Example usage for org.objectweb.asm ClassVisitor ClassVisitor

List of usage examples for org.objectweb.asm ClassVisitor ClassVisitor

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Introduction

In this page you can find the example usage for org.objectweb.asm ClassVisitor ClassVisitor.

Prototype

public ClassVisitor(final int api, final ClassVisitor classVisitor)

Source Link

Document

Constructs a new ClassVisitor .

Usage

From source file:co.cask.cdap.internal.app.runtime.adapter.PluginTest.java

License:Apache License

private static File generateClass(Class<?> fromClass, final String className, File directory)
        throws IOException {
    // Generate a class dynamically using ASM from another class, but use a different class name,
    // so that it won't be in the test class path.
    try (InputStream byteCode = fromClass.getClassLoader()
            .getResourceAsStream(Type.getInternalName(fromClass) + ".class")) {
        ClassReader reader = new ClassReader(byteCode);
        ClassWriter writer = new ClassWriter(0);
        reader.accept(new ClassVisitor(Opcodes.ASM5, writer) {
            @Override/*from w  w  w .  ja v a 2 s.co  m*/
            public void visit(int version, int access, String name, String signature, String superName,
                    String[] interfaces) {
                super.visit(version, access, className.replace('.', '/'), signature, superName, interfaces);
            }
        }, 0);

        File target = new File(directory, className.replace('.', File.separatorChar) + ".class");
        DirUtils.mkdirs(target.getParentFile());
        Files.write(writer.toByteArray(), target);
        return target;
    }
}

From source file:co.cask.cdap.internal.app.runtime.batch.distributed.MapReduceContainerHelper.java

License:Apache License

/**
 * Rewrites the TwillLauncher bytecode as described
 * in {@link #saveLauncher(Configuration, File, List)}.
 *
 * @param hConf the hadoop configuration
 * @param sourceByteCode the original bytecode of the TwillLauncher
 * @param output output stream for writing the modified bytecode.
 * @throws IOException//from   w w w. java 2  s  . c  om
 */
private static void rewriteLauncher(Configuration hConf, InputStream sourceByteCode, OutputStream output)
        throws IOException {
    URI frameworkURI = getFrameworkURI(hConf);
    if (frameworkURI == null) {
        ByteStreams.copy(sourceByteCode, output);
        return;
    }

    // It is localized as archive, and due to TWILL-144, a suffix is added. We need to reverse the effect of it
    // by creating an extra symlink as the first line in the TwillLauncher.main() method.
    String ext = Paths.getExtension(frameworkURI.getPath());
    if (ext.isEmpty()) {
        ByteStreams.copy(sourceByteCode, output);
        return;
    }

    final String sourceName = frameworkURI.getFragment();
    final String targetName = sourceName + "." + ext;

    ClassReader cr = new ClassReader(sourceByteCode);
    ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS);
    cr.accept(new ClassVisitor(Opcodes.ASM5, cw) {

        @Override
        public MethodVisitor visitMethod(int access, String name, String desc, String signature,
                String[] exceptions) {
            MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions);
            if (!name.equals("main")) {
                return mv;
            }
            Type[] argTypes = Type.getArgumentTypes(desc);
            if (argTypes.length != 1) {
                return mv;
            }
            Type argType = argTypes[0];
            if (argType.getSort() != Type.ARRAY
                    || !String.class.getName().equals(argType.getElementType().getClassName())) {
                return mv;
            }

            return new AdviceAdapter(Opcodes.ASM5, mv, access, name, desc) {
                @Override
                protected void onMethodEnter() {
                    visitLdcInsn(sourceName);
                    visitLdcInsn(targetName);
                    invokeStatic(Type.getType(MapReduceContainerSymLinker.class),
                            Methods.getMethod(void.class, "symlink", String.class, String.class));
                }
            };
        }
    }, ClassReader.EXPAND_FRAMES);

    output.write(cw.toByteArray());
}

From source file:co.paralleluniverse.fibers.instrument.JavaAgent.java

License:Open Source License

public static byte[] crazyClojureOnceDisable(ClassLoader loader, String className, Class<?> classBeingRedefined,
        ProtectionDomain protectionDomain, byte[] classfileBuffer) throws IllegalClassFormatException {
    if (!Boolean.parseBoolean(System.getProperty("co.paralleluniverse.pulsar.disableOnce", "false")))
        return classfileBuffer;

