        Parameters:
        expression - the XQPreparedExpression to be copied. This must have been created using Saxon, and it must have been created with an XQConnection derived from the same XQDataSource as this connection.
        Returns:
        a copy of the supplied expression, that can be used in a different connection or thread with its own dynamic context. The new copy of the expression belongs to this connection, and can be used in the same way as an expression created using any of the prepareExpression() methods on this class.
        Throws:
        XQException - for example if either of the connections has been closed

      • rollback

        public void rollback()
              throws XQException
        Description copied from interface: XQConnection
        Undoes all changes made in the current transaction and releases any locks held by the datasource. This method should be used only when auto-commit mode is disabled.
        Specified by:
        rollback in interface XQConnection
        Throws:
        XQException - if the connection is in a closed state or this connection is operating in auto-commit mode

      • setAutoCommit

        public void setAutoCommit​(boolean autoCommit)
                   throws XQException
        Description copied from interface: XQConnection
        Sets the auto-commit attribute to the given state. If a connection is in auto-commit mode, each xquery is executed and committed in an individual transaction. When auto-commit mode is disabled, xqueries are grouped in a transaction that must be ended explicitly by the application calling commit() or rollback().

        By default, new connections are in auto-commit mode.

        If the value of auto-commit is changed in the middle of a transaction, the transaction is committed. If setAutoCommit is called and the auto-commit attribute is not changed from its current value, the request is treated as a no-op.

        Specified by:
        setAutoCommit in interface XQConnection
        Parameters:
        autoCommit - true to enable auto-commit mode; false to disable it
        Throws:
        XQException - if (1) the connection is in a closed state, or (2) auto-commit is turned off but the implementation doesn't support transactions

      • setStaticContext

        public void setStaticContext​(XQStaticContext properties)
                      throws XQException
        Description copied from interface: XQConnection
        Sets the default values for all expression properties. The implementation will read out all expression properties from the specified XQStaticContext and update its private copy.
        Specified by:
        setStaticContext in interface XQConnection
        Parameters:
        properties - XQStaticContext containing values of expression properties
        Throws:
        XQException - if the connection is in a closed state