https://github.com/javaee/jpa-spec: Java(TM) Persistence API 
Copyright (c) 2008 - 2013 Oracle Corporation. All rights reserved.
This program and the accompanying materials are made available under the
terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
which accompanies this distribution.
The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
and the Eclipse Distribution License is available at
http://www.eclipse.org/org/documents/edl-v10.php.
Contributors:
    Linda DeMichiel - Java Persistence 2.1
    Linda DeMichiel - Java Persistence 2.0

/*******************************************************************************
 * Copyright (c) 2008 - 2013 Oracle Corporation. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
 * which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Linda DeMichiel - Java Persistence 2.1
 *     Linda DeMichiel - Java Persistence 2.0
 *
 ******************************************************************************/ 
package javax.persistence;


Type for query parameter objects.

Type parameters:
  • <T> – the type of the parameter
See Also:
Since:Java Persistence 2.0
/**
 * Type for query parameter objects.
 * @param <T> the type of the parameter
 *
 * @see Query
 * @see TypedQuery
 *
 * @since Java Persistence 2.0
 */
public interface Parameter<T> {

    
Return the parameter name, or null if the parameter is
not a named parameter or no name has been assigned.

Returns:parameter name
/**
     * Return the parameter name, or null if the parameter is
     * not a named parameter or no name has been assigned.
     * @return parameter name
     */
    String getName();

    
Return the parameter position, or null if the parameter
is not a positional parameter. 

Returns:position of parameter
/**
     * Return the parameter position, or null if the parameter
     * is not a positional parameter. 
     * @return position of parameter
     */
    Integer getPosition();

    
Return the Java type of the parameter. Values bound to the
parameter must be assignable to this type.
This method is required to be supported for criteria queries
only.   Applications that use this method for Java 
Persistence query language queries and native queries will 
not be portable.

Throws:
  • IllegalStateException – if invoked on a parameter
        obtained from a Java persistence query language 
        query or native query when the implementation does 
        not support this use
Returns:the Java type of the parameter
/**
     * Return the Java type of the parameter. Values bound to the
     * parameter must be assignable to this type.
     * This method is required to be supported for criteria queries
     * only.   Applications that use this method for Java 
     * Persistence query language queries and native queries will 
     * not be portable.
     * @return the Java type of the parameter
     * @throws IllegalStateException if invoked on a parameter
     *         obtained from a Java persistence query language 
     *         query or native query when the implementation does 
     *         not support this use
     */
     Class<T> getParameterType();
}