    ClassReader cr = new ClassReader(classfileBuffer);
    ClassWriter cw = new ClassWriter(cr, 0);
    ClassVisitor cv = new ClassVisitor(Opcodes.ASM4, cw) {

        @Override/*from  ww w  . j  a  v  a  2  s.  c om*/
        public MethodVisitor visitMethod(int access, String name, String desc, String signature,
                String[] exceptions) {
            return new MethodVisitor(api, super.visitMethod(access, name, desc, signature, exceptions)) {

                @Override
                public void visitLdcInsn(Object cst) {
                    if (cst instanceof String && cst.equals("once")) {
                        super.visitLdcInsn("once$disabled-by-pulsar");
                    } else
                        super.visitLdcInsn(cst);
                }

            };
        }
    };
    cr.accept(cv, 0);
    return cw.toByteArray();
}

From source file:co.paralleluniverse.fibers.instrument.ModuleFilterTask.java

License:Open Source License

private void filter(File file) {
    try {//from w w w . j a  va 2s .  co  m
        ClassWriter cw = null;
        try (FileInputStream fis = new FileInputStream(file)) {
            ClassReader cr = new ClassReader(fis);
            cw = new ClassWriter(cr, 0);
            cr.accept(new ClassVisitor(Opcodes.ASM7, cw) {
                @Override
                public ModuleVisitor visitModule(String name, int access, String version) {
                    return new ModuleVisitor(Opcodes.ASM7, super.visitModule(name, access, version)) {
                        @Override
                        public void visitRequire(String module, int access, String version) {
                            if (!module.contains(mod)) {
                                super.visitRequire(module, access, version);
                            }
                        }
                    };
                }
            }, 0);
        }

        try (FileOutputStream fos = new FileOutputStream(file)) {
            fos.write(cw.toByteArray());
        }
    } catch (IOException ex) {
        throw new BuildException("Filterin module-info file " + file, ex);
    }
}

From source file:co.paralleluniverse.vtime.VirtualTimeClassTransformer.java

License:Open Source License

private ClassVisitor createVisitor(ClassVisitor next) {
    int api;//from w  ww  . j  a  va  2s.  c  om
    if (System.getProperty("java.version").startsWith("1.8")) {
        api = Opcodes.ASM5;
    } else if (System.getProperty("java.version").startsWith("10")) {
        api = Opcodes.ASM6;
    } else {
        api = Opcodes.ASM7;
    }
    return new ClassVisitor(api, next) {
        @Override
        public MethodVisitor visitMethod(int access, String name, String desc, String signature,
                String[] exceptions) {
            return new MethodVisitor(api, super.visitMethod(access, name, desc, signature, exceptions)) {
                @Override
                public void visitMethodInsn(int opcode, String owner, String name, String desc, boolean itf) {
                    if (!captureTimeCall(owner, name, desc)) {
                        super.visitMethodInsn(opcode, owner, name, desc, itf);
                    }
                }

                private boolean captureTimeCall(String owner, String name, String desc) {
                    switch (owner) {
                    case "java/lang/Object":
                        if ("wait".equals(name)) {
                            return callClockMethod("Object_wait", instanceToStatic(owner, desc));
                        }
                        break;
                    case "java/lang/System":
                        switch (name) {
                        case "nanoTime":
                            return callClockMethod("System_nanoTime", desc);
                        case "currentTimeMillis":
                            return callClockMethod("System_currentTimeMillis", desc);
                        }
                        break;
                    case "java/lang/Thread":
                        if ("sleep".equals(name)) {
                            return callClockMethod("Thread_sleep", desc);
                        }
                        break;
                    case "sun/misc/Unsafe":
                        if ("park".equals(name)) {
                            return callClockMethod("Unsafe_park", instanceToStatic(owner, desc));
                        }
                        break;
                    case "java/lang/management/RuntimeMXBean":
                        if ("getStartTime".equals(name)) {
                            return callClockMethod("RuntimeMXBean_getStartTime", instanceToStatic(owner, desc));
                        }
                        break;
                    }
                    return false;
                }

