dubbo ReflectUtils 源码

  • 2022-10-20
  • 浏览 (428)

dubbo ReflectUtils 代码

文件路径:/dubbo-common/src/main/java/org/apache/dubbo/common/utils/ReflectUtils.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.dubbo.common.utils;

import javassist.CtClass;
import javassist.CtConstructor;
import javassist.CtMethod;
import javassist.NotFoundException;

import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.MethodDescriptor;
import java.lang.reflect.Array;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.GenericArrayType;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import java.net.URL;
import java.security.CodeSource;
import java.security.ProtectionDomain;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Date;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.Set;
import java.util.concurrent.Future;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import java.util.stream.Stream;

import static java.util.Arrays.asList;
import static java.util.Collections.unmodifiableSet;
import static org.apache.dubbo.common.utils.ArrayUtils.isEmpty;

/**
 * ReflectUtils
 */
public final class ReflectUtils {

    /**
     * void(V).
     */
    public static final char JVM_VOID = 'V';

    /**
     * boolean(Z).
     */
    public static final char JVM_BOOLEAN = 'Z';

    /**
     * byte(B).
     */
    public static final char JVM_BYTE = 'B';

    /**
     * char(C).
     */
    public static final char JVM_CHAR = 'C';

    /**
     * double(D).
     */
    public static final char JVM_DOUBLE = 'D';

    /**
     * float(F).
     */
    public static final char JVM_FLOAT = 'F';

    /**
     * int(I).
     */
    public static final char JVM_INT = 'I';

    /**
     * long(J).
     */
    public static final char JVM_LONG = 'J';

    /**
     * short(S).
     */
    public static final char JVM_SHORT = 'S';

    public static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0];

    public static final String JAVA_IDENT_REGEX = "(?:[_$a-zA-Z][_$a-zA-Z0-9]*)";

    public static final String JAVA_NAME_REGEX = "(?:" + JAVA_IDENT_REGEX + "(?:\\." + JAVA_IDENT_REGEX + ")*)";

    public static final String CLASS_DESC = "(?:L" + JAVA_IDENT_REGEX + "(?:\\/" + JAVA_IDENT_REGEX + ")*;)";

    public static final String ARRAY_DESC = "(?:\\[+(?:(?:[VZBCDFIJS])|" + CLASS_DESC + "))";

    public static final String DESC_REGEX = "(?:(?:[VZBCDFIJS])|" + CLASS_DESC + "|" + ARRAY_DESC + ")";

    public static final Pattern DESC_PATTERN = Pattern.compile(DESC_REGEX);

    public static final String METHOD_DESC_REGEX = "(?:(" + JAVA_IDENT_REGEX + ")?\\((" + DESC_REGEX + "*)\\)(" + DESC_REGEX + ")?)";

    public static final Pattern METHOD_DESC_PATTERN = Pattern.compile(METHOD_DESC_REGEX);

    public static final Pattern GETTER_METHOD_DESC_PATTERN = Pattern.compile("get([A-Z][_a-zA-Z0-9]*)\\(\\)(" + DESC_REGEX + ")");

    public static final Pattern SETTER_METHOD_DESC_PATTERN = Pattern.compile("set([A-Z][_a-zA-Z0-9]*)\\((" + DESC_REGEX + ")\\)V");

    public static final Pattern IS_HAS_CAN_METHOD_DESC_PATTERN = Pattern.compile("(?:is|has|can)([A-Z][_a-zA-Z0-9]*)\\(\\)Z");

    private static Map<Class<?>, Object> primitiveDefaults = new HashMap<>();

    static {
        primitiveDefaults.put(int.class, 0);
        primitiveDefaults.put(long.class, 0L);
        primitiveDefaults.put(byte.class, (byte) 0);
        primitiveDefaults.put(char.class, (char) 0);
        primitiveDefaults.put(short.class, (short) 0);
        primitiveDefaults.put(float.class, (float) 0);
        primitiveDefaults.put(double.class, (double) 0);
        primitiveDefaults.put(boolean.class, false);
        primitiveDefaults.put(void.class, null);
    }

    private ReflectUtils() {
    }

    public static boolean isPrimitives(Class<?> cls) {
        while (cls.isArray()) {
            cls = cls.getComponentType();
        }
        return isPrimitive(cls);
    }

    public static boolean isPrimitive(Class<?> cls) {
        return cls.isPrimitive() || cls == String.class || cls == Boolean.class || cls == Character.class
                || Number.class.isAssignableFrom(cls) || Date.class.isAssignableFrom(cls);
    }

    public static Class<?> getBoxedClass(Class<?> c) {
        if (c == int.class) {
            c = Integer.class;
        } else if (c == boolean.class) {
            c = Boolean.class;
        } else if (c == long.class) {
            c = Long.class;
        } else if (c == float.class) {
            c = Float.class;
        } else if (c == double.class) {
            c = Double.class;
        } else if (c == char.class) {
            c = Character.class;
        } else if (c == byte.class) {
            c = Byte.class;
        } else if (c == short.class) {
            c = Short.class;
        }
        return c;
    }

