/* * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. * * Copyright 1997-2010 Oracle and/or its affiliates. All rights reserved. * * Oracle and Java are registered trademarks of Oracle and/or its affiliates. * Other names may be trademarks of their respective owners. * * The contents of this file are subject to the terms of either the GNU * General Public License Version 2 only ("GPL") or the Common * Development and Distribution License("CDDL") (collectively, the * "License"). You may not use this file except in compliance with the * License. You can obtain a copy of the License at * http://www.netbeans.org/cddl-gplv2.html * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the * specific language governing permissions and limitations under the * License. When distributing the software, include this License Header * Notice in each file and include the License file at * nbbuild/licenses/CDDL-GPL-2-CP. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the GPL Version 2 section of the License file that * accompanied this code. If applicable, add the following below the * License Header, with the fields enclosed by brackets [] replaced by * your own identifying information: * "Portions Copyrighted [year] [name of copyright owner]" * * Contributor(s): * * The Original Software is NetBeans. The Initial Developer of the Original * Software is Sun Microsystems, Inc. Portions Copyright 1997-2006 Sun * Microsystems, Inc. All Rights Reserved. * * If you wish your version of this file to be governed by only the CDDL * or only the GPL Version 2, indicate your decision by adding * "[Contributor] elects to include this software in this distribution * under the [CDDL or GPL Version 2] license." If you do not indicate a * single choice of license, a recipient has the option to distribute * your version of this file under either the CDDL, the GPL Version 2 or * to extend the choice of license to its licensees as provided above. * However, if you add GPL Version 2 code and therefore, elected the GPL * Version 2 license, then the option applies only if the new code is * made subject to such option by the copyright holder. */ package org.netbeans; import java.io.UnsupportedEncodingException; import org.openide.modules.PatchedPublic; /** * Tool to patch bytecode, currently just to make access modifiers public. * Determines when and what to patch based on class-retention annotations. * @see PatchedPublic * @see #patch */ public final class PatchByteCode { private static final byte[] RUNTIME_INVISIBLE_ANNOTATIONS, PATCHED_PUBLIC; static { try { RUNTIME_INVISIBLE_ANNOTATIONS = "RuntimeInvisibleAnnotations".getBytes("UTF-8"); // NOI18N PATCHED_PUBLIC = ("L" + PatchedPublic.class.getName().replace('.', '/') + ";").getBytes("UTF-8"); // NOI18N } catch (UnsupportedEncodingException x) { throw new ExceptionInInitializerError(x); } } /** * Patches a class if it is needed. * @param arr the bytecode * @return the enhanced bytecode */ public static byte[] patch(byte[] data) { int constant_pool_count = u2(data, /* magic + minor_version + major_version */ 8); int[] constantPoolOffsets = new int[constant_pool_count]; int pos = 10; // 8 + constant_pool_count for (int i = 1; i < constant_pool_count; i++) { int tag = u1(data, pos++); //System.err.println("tag " + tag + " at #" + i + " at location " + pos); constantPoolOffsets[i] = pos; switch (tag) { case 1: // CONSTANT_Utf8 int len = u2(data, pos); //try {System.err.println("UTF-8 constant: " + new String(data, pos + 2, len, "UTF-8"));} catch (UnsupportedEncodingException x) {} pos += len + 2; break; case 3: // CONSTANT_Integer case 4: // CONSTANT_Float case 9: // CONSTANT_Fieldref case 10: // CONSTANT_Methodref case 11: // CONSTANT_InterfaceMethodref case 12: // CONSTANT_NameAndType pos += 4; break; case 7: // CONSTANT_Class case 8: // CONSTANT_String pos += 2; break; case 5: // CONSTANT_Long case 6: // CONSTANT_Double pos += 8; i++; // next entry is ignored break; default: throw new IllegalArgumentException("illegal constant pool tag " + tag + " at index " + i + " out of " + constant_pool_count); } } pos += 6; // access_flags + this_class + super_class int interfaces_count = u2(data, pos); pos += 2; // interfaces_count pos += 2 * interfaces_count; // interfaces int fields_count = u2(data, pos); pos += 2; // fields_count for (int i = 0; i < fields_count; i++) { pos += 6; // access_flags + name_index + descriptor_index int attributes_count = u2(data, pos); pos += 2; // attributes_count for (int j = 0; j < attributes_count; j++) { pos += 2; // attribute_name_index int attribute_length = u4(data, pos); pos += 4; // attribute_length pos += attribute_length; // info } } int methods_count = u2(data, pos); pos += 2; // methods_count for (int i = 0; i < methods_count; i++) { int locationOfAccessFlags = pos; pos += 6; // access_flags + name_index + descriptor_index int attributes_count = u2(data, pos); pos += 2; // attributes_count for (int j = 0; j < attributes_count; j++) { int locationOfAttributeName = constantPoolOffsets[u2(data, pos)]; pos += 2; // attribute_name_index int attribute_length = u4(data, pos); pos += 4; // attribute_length if (utf8Matches(data, locationOfAttributeName, RUNTIME_INVISIBLE_ANNOTATIONS)) { int num_annotations = u2(data, pos); int pos2 = pos + 2; // num_annotations for (int k = 0; k < num_annotations; k++) { if (utf8Matches(data, constantPoolOffsets[u2(data, pos2)], PATCHED_PUBLIC)) { // Got it, we are setting the method to be public. data[locationOfAccessFlags + 1] &= 0xF9; // - ACC_PRIVATE - ACC_PROTECTED data[locationOfAccessFlags + 1] |= 0x01; // + ACC_PUBLIC } // XXX skip over annotation body so we can support >1 annotation on the member // (i.e. @PatchedPublic occurs only after other annotations) // but it is tedious to calculate the length of element_value structs continue; } } pos += attribute_length; // info } } return data; } private static int u1(byte[] data, int off) { byte b = data[off]; return b >= 0 ? b : b + 256; } private static int u2(byte[] data, int off) { return (u1(data, off) << 8) + u1(data, off + 1); } private static int u4(byte[] data, int off) { return (u2(data, off) << 16) + u2(data, off + 2); } private static boolean utf8Matches(byte[] data, int off, byte[] expected) { if (u2(data, off) != expected.length) { return false; } for (int i = 0; i < expected.length; i++) { if (data[off + 2 + i] != expected[i]) { return false; } } return true; } }