                private boolean callClockMethod(String name, String desc) {
                    if (includedMethods == null || includedMethods.contains(name)) {
                        super.visitMethodInsn(Opcodes.INVOKESTATIC, CLOCK, name, desc, false);
                        return true;
                    } else {
                        return false;
                    }
                }

                private String instanceToStatic(String owner, String desc) {
                    return "(L" + owner + ";" + desc.substring(1);
                }
            };
        }
    };
}

From source file:com.android.build.gradle.integration.application.ExternalBuildPluginTest.java

License:Apache License

private static byte[] hotswapChange(byte[] inputClass) {
    ClassReader cr = new ClassReader(inputClass);
    ClassWriter cw = new ClassWriter(cr, ClassWriter.COMPUTE_FRAMES);
    ClassVisitor cv = new ClassVisitor(Opcodes.ASM5, cw) {
        @Override//from  ww w  . ja  va  2  s  . c  om
        public MethodVisitor visitMethod(int access, String name, String desc, String signature,
                String[] exceptions) {
            MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions);
            return new MethodVisitor(Opcodes.ASM5, mv) {
                @Override
                public void visitCode() {
                    // add a useless logging to the method.
                    mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;");
                    mv.visitLdcInsn("test changed !");
                    mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/io/PrintStream", "println",
                            "(Ljava/lang/String;)V", false);
                    super.visitCode();
                }
            };
        }
    };
    cr.accept(cv, ClassReader.EXPAND_FRAMES);
    return cw.toByteArray();
}

From source file:com.android.build.gradle.tasks.annotations.TypedefRemover.java

License:Apache License

/**
 * Rewrites the outer classes containing the typedefs such that they no longer refer to
 * the (now removed) typedef annotation inner classes
 *//*from w ww.  j a va  2s. c  om*/
private void rewriteOuterClasses() {
    for (File file : mAnnotationOuterClassFiles) {
        byte[] bytes;
        try {
            bytes = Files.toByteArray(file);
        } catch (IOException e) {
            Extractor.error("Could not read " + file + ": " + e.getLocalizedMessage());
            continue;
        }

        ClassWriter classWriter = new ClassWriter(ASM5);
        ClassVisitor classVisitor = new ClassVisitor(ASM5, classWriter) {
            @Override
            public void visitInnerClass(String name, String outerName, String innerName, int access) {
                if (!mAnnotationNames.contains(name)) {
                    super.visitInnerClass(name, outerName, innerName, access);
                }
            }
        };
        ClassReader reader = new ClassReader(bytes);
        reader.accept(classVisitor, 0);
        byte[] rewritten = classWriter.toByteArray();
        try {
            Files.write(rewritten, file);
        } catch (IOException e) {
            Extractor.error("Could not write " + file + ": " + e.getLocalizedMessage());
            //noinspection UnnecessaryContinue
            continue;
        }
    }
}

From source file:com.android.ide.eclipse.adt.internal.resources.manager.ProjectClassLoader.java

License:Open Source License

/**
 * Rewrites the given class to the given target class file version.
 *//*from w w  w  .j  a v a  2  s.c om*/
public static byte[] rewriteClass(byte[] classData, final int maxVersion, final int minVersion) {
    assert maxVersion >= minVersion;
    ClassWriter classWriter = new ClassWriter(0);
    ClassVisitor classVisitor = new ClassVisitor(Opcodes.ASM5, classWriter) {
        @Override
        public void visit(int version, int access, String name, String signature, String superName,
                String[] interfaces) {
            if (version > maxVersion) {
                version = maxVersion;
            }
            if (version < minVersion) {
                version = minVersion;
            }
            super.visit(version, access, name, signature, superName, interfaces);
        }
    };
    ClassReader reader = new ClassReader(classData);
    reader.accept(classVisitor, 0);
    return classWriter.toByteArray();
}