    /**
     * is compatible.
     *
     * @param c class.
     * @param o instance.
     * @return compatible or not.
     */
    public static boolean isCompatible(Class<?> c, Object o) {
        boolean pt = c.isPrimitive();
        if (o == null) {
            return !pt;
        }

        if (pt) {
            c = getBoxedClass(c);
        }

        return c == o.getClass() || c.isInstance(o);
    }

    /**
     * is compatible.
     *
     * @param cs class array.
     * @param os object array.
     * @return compatible or not.
     */
    public static boolean isCompatible(Class<?>[] cs, Object[] os) {
        int len = cs.length;
        if (len != os.length) {
            return false;
        }
        if (len == 0) {
            return true;
        }
        for (int i = 0; i < len; i++) {
            if (!isCompatible(cs[i], os[i])) {
                return false;
            }
        }
        return true;
    }

    public static String getCodeBase(Class<?> cls) {
        if (cls == null) {
            return null;
        }
        ProtectionDomain domain = cls.getProtectionDomain();
        if (domain == null) {
            return null;
        }
        CodeSource source = domain.getCodeSource();
        if (source == null) {
            return null;
        }
        URL location = source.getLocation();
        if (location == null) {
            return null;
        }
        return location.getFile();
    }

    /**
     * get name.
     * java.lang.Object[][].class => "java.lang.Object[][]"
     *
     * @param c class.
     * @return name.
     */
    public static String getName(Class<?> c) {
        if (c.isArray()) {
            StringBuilder sb = new StringBuilder();
            do {
                sb.append("[]");
                c = c.getComponentType();
            }
            while (c.isArray());

            return c.getName() + sb.toString();
        }
        return c.getName();
    }

    public static Class<?> getGenericClass(Class<?> cls) {
        return getGenericClass(cls, 0);
    }

    public static Class<?> getGenericClass(Class<?> cls, int i) {
        try {
            ParameterizedType parameterizedType = ((ParameterizedType) cls.getGenericInterfaces()[0]);
            Object genericClass = parameterizedType.getActualTypeArguments()[i];

            // handle nested generic type
            if (genericClass instanceof ParameterizedType) {
                return (Class<?>) ((ParameterizedType) genericClass).getRawType();
            }

            // handle array generic type
            if (genericClass instanceof GenericArrayType) {
                return (Class<?>) ((GenericArrayType) genericClass).getGenericComponentType();
            }

            // Requires JDK 7 or higher, Foo<int[]> is no longer GenericArrayType
            if (((Class) genericClass).isArray()) {
                return ((Class) genericClass).getComponentType();
            }
            return (Class<?>) genericClass;
        } catch (Throwable e) {
            throw new IllegalArgumentException(cls.getName() + " generic type undefined!", e);
        }
    }

    /**
     * get method name.
     * "void do(int)", "void do()", "int do(java.lang.String,boolean)"
     *
     * @param m method.
     * @return name.
     */
    public static String getName(final Method m) {
        StringBuilder ret = new StringBuilder();
        ret.append(getName(m.getReturnType())).append(' ');
        ret.append(m.getName()).append('(');
        Class<?>[] parameterTypes = m.getParameterTypes();
        for (int i = 0; i < parameterTypes.length; i++) {
            if (i > 0) {
                ret.append(',');
            }
            ret.append(getName(parameterTypes[i]));
        }
        ret.append(')');
        return ret.toString();
    }

    public static String getSignature(String methodName, Class<?>[] parameterTypes) {
        StringBuilder sb = new StringBuilder(methodName);
        sb.append('(');
        if (parameterTypes != null && parameterTypes.length > 0) {
            boolean first = true;
            for (Class<?> type : parameterTypes) {
                if (first) {
                    first = false;
                } else {
                    sb.append(',');
                }
                sb.append(type.getName());
            }
        }
        sb.append(')');
        return sb.toString();
    }

    /**
     * get constructor name.
     * "()", "(java.lang.String,int)"
     *
     * @param c constructor.
     * @return name.
     */
    public static String getName(final Constructor<?> c) {
        StringBuilder ret = new StringBuilder("(");
        Class<?>[] parameterTypes = c.getParameterTypes();
        for (int i = 0; i < parameterTypes.length; i++) {
            if (i > 0) {
                ret.append(',');
            }
            ret.append(getName(parameterTypes[i]));
        }
        ret.append(')');
        return ret.toString();
    }

    /**
     * get class desc.
     * boolean[].class => "[Z"
     * Object.class => "Ljava/lang/Object;"
     *
     * @param c class.
     * @return desc.
     * @throws NotFoundException
     */
    public static String getDesc(Class<?> c) {
        StringBuilder ret = new StringBuilder();

        while (c.isArray()) {
            ret.append('[');
            c = c.getComponentType();
        }

        if (c.isPrimitive()) {
            String t = c.getName();
            if ("void".equals(t)) {
                ret.append(JVM_VOID);
            } else if ("boolean".equals(t)) {
                ret.append(JVM_BOOLEAN);
            } else if ("byte".equals(t)) {
                ret.append(JVM_BYTE);
            } else if ("char".equals(t)) {
                ret.append(JVM_CHAR);
            } else if ("double".equals(t)) {
                ret.append(JVM_DOUBLE);
            } else if ("float".equals(t)) {
                ret.append(JVM_FLOAT);
            } else if ("int".equals(t)) {
                ret.append(JVM_INT);
            } else if ("long".equals(t)) {
                ret.append(JVM_LONG);
            } else if ("short".equals(t)) {
                ret.append(JVM_SHORT);
            }
        } else {
            ret.append('L');
            ret.append(c.getName().replace('.', '/'));
            ret.append(';');
        }
        return ret.toString();
    }

