Examples with LocalVariableAttribute javassist.bytecode.LocalVariableAttribute used on opensource projects

Example 1 with LocalVariableAttribute

use of javassist.bytecode.LocalVariableAttribute in project pinpoint by naver.

the class JavaAssistUtils method lookupLocalVariableAttribute.

/**
     * get LocalVariableAttribute
     *
     * @param method
     * @return null if the class is not compiled with debug option
     */
public static LocalVariableAttribute lookupLocalVariableAttribute(CtBehavior method) {
    if (method == null) {
        throw new NullPointerException("method must not be null");
    }
    MethodInfo methodInfo = method.getMethodInfo2();
    CodeAttribute codeAttribute = methodInfo.getCodeAttribute();
    if (codeAttribute == null) {
        return null;
    }
    AttributeInfo localVariableTable = codeAttribute.getAttribute(LocalVariableAttribute.tag);
    LocalVariableAttribute local = (LocalVariableAttribute) localVariableTable;
    return local;
}

Example 2 with LocalVariableAttribute

use of javassist.bytecode.LocalVariableAttribute in project latke by b3log.

the class Reflections method getMethodVariableNames.

/**
 * getMethodVariableNames in user defined.
 *
 * @param clazz            the specific clazz
 * @param targetMethodName the targetMethodName
 * @param types            the types of the method parameters
 * @return the String[] of names
 */
public static String[] getMethodVariableNames(final Class<?> clazz, final String targetMethodName, final Class<?>[] types) {
    CtClass cc;
    CtMethod cm = null;
    try {
        if (null == CLASS_POOL.find(clazz.getName())) {
            CLASS_POOL.insertClassPath(new ClassClassPath(clazz));
        }
        cc = CLASS_POOL.get(clazz.getName());
        final CtClass[] ptypes = new CtClass[types.length];
        for (int i = 0; i < ptypes.length; i++) {
            ptypes[i] = CLASS_POOL.get(types[i].getName());
        }
        cm = cc.getDeclaredMethod(targetMethodName, ptypes);
    } catch (final NotFoundException e) {
        LOGGER.log(Level.ERROR, "Get method variable names failed", e);
    }
    if (null == cm) {
        return new String[types.length];
    }
    final MethodInfo methodInfo = cm.getMethodInfo();
    final CodeAttribute codeAttribute = methodInfo.getCodeAttribute();
    final LocalVariableAttribute attr = (LocalVariableAttribute) codeAttribute.getAttribute(LocalVariableAttribute.tag);
    String[] variableNames = new String[0];
    try {
        variableNames = new String[cm.getParameterTypes().length];
    } catch (final NotFoundException e) {
        LOGGER.log(Level.ERROR, "Get method variable names failed", e);
    }
    // final int staticIndex = Modifier.isStatic(cm.getModifiers()) ? 0 : 1;
    int j = -1;
    String variableName = null;
    Boolean ifkill = false;
    while (!"this".equals(variableName)) {
        j++;
        variableName = attr.variableName(j);
        // to prevent heap error when there being some unknown reasons to resolve the VariableNames
        if (j > MAX_FIND_LENGTH) {
            LOGGER.log(Level.WARN, "Maybe resolve to VariableNames error [class=" + clazz.getName() + ", targetMethodName=" + targetMethodName + ']');
            ifkill = true;
            break;
        }
    }
    if (!ifkill) {
        for (int i = 0; i < variableNames.length; i++) {
            variableNames[i] = attr.variableName(++j);
        }
    }
    return variableNames;
}

Example 3 with LocalVariableAttribute

use of javassist.bytecode.LocalVariableAttribute in project reflections by ronmamo.

the class MethodParameterNamesScanner method getString.

private String getString(MethodInfo method) {
    CodeAttribute codeAttribute = method.getCodeAttribute();
    LocalVariableAttribute table = codeAttribute != null ? (LocalVariableAttribute) codeAttribute.getAttribute(LocalVariableAttribute.tag) : null;
    int length = JavassistHelper.getParameters(method).size();
    if (length > 0) {
        // skip this
        int shift = Modifier.isStatic(method.getAccessFlags()) ? 0 : 1;
        return IntStream.range(shift, length + shift).mapToObj(i -> method.getConstPool().getUtf8Info(table.nameIndex(i))).filter(name -> !name.startsWith("this$")).collect(Collectors.joining(", "));
    }
    return "";
}

Example 4 with LocalVariableAttribute

use of javassist.bytecode.LocalVariableAttribute in project dubbo-faker by moyada.

the class VariableUtil method getNameByJavassist.

