1 /*

     2  * Copyright (c) 2011, 2012, 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 com.sun.tools.classfile;

    27 

    28 import java.io.IOException;

    29 

    30 /**

    31  * See JVMS 4.7.21

    32  * http://docs.oracle.com/javase/specs/jvms/se7/html/jvms-4.html#jvms-4.7.21

    33  *

    34  *  <p><b>This is NOT part of any supported API.

    35  *  If you write code that depends on this, you do so at your own risk.

    36  *  This code and its internal interfaces are subject to change or

    37  *  deletion without notice.</b>

    38  */

    39 public class BootstrapMethods_attribute extends Attribute {

    40     public final BootstrapMethodSpecifier[] bootstrap_method_specifiers;

    41 

    42     BootstrapMethods_attribute(ClassReader cr, int name_index, int length)

    43             throws IOException, AttributeException {

    44         super(name_index, length);

    45         int bootstrap_method_count = cr.readUnsignedShort();

    46         bootstrap_method_specifiers = new BootstrapMethodSpecifier[bootstrap_method_count];

    47         for (int i = 0; i < bootstrap_method_specifiers.length; i++)

    48             bootstrap_method_specifiers[i] = new BootstrapMethodSpecifier(cr);

    49     }

    50 

    51     public  BootstrapMethods_attribute(int name_index, BootstrapMethodSpecifier[] bootstrap_method_specifiers) {

    52         super(name_index, length(bootstrap_method_specifiers));

    53         this.bootstrap_method_specifiers = bootstrap_method_specifiers;

    54     }

    55 

    56     public static int length(BootstrapMethodSpecifier[] bootstrap_method_specifiers) {

    57         int n = 2;

    58         for (BootstrapMethodSpecifier b : bootstrap_method_specifiers)

    59             n += b.length();

    60         return n;

    61     }

    62 

    63     @Override

    64     public <R, P> R accept(Visitor<R, P> visitor, P p) {

    65         return visitor.visitBootstrapMethods(this, p);

    66     }

    67 

    68     public static class BootstrapMethodSpecifier {

    69         public int bootstrap_method_ref;

    70         public int[] bootstrap_arguments;

    71 

    72         public BootstrapMethodSpecifier(int bootstrap_method_ref, int[] bootstrap_arguments) {

    73             this.bootstrap_method_ref = bootstrap_method_ref;

    74             this.bootstrap_arguments = bootstrap_arguments;

    75         }

    76         BootstrapMethodSpecifier(ClassReader cr) throws IOException {

    77             bootstrap_method_ref = cr.readUnsignedShort();

    78             int method_count = cr.readUnsignedShort();

    79             bootstrap_arguments = new int[method_count];

    80             for (int i = 0; i < bootstrap_arguments.length; i++) {

    81                 bootstrap_arguments[i] = cr.readUnsignedShort();

    82             }

    83         }

    84 

    85         int length() {

    86             // u2 (method_ref) + u2 (argc) + u2 * argc

    87             return 2 + 2 + (bootstrap_arguments.length * 2);

    88         }

    89     }

    90 }