    /**
     * get class array desc.
     * [int.class, boolean[].class, Object.class] => "I[ZLjava/lang/Object;"
     *
     * @param cs class array.
     * @return desc.
     * @throws NotFoundException
     */
    public static String getDesc(final Class<?>[] cs) {
        if (cs.length == 0) {
            return "";
        }

        StringBuilder sb = new StringBuilder(64);
        for (Class<?> c : cs) {
            sb.append(getDesc(c));
        }
        return sb.toString();
    }

    /**
     * get method desc.
     * int do(int arg1) => "do(I)I"
     * void do(String arg1,boolean arg2) => "do(Ljava/lang/String;Z)V"
     *
     * @param m method.
     * @return desc.
     */
    public static String getDesc(final Method m) {
        StringBuilder ret = new StringBuilder(m.getName()).append('(');
        Class<?>[] parameterTypes = m.getParameterTypes();
        for (int i = 0; i < parameterTypes.length; i++) {
            ret.append(getDesc(parameterTypes[i]));
        }
        ret.append(')').append(getDesc(m.getReturnType()));
        return ret.toString();
    }

    public static String[] getDescArray(final Method m) {
        Class<?>[] parameterTypes = m.getParameterTypes();
        String[] arr = new String[parameterTypes.length];

        for (int i = 0; i < parameterTypes.length; i++) {
            arr[i] = getDesc(parameterTypes[i]);
        }
        return arr;
    }

    /**
     * get constructor desc.
     * "()V", "(Ljava/lang/String;I)V"
     *
     * @param c constructor.
     * @return desc
     */
    public static String getDesc(final Constructor<?> c) {
        StringBuilder ret = new StringBuilder("(");
        Class<?>[] parameterTypes = c.getParameterTypes();
        for (int i = 0; i < parameterTypes.length; i++) {
            ret.append(getDesc(parameterTypes[i]));
        }
        ret.append(')').append('V');
        return ret.toString();
    }

    /**
     * get method desc.
     * "(I)I", "()V", "(Ljava/lang/String;Z)V"
     *
     * @param m method.
     * @return desc.
     */
    public static String getDescWithoutMethodName(Method m) {
        StringBuilder ret = new StringBuilder();
        ret.append('(');
        Class<?>[] parameterTypes = m.getParameterTypes();
        for (int i = 0; i < parameterTypes.length; i++) {
            ret.append(getDesc(parameterTypes[i]));
        }
        ret.append(')').append(getDesc(m.getReturnType()));
        return ret.toString();
    }

    /**
     * get class desc.
     * Object.class => "Ljava/lang/Object;"
     * boolean[].class => "[Z"
     *
     * @param c class.
     * @return desc.
     * @throws NotFoundException
     */
    public static String getDesc(final CtClass c) throws NotFoundException {
        StringBuilder ret = new StringBuilder();
        if (c.isArray()) {
            ret.append('[');
            ret.append(getDesc(c.getComponentType()));
        } else if (c.isPrimitive()) {
            String t = c.getName();
            if ("void".equals(t)) {
                ret.append(JVM_VOID);
            } else if ("boolean".equals(t)) {
                ret.append(JVM_BOOLEAN);
            } else if ("byte".equals(t)) {
                ret.append(JVM_BYTE);
            } else if ("char".equals(t)) {
                ret.append(JVM_CHAR);
            } else if ("double".equals(t)) {
                ret.append(JVM_DOUBLE);
            } else if ("float".equals(t)) {
                ret.append(JVM_FLOAT);
            } else if ("int".equals(t)) {
                ret.append(JVM_INT);
            } else if ("long".equals(t)) {
                ret.append(JVM_LONG);
            } else if ("short".equals(t)) {
                ret.append(JVM_SHORT);
            }
        } else {
            ret.append('L');
            ret.append(c.getName().replace('.', '/'));
            ret.append(';');
        }
        return ret.toString();
    }

    /**
     * get method desc.
     * "do(I)I", "do()V", "do(Ljava/lang/String;Z)V"
     *
     * @param m method.
     * @return desc.
     */
    public static String getDesc(final CtMethod m) throws NotFoundException {
        StringBuilder ret = new StringBuilder(m.getName()).append('(');
        CtClass[] parameterTypes = m.getParameterTypes();
        for (CtClass parameterType : parameterTypes) {
            ret.append(getDesc(parameterType));
        }
        ret.append(')').append(getDesc(m.getReturnType()));
        return ret.toString();
    }

    /**
     * get constructor desc.
     * "()V", "(Ljava/lang/String;I)V"
     *
     * @param c constructor.
     * @return desc
     */
    public static String getDesc(final CtConstructor c) throws NotFoundException {
        StringBuilder ret = new StringBuilder("(");
        CtClass[] parameterTypes = c.getParameterTypes();
        for (int i = 0; i < parameterTypes.length; i++) {
            ret.append(getDesc(parameterTypes[i]));
        }
        ret.append(')').append('V');
        return ret.toString();
    }

