| // ASM: a very small and fast Java bytecode manipulation framework |
| // Copyright (c) 2000-2011 INRIA, France Telecom |
| // All rights reserved. |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions |
| // are met: |
| // 1. Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // 2. Redistributions in binary form must reproduce the above copyright |
| // notice, this list of conditions and the following disclaimer in the |
| // documentation and/or other materials provided with the distribution. |
| // 3. Neither the name of the copyright holders nor the names of its |
| // contributors may be used to endorse or promote products derived from |
| // this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF |
| // THE POSSIBILITY OF SUCH DAMAGE. |
| package org.apache.tapestry5.internal.plastic.asm.commons; |
| |
| import org.apache.tapestry5.internal.plastic.asm.ClassVisitor; |
| import org.apache.tapestry5.internal.plastic.asm.MethodVisitor; |
| import org.apache.tapestry5.internal.plastic.asm.Opcodes; |
| |
| /** |
| * A {@link ClassVisitor} that merges <clinit> methods into a single one. All the existing |
| * <clinit> methods are renamed, and a new one is created, which calls all the renamed |
| * methods. |
| * |
| * @author Eric Bruneton |
| */ |
| public class StaticInitMerger extends ClassVisitor { |
| |
| /** The internal name of the visited class. */ |
| private String owner; |
| |
| /** The prefix to use to rename the existing <clinit> methods. */ |
| private final String renamedClinitMethodPrefix; |
| |
| /** The number of <clinit> methods visited so far. */ |
| private int numClinitMethods; |
| |
| /** The MethodVisitor for the merged <clinit> method. */ |
| private MethodVisitor mergedClinitVisitor; |
| |
| /** |
| * Constructs a new {@link StaticInitMerger}. <i>Subclasses must not use this constructor</i>. |
| * Instead, they must use the {@link #StaticInitMerger(int, String, ClassVisitor)} version. |
| * |
| * @param prefix the prefix to use to rename the existing <clinit> methods. |
| * @param classVisitor the class visitor to which this visitor must delegate method calls. May be |
| * null. |
| */ |
| public StaticInitMerger(final String prefix, final ClassVisitor classVisitor) { |
| this(/* latest api = */ Opcodes.ASM8, prefix, classVisitor); |
| } |
| |
| /** |
| * Constructs a new {@link StaticInitMerger}. |
| * |
| * @param api the ASM API version implemented by this visitor. Must be one of {@link |
| * Opcodes#ASM4}, {@link Opcodes#ASM5}, {@link Opcodes#ASM6}, {@link Opcodes#ASM7} or {@link |
| * Opcodes#ASM8}. |
| * @param prefix the prefix to use to rename the existing <clinit> methods. |
| * @param classVisitor the class visitor to which this visitor must delegate method calls. May be |
| * null. |
| */ |
| protected StaticInitMerger(final int api, final String prefix, final ClassVisitor classVisitor) { |
| super(api, classVisitor); |
| this.renamedClinitMethodPrefix = prefix; |
| } |
| |
| @Override |
| public void visit( |
| final int version, |
| final int access, |
| final String name, |
| final String signature, |
| final String superName, |
| final String[] interfaces) { |
| super.visit(version, access, name, signature, superName, interfaces); |
| this.owner = name; |
| } |
| |
| @Override |
| public MethodVisitor visitMethod( |
| final int access, |
| final String name, |
| final String descriptor, |
| final String signature, |
| final String[] exceptions) { |
| MethodVisitor methodVisitor; |
| if ("<clinit>".equals(name)) { |
| int newAccess = Opcodes.ACC_PRIVATE + Opcodes.ACC_STATIC; |
| String newName = renamedClinitMethodPrefix + numClinitMethods++; |
| methodVisitor = super.visitMethod(newAccess, newName, descriptor, signature, exceptions); |
| |
| if (mergedClinitVisitor == null) { |
| mergedClinitVisitor = super.visitMethod(newAccess, name, descriptor, null, null); |
| } |
| mergedClinitVisitor.visitMethodInsn(Opcodes.INVOKESTATIC, owner, newName, descriptor, false); |
| } else { |
| methodVisitor = super.visitMethod(access, name, descriptor, signature, exceptions); |
| } |
| return methodVisitor; |
| } |
| |
| @Override |
| public void visitEnd() { |
| if (mergedClinitVisitor != null) { |
| mergedClinitVisitor.visitInsn(Opcodes.RETURN); |
| mergedClinitVisitor.visitMaxs(0, 0); |
| } |
| super.visitEnd(); |
| } |
| } |