1 /*

     2  * Copyright (c)  2017, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 package jdk.incubator.sql2;

    27 

    28 import java.lang.annotation.Target;

    29 import static java.lang.annotation.ElementType.CONSTRUCTOR;

    30 import static java.lang.annotation.ElementType.METHOD;

    31 import java.lang.annotation.Retention;

    32 import static java.lang.annotation.RetentionPolicy.RUNTIME;

    33 

    34 

    35 /**

    36  * Identifies a constructor or static factory method that can be used to construct

    37  * an instance of the containing type when the type is passed to {@link Result.ResultMap#get}.

    38  * The method or constructor must be public.

    39  * 

    40  * An instance of this type will be constructed by calling the factory method or

    41  * constructor. Each element in the value of this annotation is used as a column

    42  * identifier. The value of that column is passed to the corresponding parameter

    43  * of the annotated method or constructor. The id argument to {@link Result.ResultMap#get} is 

    44  * prefixed to the column identifiers.

    45  * 

    46  * The following pseudo-code describes how an instance is constructed.

    47  * 

    48  * {@code

    49  * <pre>    int i = 0;

    50  *   String[] columns = methodOrConstructor.getAnnotation(SqlColumns.class).value();

    51  *   Object[] args = new Object[columns.length];

    52  *   for (String columnName : columns)

    53  *     args[i] = resultMap.get(prefix + columnName, parameterTypes[i++];

    54  *   instance = methodOrConstructor.invoke(null, args);</pre>}

    55  * 

    56  */

    57 @Retention(RUNTIME)

    58 @Target({CONSTRUCTOR, METHOD})

    59 public @interface SqlColumns {

    60   

    61   /**

    62    * The column names corresponding to the parameters of the factory method or

    63    * constructor to construct an instance of this type. There must be exactly one 

    64    * column name for each parameter of the annotated method or constructor.

    65    * 

    66    * @return the column names in the order returned by the database

    67    */

    68   public String[] value();

    69 }