    /**
     * get method desc.
     * "(I)I", "()V", "(Ljava/lang/String;Z)V".
     *
     * @param m method.
     * @return desc.
     */
    public static String getDescWithoutMethodName(final CtMethod m) throws NotFoundException {
        StringBuilder ret = new StringBuilder();
        ret.append('(');
        CtClass[] parameterTypes = m.getParameterTypes();
        for (int i = 0; i < parameterTypes.length; i++) {
            ret.append(getDesc(parameterTypes[i]));
        }
        ret.append(')').append(getDesc(m.getReturnType()));
        return ret.toString();
    }

    /**
     * name to desc.
     * java.util.Map[][] => "[[Ljava/util/Map;"
     *
     * @param name name.
     * @return desc.
     */
    public static String name2desc(String name) {
        StringBuilder sb = new StringBuilder();
        int c = 0, index = name.indexOf('[');
        if (index > 0) {
            c = (name.length() - index) / 2;
            name = name.substring(0, index);
        }
        while (c-- > 0) {
            sb.append('[');
        }
        if ("void".equals(name)) {
            sb.append(JVM_VOID);
        } else if ("boolean".equals(name)) {
            sb.append(JVM_BOOLEAN);
        } else if ("byte".equals(name)) {
            sb.append(JVM_BYTE);
        } else if ("char".equals(name)) {
            sb.append(JVM_CHAR);
        } else if ("double".equals(name)) {
            sb.append(JVM_DOUBLE);
        } else if ("float".equals(name)) {
            sb.append(JVM_FLOAT);
        } else if ("int".equals(name)) {
            sb.append(JVM_INT);
        } else if ("long".equals(name)) {
            sb.append(JVM_LONG);
        } else if ("short".equals(name)) {
            sb.append(JVM_SHORT);
        } else {
            sb.append('L').append(name.replace('.', '/')).append(';');
        }
        return sb.toString();
    }

    /**
     * desc to name.
     * "[[I" => "int[][]"
     *
     * @param desc desc.
     * @return name.
     */
    public static String desc2name(String desc) {
        StringBuilder sb = new StringBuilder();
        int c = desc.lastIndexOf('[') + 1;
        if (desc.length() == c + 1) {
            switch (desc.charAt(c)) {
                case JVM_VOID: {
                    sb.append("void");
                    break;
                }
                case JVM_BOOLEAN: {
                    sb.append("boolean");
                    break;
                }
                case JVM_BYTE: {
                    sb.append("byte");
                    break;
                }
                case JVM_CHAR: {
                    sb.append("char");
                    break;
                }
                case JVM_DOUBLE: {
                    sb.append("double");
                    break;
                }
                case JVM_FLOAT: {
                    sb.append("float");
                    break;
                }
                case JVM_INT: {
                    sb.append("int");
                    break;
                }
                case JVM_LONG: {
                    sb.append("long");
                    break;
                }
                case JVM_SHORT: {
                    sb.append("short");
                    break;
                }
                default:
                    throw new RuntimeException();
            }
        } else {
            sb.append(desc.substring(c + 1, desc.length() - 1).replace('/', '.'));
        }
        while (c-- > 0) {
            sb.append("[]");
        }
        return sb.toString();
    }

    public static Class<?> forName(String name) {
        try {
            return name2class(name);
        } catch (ClassNotFoundException e) {
            throw new IllegalStateException("Not found class " + name + ", cause: " + e.getMessage(), e);
        }
    }

    public static Class<?> forName(ClassLoader cl, String name) {
        try {
            return name2class(cl, name);
        } catch (ClassNotFoundException e) {
            throw new IllegalStateException("Not found class " + name + ", cause: " + e.getMessage(), e);
        }
    }

    /**
     * name to class.
     * "boolean" => boolean.class
     * "java.util.Map[][]" => java.util.Map[][].class
     *
     * @param name name.
     * @return Class instance.
     */
    public static Class<?> name2class(String name) throws ClassNotFoundException {
        return name2class(ClassUtils.getClassLoader(), name);
    }

    /**
     * name to class.
     * "boolean" => boolean.class
     * "java.util.Map[][]" => java.util.Map[][].class
     *
     * @param cl   ClassLoader instance.
     * @param name name.
     * @return Class instance.
     */
    private static Class<?> name2class(ClassLoader cl, String name) throws ClassNotFoundException {
        int c = 0, index = name.indexOf('[');
        if (index > 0) {
            c = (name.length() - index) / 2;
            name = name.substring(0, index);
        }
        if (c > 0) {
            StringBuilder sb = new StringBuilder();
            while (c-- > 0) {
                sb.append('[');
            }