From source file:com.android.tools.lint.psi.extract.ExtractPsi.java

License:Apache License

public byte[] computeClass(final CgClass clazz) throws IOException {
    assert clazz.isReachable();
    ClassWriter classWriter = new ClassWriter(ASM5);
    ClassVisitor classVisitor = new ClassVisitor(ASM5, classWriter) {
        @Override/*from www  .  j  a va 2 s . co m*/
        public void visitInnerClass(String name, String outerName, String innerName, int access) {
            CgClass clz = findClass(name);
            if (clz != null && clz.isReachable()) {
                super.visitInnerClass(name, outerName, innerName, access);
            }
        }

        @Override
        public void visit(int version, int access, String name, String signature, String superName,
                String[] interfaces) {
            // TODO: Filter out interfaces if they're not used?
            super.visit(version, access, name, signature, superName, interfaces);
        }

        @Override
        public MethodVisitor visitMethod(int access, String name, String desc, String signature,
                String[] exceptions) {
            // Special cases: strip out method bodies for
            //   (1) PsiElementVisitor#visitElement(PsiElement element) -
            //       its current implementation is just
            //       ProgressIndicatorProvider.checkCanceled();
            //       which we *don't* want (service lookup for that provider etc)
            //   (2) Remove the constructor body of PsiDisjunctionType; remove the
            //       myManager field, and the newDisjunctionType(final List<PsiType> types)
            //       method. These don't work outside of

            // TODO: What about inner classes? Here the class name won't be right!
            CgMethod method = findMethod(clazz.getName(), name, desc);
            if (method != null && method.isReachable()) {
                if (method.toString().equals(
                        "com/intellij/psi/PsiDisjunctionType#<init>(Ljava/util/List;Lcom/intellij/psi/PsiManager;)V")) {
                    // Strip off the PsiManager parameter. The method body referencing it
                    // has already been wiped out.
                    desc = "(Ljava/util/List;)V";
                    signature = "(Ljava/util/List<Lcom/intellij/psi/PsiType;>;)V";
                    method.mMethodNode.invisibleParameterAnnotations = null;
                    ArrayList<Object> parameters = new ArrayList<Object>();
                    parameters.add(method.mMethodNode.localVariables.get(0));
                    parameters.add(method.mMethodNode.localVariables.get(1));
                    method.mMethodNode.localVariables = parameters;
                }

                return super.visitMethod(access, name, desc, signature, exceptions);
            }

            return null;
        }

        @Override
        public FieldVisitor visitField(int access, String name, String desc, String signature, Object value) {
            CgField method = findField(clazz.getName(), name);
            if (method != null && method.isReachable()) {
                return super.visitField(access, name, desc, signature, value);
            }

            return null;
        }
    };
    clazz.mClassNode.accept(classVisitor);
    return classWriter.toByteArray();
}

From source file:com.android.tools.rmtypedefs.RmTypeDefs.java

License:Apache License

/**
 * Rewrites the outer classes containing the typedefs such that they no longer refer to
 * the (now removed) typedef annotation inner classes
 *//* ww  w  .  j a  v  a2 s .  c  om*/
private void rewriteOuterClasses() {
    for (File file : mAnnotationOuterClassFiles) {
        byte[] bytes;
        try {
            bytes = Files.toByteArray(file);
        } catch (IOException e) {
            System.err.println("Could not read " + file + ": " + e.getLocalizedMessage());
            mHaveError = true;
            continue;
        }

        ClassWriter classWriter = new ClassWriter(ASM5);
        ClassVisitor classVisitor = new ClassVisitor(ASM5, classWriter) {
            @Override
            public void visitInnerClass(String name, String outerName, String innerName, int access) {
                if (!mAnnotationNames.contains(name)) {
                    super.visitInnerClass(name, outerName, innerName, access);
                }
            }
        };
        ClassReader reader = new ClassReader(bytes);
        reader.accept(classVisitor, 0);
        byte[] rewritten = classWriter.toByteArray();
        try {
            Files.write(rewritten, file);
        } catch (IOException e) {
            System.err.println("Could not write " + file + ": " + e.getLocalizedMessage());
            mHaveError = true;
            //noinspection UnnecessaryContinue
            continue;
        }
    }
}