// /**
// * 通过 ASM 获取属性名
// * @param clazz
// * @param method
// * @return
// * @throws IOException
// */
// public static String[] getNameByASM(Class clazz, Method method) throws IOException {
// final Class<?>[] methodParameterTypes = method.getParameterTypes();
// final int methodParameterCount = methodParameterTypes.length;
// final boolean isStatic = Modifier.isStatic(method.getModifiers());
// 
// // 读取字节码信息到ClassReader中
// ClassReader reader = new ClassReader(clazz.getName());
// ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS);
// 
// String[] variableName = new String[methodParameterCount];
// 
// reader.accept(new ClassVisitor(cw.hashCode(), cw) {
// /**
// * 会遍历该类的所有方法，你可以对不需要操作的方法直接返回
// */
// @Override
// public MethodVisitor visitMethod(final int access, final String name, final String desc,
// final String signature, final String[] exceptions) {
// 
// MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions);
// 
// final Type[] argTypes = Type.getArgumentTypes(desc);
// 
// //不需要操作的方法，直接返回，注意不要返回null,会把该方法删掉
// if (!name.equals(method.getName()) || !matchTypes(argTypes, methodParameterTypes)) {
// return mv;
// }
// 
// // 遍历该方法信息
// return new MethodVisitor(mv.hashCode(), mv) {
// 
// @Override
// public void visitLocalVariable(String name, String desc, String signature, Label start, Label end, int index) {
// //如果是静态方法，第一个参数就是方法参数，非静态方法，则第一个参数是 this ,然后才是方法的参数
// int methodParameterIndex = isStatic ? index : index - 1;
// if (0 <= methodParameterIndex && methodParameterIndex < methodParameterCount) {
// variableName[methodParameterIndex] = name;
// }
// super.visitLocalVariable(name, desc, signature, start, end, index);
// }
// };
// }
// }, 0);
// 
// return variableName;
// }
// 
// /**
// * 比较参数是否一致
// */
// private static boolean matchTypes(Type[] types, Class<?>[] parameterTypes) {
// if (types.length != parameterTypes.length) {
// return false;
// }
// for (int i = 0; i < types.length; i++) {
// if (!Type.getType(parameterTypes[i]).equals(types[i])) {
// return false;
// }
// }
// return true;
// }
/**
 * 通过 javassist 获取属性名
 * @param clazz
 * @param method
 * @return
 * @throws NotFoundException
 */
public static String[] getNameByJavassist(Class clazz, Method method) throws NotFoundException {
    ClassPool classPool = ClassPool.getDefault();
    CtClass ctClass = classPool.get(clazz.getName());
    int count = method.getParameterCount();
    Class<?>[] paramTypes = method.getParameterTypes();
    CtClass[] ctParams = new CtClass[count];
    for (int i = 0; i < count; i++) {
        ctParams[i] = classPool.getCtClass(paramTypes[i].getName());
    }
    CtMethod ctMethod = ctClass.getDeclaredMethod(method.getName(), ctParams);
    // 得到该方法信息类
    MethodInfo methodInfo = ctMethod.getMethodInfo();
    // 获取属性变量相关
    CodeAttribute codeAttribute = methodInfo.getCodeAttribute();
    if (codeAttribute == null) {
        return null;
    }
    // 获取方法本地变量信息，包括方法声明和方法体内的变量
    // 需注意，若方法为非静态方法，则第一个变量名为this
    LocalVariableAttribute attr = (LocalVariableAttribute) codeAttribute.getAttribute(LocalVariableAttribute.tag);
    String[] variableName = new String[count];
    int index = 0;
    int pos = 0;
    if (!Modifier.isStatic(method.getModifiers())) {
        count++;
        pos++;
    }
    for (int i = pos; i < count; i++) {
        variableName[index++] = attr.variableName(i);
    }
    return variableName;
}

Example 5 with LocalVariableAttribute

use of javassist.bytecode.LocalVariableAttribute in project leopard by tanhaichao.

the class CtClassUtil method getParameterNames.

/**
 * 获取方法的参数名称.
 *
 * @param ctMethod
 * @return
 * @throws NotFoundException
 */
public static String[] getParameterNames(CtMethod ctMethod) throws NotFoundException {
    MethodInfo methodInfo = ctMethod.getMethodInfo();
    CodeAttribute codeAttribute = methodInfo.getCodeAttribute();
    // logger.info("methodInfo.getConstPool().getSize():");
    LocalVariableAttribute attribute = (LocalVariableAttribute) codeAttribute.getAttribute(LocalVariableAttribute.tag);
    // String[] names = new String[attribute.tableLength() - 1];
    String[] paramNames = new String[ctMethod.getParameterTypes().length];
    int pos = 0;
    if (true) {
        int size = attribute.tableLength();
        if (size > 0) {
            String[] names = new String[size - 1];
            for (int i = 0; i < names.length; i++) {
                names[i] = attribute.variableName(i);
                if ("this".equals(names[i])) {
                    pos = i + 1;
                    break;
                }
            }
        // logger.info(methodInfo.getName() + " pos:" + pos + " allNames:" + StringUtils.join(names, ", "));
        }
    }
    // logger.info(methodInfo.getName() + " pos:" + pos);
    for (int i = 0; i < paramNames.length; i++) {
        // paramNames[i] = attribute.variableName(i + 1);
        try {
            paramNames[i] = attribute.variableName(i + pos);
        // logger.info("paramNames[" + i + "]:" + paramNames[i]);
        } catch (RuntimeException e) {
            throw e;
        }
    }
    // System.err.println("paramNames:" + StringUtils.join(paramNames));
    return paramNames;
}