            if ("void".equals(name)) {
                sb.append(JVM_VOID);
            } else if ("boolean".equals(name)) {
                sb.append(JVM_BOOLEAN);
            } else if ("byte".equals(name)) {
                sb.append(JVM_BYTE);
            } else if ("char".equals(name)) {
                sb.append(JVM_CHAR);
            } else if ("double".equals(name)) {
                sb.append(JVM_DOUBLE);
            } else if ("float".equals(name)) {
                sb.append(JVM_FLOAT);
            } else if ("int".equals(name)) {
                sb.append(JVM_INT);
            } else if ("long".equals(name)) {
                sb.append(JVM_LONG);
            } else if ("short".equals(name)) {
                sb.append(JVM_SHORT);
            } else {
                // "java.lang.Object" ==> "Ljava.lang.Object;"
                sb.append('L').append(name).append(';');
            }
            name = sb.toString();
        } else {
            if ("void".equals(name)) {
                return void.class;
            }
            if ("boolean".equals(name)) {
                return boolean.class;
            }
            if ("byte".equals(name)) {
                return byte.class;
            }
            if ("char".equals(name)) {
                return char.class;
            }
            if ("double".equals(name)) {
                return double.class;
            }
            if ("float".equals(name)) {
                return float.class;
            }
            if ("int".equals(name)) {
                return int.class;
            }
            if ("long".equals(name)) {
                return long.class;
            }
            if ("short".equals(name)) {
                return short.class;
            }
        }

        if (cl == null) {
            cl = ClassUtils.getClassLoader();
        }
        return Class.forName(name, true, cl);
    }

    /**
     * desc to class.
     * "[Z" => boolean[].class
     * "[[Ljava/util/Map;" => java.util.Map[][].class
     *
     * @param desc desc.
     * @return Class instance.
     * @throws ClassNotFoundException
     */
    public static Class<?> desc2class(String desc) throws ClassNotFoundException {
        return desc2class(ClassUtils.getClassLoader(), desc);
    }

    /**
     * desc to class.
     * "[Z" => boolean[].class
     * "[[Ljava/util/Map;" => java.util.Map[][].class
     *
     * @param cl   ClassLoader instance.
     * @param desc desc.
     * @return Class instance.
     * @throws ClassNotFoundException
     */
    private static Class<?> desc2class(ClassLoader cl, String desc) throws ClassNotFoundException {
        switch (desc.charAt(0)) {
            case JVM_VOID:
                return void.class;
            case JVM_BOOLEAN:
                return boolean.class;
            case JVM_BYTE:
                return byte.class;
            case JVM_CHAR:
                return char.class;
            case JVM_DOUBLE:
                return double.class;
            case JVM_FLOAT:
                return float.class;
            case JVM_INT:
                return int.class;
            case JVM_LONG:
                return long.class;
            case JVM_SHORT:
                return short.class;
            case 'L':
                // "Ljava/lang/Object;" ==> "java.lang.Object"
                desc = desc.substring(1, desc.length() - 1).replace('/', '.');
                break;
            case '[':
                // "[[Ljava/lang/Object;" ==> "[[Ljava.lang.Object;"
                desc = desc.replace('/', '.');
                break;
            default:
                throw new ClassNotFoundException("Class not found: " + desc);
        }

        if (cl == null) {
            cl = ClassUtils.getClassLoader();
        }
        return Class.forName(desc, true, cl);
    }

    /**
     * get class array instance.
     *
     * @param desc desc.
     * @return Class class array.
     * @throws ClassNotFoundException
     */
    public static Class<?>[] desc2classArray(String desc) throws ClassNotFoundException {
        Class<?>[] ret = desc2classArray(ClassUtils.getClassLoader(), desc);
        return ret;
    }

    /**
     * get class array instance.
     *
     * @param cl   ClassLoader instance.
     * @param desc desc.
     * @return Class[] class array.
     * @throws ClassNotFoundException
     */
    private static Class<?>[] desc2classArray(ClassLoader cl, String desc) throws ClassNotFoundException {
        if (desc.length() == 0) {
            return EMPTY_CLASS_ARRAY;
        }

        List<Class<?>> cs = new ArrayList<Class<?>>();
        Matcher m = DESC_PATTERN.matcher(desc);
        while (m.find()) {
            cs.add(desc2class(cl, m.group()));
        }
        return cs.toArray(EMPTY_CLASS_ARRAY);
    }

    /**
     * Find method from method signature
     *
     * @param clazz      Target class to find method
     * @param methodName Method signature, e.g.: method1(int, String). It is allowed to provide method name only, e.g.: method2
     * @return target method
     * @throws NoSuchMethodException
     * @throws ClassNotFoundException
     * @throws IllegalStateException  when multiple methods are found (overridden method when parameter info is not provided)
     * @deprecated Recommend {@link MethodUtils#findMethod(Class, String, Class[])}
     */
    @Deprecated
    public static Method findMethodByMethodSignature(Class<?> clazz, String methodName, String[] parameterTypes)
            throws NoSuchMethodException, ClassNotFoundException {
        String signature = clazz.getName() + "." + methodName;
        if (parameterTypes != null && parameterTypes.length > 0) {
            signature += StringUtils.join(parameterTypes);
        }
        Method method;
        if (parameterTypes == null) {
            List<Method> finded = new ArrayList<Method>();
            for (Method m : clazz.getMethods()) {
                if (m.getName().equals(methodName)) {
                    finded.add(m);
                }
            }
            if (finded.isEmpty()) {
                throw new NoSuchMethodException("No such method " + methodName + " in class " + clazz);
            }
            if (finded.size() > 1) {
                String msg = String.format("Not unique method for method name(%s) in class(%s), find %d methods.",
                        methodName, clazz.getName(), finded.size());
                throw new IllegalStateException(msg);
            }
            method = finded.get(0);
        } else {
            Class<?>[] types = new Class<?>[parameterTypes.length];
            for (int i = 0; i < parameterTypes.length; i++) {
                types[i] = ReflectUtils.name2class(parameterTypes[i]);
            }
            method = clazz.getMethod(methodName, types);

        }
        return method;
    }

    /**
     * @param clazz      Target class to find method
     * @param methodName Method signature, e.g.: method1(int, String). It is allowed to provide method name only, e.g.: method2
     * @return target method
     * @throws NoSuchMethodException
     * @throws ClassNotFoundException
     * @throws IllegalStateException  when multiple methods are found (overridden method when parameter info is not provided)
     * @deprecated Recommend {@link MethodUtils#findMethod(Class, String, Class[])}
     */
    @Deprecated
    public static Method findMethodByMethodName(Class<?> clazz, String methodName)
            throws NoSuchMethodException, ClassNotFoundException {
        return findMethodByMethodSignature(clazz, methodName, null);
    }

    public static Constructor<?> findConstructor(Class<?> clazz, Class<?> paramType) throws NoSuchMethodException {
        Constructor<?> targetConstructor;
        try {
            targetConstructor = clazz.getConstructor(new Class<?>[]{paramType});
        } catch (NoSuchMethodException e) {
            targetConstructor = null;
            Constructor<?>[] constructors = clazz.getConstructors();
            for (Constructor<?> constructor : constructors) {
                if (Modifier.isPublic(constructor.getModifiers())
                        && constructor.getParameterTypes().length == 1
                        && constructor.getParameterTypes()[0].isAssignableFrom(paramType)) {
                    targetConstructor = constructor;
                    break;
                }
            }
            if (targetConstructor == null) {
                throw e;
            }
        }
        return targetConstructor;
    }

    /**
     * Check if one object is the implementation for a given interface.
     * <p>
     * This method will not trigger classloading for the given interface, therefore it will not lead to error when
     * the given interface is not visible by the classloader
     *
     * @param obj                Object to examine
     * @param interfaceClazzName The given interface
     * @return true if the object implements the given interface, otherwise return false
     */
    public static boolean isInstance(Object obj, String interfaceClazzName) {
        for (Class<?> clazz = obj.getClass();
             clazz != null && !clazz.equals(Object.class);
             clazz = clazz.getSuperclass()) {
            Class<?>[] interfaces = clazz.getInterfaces();
            for (Class<?> itf : interfaces) {
                if (itf.getName().equals(interfaceClazzName)) {
                    return true;
                }
            }
        }
        return false;
    }

    public static Object getEmptyObject(Class<?> returnType) {
        return getEmptyObject(returnType, new HashMap<>(), 0);
    }

    private static Object getEmptyObject(Class<?> returnType, Map<Class<?>, Object> emptyInstances, int level) {
        if (level > 2) {
            return null;
        }
        if (returnType == null) {
            return null;
        }
        if (returnType == boolean.class || returnType == Boolean.class) {
            return false;
        }
        if (returnType == char.class || returnType == Character.class) {
            return '\0';
        }
        if (returnType == byte.class || returnType == Byte.class) {
            return (byte) 0;
        }
        if (returnType == short.class || returnType == Short.class) {
            return (short) 0;
        }
        if (returnType == int.class || returnType == Integer.class) {
            return 0;
        }
        if (returnType == long.class || returnType == Long.class) {
            return 0L;
        }
        if (returnType == float.class || returnType == Float.class) {
            return 0F;
        }
        if (returnType == double.class || returnType == Double.class) {
            return 0D;
        }
        if (returnType.isArray()) {
            return Array.newInstance(returnType.getComponentType(), 0);
        }
        if (returnType.isAssignableFrom(ArrayList.class)) {
            return new ArrayList<>(0);
        }
        if (returnType.isAssignableFrom(HashSet.class)) {
            return new HashSet<>(0);
        }
        if (returnType.isAssignableFrom(HashMap.class)) {
            return new HashMap<>(0);
        }
        if (String.class.equals(returnType)) {
            return "";
        }
        if (returnType.isInterface()) {
            return null;
        }

        try {
            Object value = emptyInstances.get(returnType);
            if (value == null) {
                value = returnType.getDeclaredConstructor().newInstance();
                emptyInstances.put(returnType, value);
            }
            Class<?> cls = value.getClass();
            while (cls != null && cls != Object.class) {
                Field[] fields = cls.getDeclaredFields();
                for (Field field : fields) {
                    if (field.isSynthetic()) {
                        continue;
                    }
                    Object property = getEmptyObject(field.getType(), emptyInstances, level + 1);
                    if (property != null) {
                        try {
                            if (!field.isAccessible()) {
                                field.setAccessible(true);
                            }
                            field.set(value, property);
                        } catch (Throwable ignored) {
                        }
                    }
                }
                cls = cls.getSuperclass();
            }
            return value;
        } catch (Throwable e) {
            return null;
        }
    }

    public static Object defaultReturn(Method m) {
        if (m.getReturnType().isPrimitive()) {
            return primitiveDefaults.get(m.getReturnType());
        } else {
            return null;
        }
    }

    public static Object defaultReturn(Class<?> classType) {
        if (classType != null && classType.isPrimitive()) {
            return primitiveDefaults.get(classType);
        } else {
            return null;
        }
    }

    public static boolean isBeanPropertyReadMethod(Method method) {
        return method != null
                && Modifier.isPublic(method.getModifiers())
                && !Modifier.isStatic(method.getModifiers())
                && method.getReturnType() != void.class
                && method.getDeclaringClass() != Object.class
                && method.getParameterTypes().length == 0
                && ((method.getName().startsWith("get") && method.getName().length() > 3)
                || (method.getName().startsWith("is") && method.getName().length() > 2));
    }

    public static String getPropertyNameFromBeanReadMethod(Method method) {
        if (isBeanPropertyReadMethod(method)) {
            if (method.getName().startsWith("get")) {
                return method.getName().substring(3, 4).toLowerCase()
                        + method.getName().substring(4);
            }
            if (method.getName().startsWith("is")) {
                return method.getName().substring(2, 3).toLowerCase()
                        + method.getName().substring(3);
            }
        }
        return null;
    }

    public static boolean isBeanPropertyWriteMethod(Method method) {
        return method != null
                && Modifier.isPublic(method.getModifiers())
                && !Modifier.isStatic(method.getModifiers())
                && method.getDeclaringClass() != Object.class
                && method.getParameterTypes().length == 1
                && method.getName().startsWith("set")
                && method.getName().length() > 3;
    }

    public static String getPropertyNameFromBeanWriteMethod(Method method) {
        if (isBeanPropertyWriteMethod(method)) {
            return method.getName().substring(3, 4).toLowerCase()
                    + method.getName().substring(4);
        }
        return null;
    }

    public static boolean isPublicInstanceField(Field field) {
        return Modifier.isPublic(field.getModifiers())
                && !Modifier.isStatic(field.getModifiers())
                && !Modifier.isFinal(field.getModifiers())
                && !field.isSynthetic();
    }

    public static Map<String, Field> getBeanPropertyFields(Class cl) {
        Map<String, Field> properties = new HashMap<String, Field>();
        for (; cl != null; cl = cl.getSuperclass()) {
            Field[] fields = cl.getDeclaredFields();
            for (Field field : fields) {
                if (Modifier.isTransient(field.getModifiers())
                        || Modifier.isStatic(field.getModifiers())) {
                    continue;
                }

                field.setAccessible(true);

                properties.put(field.getName(), field);
            }
        }

        return properties;
    }

    public static Map<String, Method> getBeanPropertyReadMethods(Class cl) {
        Map<String, Method> properties = new HashMap<String, Method>();
        for (; cl != null; cl = cl.getSuperclass()) {
            Method[] methods = cl.getDeclaredMethods();
            for (Method method : methods) {
                if (isBeanPropertyReadMethod(method)) {
                    method.setAccessible(true);
                    String property = getPropertyNameFromBeanReadMethod(method);
                    properties.put(property, method);
                }
            }
        }

        return properties;
    }

    public static Type[] getReturnTypes(Method method) {
        Class<?> returnType = method.getReturnType();
        Type genericReturnType = method.getGenericReturnType();
        if (Future.class.isAssignableFrom(returnType)) {
            if (genericReturnType instanceof ParameterizedType) {
                Type actualArgType = ((ParameterizedType) genericReturnType).getActualTypeArguments()[0];
                if (actualArgType instanceof ParameterizedType) {
                    returnType = (Class<?>) ((ParameterizedType) actualArgType).getRawType();
                    genericReturnType = actualArgType;
                } else if (actualArgType instanceof TypeVariable) {
                    returnType = (Class<?>) ((TypeVariable<?>) actualArgType).getBounds()[0];
                    genericReturnType = actualArgType;
                } else {
                    returnType = (Class<?>) actualArgType;
                    genericReturnType = returnType;
                }
            } else {
                returnType = null;
                genericReturnType = null;
            }
        }
        return new Type[]{returnType, genericReturnType};
    }

    /**
     * Find the {@link Set} of {@link ParameterizedType}
     *
     * @param sourceClass the source {@link Class class}
     * @return non-null read-only {@link Set}
     * @since 2.7.5
     */
    public static Set<ParameterizedType> findParameterizedTypes(Class<?> sourceClass) {
        // Add Generic Interfaces
        List<Type> genericTypes = new LinkedList<>(asList(sourceClass.getGenericInterfaces()));
        // Add Generic Super Class
        genericTypes.add(sourceClass.getGenericSuperclass());

        Set<ParameterizedType> parameterizedTypes = genericTypes.stream()
                .filter(type -> type instanceof ParameterizedType)// filter ParameterizedType
                .map(ParameterizedType.class::cast)  // cast to ParameterizedType
                .collect(Collectors.toSet());

        if (parameterizedTypes.isEmpty()) { // If not found, try to search super types recursively
            genericTypes.stream()
                    .filter(type -> type instanceof Class)
                    .map(Class.class::cast)
                    .forEach(superClass -> parameterizedTypes.addAll(findParameterizedTypes(superClass)));
        }

        return unmodifiableSet(parameterizedTypes);                     // build as a Set

    }

    /**
     * Find the hierarchical types from the source {@link Class class} by specified {@link Class type}.
     *
     * @param sourceClass the source {@link Class class}
     * @param matchType   the type to match
     * @param <T>         the type to match
     * @return non-null read-only {@link Set}
     * @since 2.7.5
     */
    public static <T> Set<Class<T>> findHierarchicalTypes(Class<?> sourceClass, Class<T> matchType) {
        if (sourceClass == null) {
            return Collections.emptySet();
        }

        Set<Class<T>> hierarchicalTypes = new LinkedHashSet<>();

        if (matchType.isAssignableFrom(sourceClass)) {
            hierarchicalTypes.add((Class<T>) sourceClass);
        }

        // Find all super classes
        hierarchicalTypes.addAll(findHierarchicalTypes(sourceClass.getSuperclass(), matchType));

        return unmodifiableSet(hierarchicalTypes);
    }

    /**
     * Get the value from the specified bean and its getter method.
     *
     * @param bean       the bean instance
     * @param methodName the name of getter
     * @param <T>        the type of property value
     * @return
     * @since 2.7.5
     */
    public static <T> T getProperty(Object bean, String methodName) {
        Class<?> beanClass = bean.getClass();
        BeanInfo beanInfo = null;
        T propertyValue = null;

        try {
            beanInfo = Introspector.getBeanInfo(beanClass);
            propertyValue = (T) Stream.of(beanInfo.getMethodDescriptors())
                    .filter(methodDescriptor -> methodName.equals(methodDescriptor.getName()))
                    .findFirst()
                    .map(method -> {
                        try {
                            return method.getMethod().invoke(bean);
                        } catch (Exception e) {
                            //ignore
                        }
                        return null;
                    }).get();
        } catch (Exception e) {

        }
        return propertyValue;
    }

    /**
     * Check target bean class whether has specify method
     * @param beanClass
     * @param methodName
     * @return
     */
    public static boolean hasMethod(Class<?> beanClass, String methodName) {
        try {
            BeanInfo beanInfo = Introspector.getBeanInfo(beanClass);
            Optional<MethodDescriptor> descriptor = Stream.of(beanInfo.getMethodDescriptors())
                    .filter(methodDescriptor -> methodName.equals(methodDescriptor.getName()))
                    .findFirst();
            return descriptor.isPresent();
        } catch (Exception e) {

        }
        return false;
    }

    /**
     * Resolve the types of the specified values
     *
     * @param values the values
     * @return If can't be resolved, return {@link ReflectUtils#EMPTY_CLASS_ARRAY empty class array}
     * @since 2.7.6
     */
    public static Class[] resolveTypes(Object... values) {

        if (isEmpty(values)) {
            return EMPTY_CLASS_ARRAY;
        }

        int size = values.length;

        Class[] types = new Class[size];

        for (int i = 0; i < size; i++) {
            Object value = values[i];
            types[i] = value == null ? null : value.getClass();
        }

        return types;
    }

    public static boolean checkZeroArgConstructor(Class clazz) {
        try {
            clazz.getDeclaredConstructor();
            return true;
        } catch (NoSuchMethodException e) {
            return false;
        }
    }

    public static boolean isJdk(Class clazz) {
        return clazz.getName().startsWith("java.") || clazz.getName().startsWith("javax.");
    }

    /**
     * Copy from org.springframework.util.ReflectionUtils.
     * Make the given method accessible, explicitly setting it accessible if
     * necessary. The {@code setAccessible(true)} method is only called
     * when actually necessary, to avoid unnecessary conflicts with a JVM
     * SecurityManager (if active).
     * @param method the method to make accessible
     * @see java.lang.reflect.Method#setAccessible
     */
    @SuppressWarnings("deprecation")  // on JDK 9
    public static void makeAccessible(Method method) {
        if ((!Modifier.isPublic(method.getModifiers()) ||
                !Modifier.isPublic(method.getDeclaringClass().getModifiers())) && !method.isAccessible()) {
            method.setAccessible(true);
        }
    }

    /**
     * Get all field names of target type
     * @param type
     * @return
     */
    public static Set<String> getAllFieldNames(Class<?> type) {

        Set<String> fieldNames = new HashSet<>();
        for (Field field : type.getDeclaredFields()) {
            fieldNames.add(field.getName());
        }

        Set<Class<?>> allSuperClasses = ClassUtils.getAllSuperClasses(type);
        for (Class<?> aClass : allSuperClasses) {
            for (Field field : aClass.getDeclaredFields()) {
                fieldNames.add(field.getName());
            }
        }
        return fieldNames;
    }

    public static <T> T getFieldValue(Object obj, String fieldName) throws RuntimeException {
        if (obj == null) {
            throw new IllegalArgumentException("object is null");
        }
        try {
            Field field = obj.getClass().getDeclaredField(fieldName);
            field.setAccessible(true);
            return (T) field.get(obj);
        } catch (Exception e) {
            throw new RuntimeException(e.getMessage(), e);
        }
    }
}

相关信息

dubbo 源码目录

相关文章

dubbo AnnotationUtils 源码

dubbo ArrayUtils 源码

dubbo Assert 源码

dubbo AtomicPositiveInteger 源码

dubbo CIDRUtils 源码

dubbo CharSequenceComparator 源码

dubbo ClassHelper 源码

dubbo ClassLoaderResourceLoader 源码

dubbo ClassUtils 源码

dubbo CollectionUtils 源码

0  赞