001/*
002 *  Copyright (c) 2022-2023, Mybatis-Flex (fuhai999@gmail.com).
003 *  <p>
004 *  Licensed under the Apache License, Version 2.0 (the "License");
005 *  you may not use this file except in compliance with the License.
006 *  You may obtain a copy of the License at
007 *  <p>
008 *  http://www.apache.org/licenses/LICENSE-2.0
009 *  <p>
010 *  Unless required by applicable law or agreed to in writing, software
011 *  distributed under the License is distributed on an "AS IS" BASIS,
012 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 *  See the License for the specific language governing permissions and
014 *  limitations under the License.
015 */
016package com.mybatisflex.core.util;
017
018
019import org.apache.ibatis.javassist.util.proxy.ProxyObject;
020
021import java.lang.reflect.*;
022import java.util.ArrayList;
023import java.util.Arrays;
024import java.util.List;
025import java.util.function.Predicate;
026
027/**
028 * 类实例创建者创建者
029 *
030 * @author michael
031 * @date 17/3/21
032 */
033@SuppressWarnings("unchecked")
034public class ClassUtil {
035
036    private ClassUtil() {
037    }
038
039    private static final String[] OBJECT_METHODS = new String[]{
040        "toString",
041        "getClass",
042        "equals",
043        "hashCode",
044        "wait",
045        "notify",
046        "notifyAll",
047        "clone",
048        "finalize"
049    };
050
051    //proxy frameworks
052    private static final List<String> PROXY_CLASS_NAMES = Arrays.asList("net.sf.cglib.proxy.Factory"
053        // cglib
054        , "org.springframework.cglib.proxy.Factory"
055
056        // javassist
057        , "javassist.util.proxy.ProxyObject"
058        , "org.apache.ibatis.javassist.util.proxy.ProxyObject");
059    private static final String ENHANCER_BY = "$$EnhancerBy";
060    private static final String JAVASSIST_BY = "_$$_";
061
062    public static boolean isProxy(Class<?> clazz) {
063        for (Class<?> cls : clazz.getInterfaces()) {
064            if (PROXY_CLASS_NAMES.contains(cls.getName())) {
065                return true;
066            }
067        }
068        //java proxy
069        return Proxy.isProxyClass(clazz);
070    }
071
072    public static <T> Class<T> getUsefulClass(Class<T> clazz) {
073        if (isProxy(clazz)) {
074            return getJdkProxySuperClass(clazz);
075        }
076
077//        if (ProxyObject.class.isAssignableFrom(clazz)){
078//            return (Class<T>) clazz.getSuperclass();
079//        }
080
081        //ControllerTest$ServiceTest$$EnhancerByGuice$$40471411#hello   -------> Guice
082        //com.demo.blog.Blog$$EnhancerByCGLIB$$69a17158  ----> CGLIB
083        //io.jboot.test.app.TestAppListener_$$_jvstb9f_0 ------> javassist
084        final String name = clazz.getName();
085        if (name.contains(ENHANCER_BY) || name.contains(JAVASSIST_BY)) {
086            return (Class<T>) clazz.getSuperclass();
087        }
088
089        return clazz;
090    }
091
092
093    public static Class<?> getWrapType(Class<?> clazz) {
094        if (clazz == null || !clazz.isPrimitive()) {
095            return clazz;
096        }
097        if (clazz == Integer.TYPE) {
098            return Integer.class;
099        } else if (clazz == Long.TYPE) {
100            return Long.class;
101        } else if (clazz == Boolean.TYPE) {
102            return Boolean.class;
103        } else if (clazz == Float.TYPE) {
104            return Float.class;
105        } else if (clazz == Double.TYPE) {
106            return Double.class;
107        } else if (clazz == Short.TYPE) {
108            return Short.class;
109        } else if (clazz == Character.TYPE) {
110            return Character.class;
111        } else if (clazz == Byte.TYPE) {
112            return Byte.class;
113        } else if (clazz == Void.TYPE) {
114            return Void.class;
115        }
116        return clazz;
117    }
118
119
120    public static boolean isArray(Class<?> clazz) {
121        return clazz.isArray()
122            || clazz == int[].class
123            || clazz == long[].class
124            || clazz == short[].class
125            || clazz == float[].class
126            || clazz == double[].class;
127    }
128
129    public static boolean canInstance(int mod) {
130        return !Modifier.isAbstract(mod) || !Modifier.isInterface(mod);
131    }
132
133
134    public static <T> T newInstance(Class<T> clazz) {
135        try {
136            Constructor<?> defaultConstructor = null;
137            Constructor<?> otherConstructor = null;
138
139            Constructor<?>[] declaredConstructors = clazz.getDeclaredConstructors();
140            for (Constructor<?> constructor : declaredConstructors) {
141                if (constructor.getParameterCount() == 0 && Modifier.isPublic(constructor.getModifiers())) {
142                    defaultConstructor = constructor;
143                } else if (Modifier.isPublic(constructor.getModifiers())) {
144                    otherConstructor = constructor;
145                }
146            }
147            if (defaultConstructor != null) {
148                return (T) defaultConstructor.newInstance();
149            } else if (otherConstructor != null) {
150                Class<?>[] parameterTypes = otherConstructor.getParameterTypes();
151                Object[] parameters = new Object[parameterTypes.length];
152                for (int i = 0; i < parameterTypes.length; i++) {
153                    if (parameterTypes[i].isPrimitive()) {
154                        parameters[i] = ConvertUtil.getPrimitiveDefaultValue(parameterTypes[i]);
155                    } else {
156                        parameters[i] = null;
157                    }
158                }
159                return (T) otherConstructor.newInstance(parameters);
160            }
161            // 没有任何构造函数的情况下，去查找 static 工厂方法，满足 lombok 注解的需求
162            else {
163                Method factoryMethod = ClassUtil.getFirstMethod(clazz, m -> m.getParameterCount() == 0
164                    && clazz == m.getReturnType()
165                    && Modifier.isPublic(m.getModifiers())
166                    && Modifier.isStatic(m.getModifiers()));
167                if (factoryMethod != null) {
168                    return (T) factoryMethod.invoke(null);
169                }
170            }
171            throw new IllegalArgumentException("the class \"" + clazz.getName() + "\" has no constructor.");
172        } catch (Exception e) {
173            throw new RuntimeException("Can not newInstance class: " + clazz.getName());
174        }
175    }
176
177
178    public static <T> T newInstance(Class<T> clazz, Object... paras) {
179        try {
180            Constructor<?>[] constructors = clazz.getDeclaredConstructors();
181            for (Constructor<?> constructor : constructors) {
182                if (isMatchedParas(constructor, paras)) {
183                    Object ret = constructor.newInstance(paras);
184                    return (T) ret;
185                }
186            }
187            throw new IllegalArgumentException("Can not find constructor by paras: \"" + Arrays.toString(paras) + "\" in class[" + clazz.getName() + "]");
188        } catch (Exception e) {
189            e.printStackTrace();
190        }
191
192        return null;
193    }
194
195
196    private static boolean isMatchedParas(Constructor<?> constructor, Object[] paras) {
197        if (constructor.getParameterCount() == 0) {
198            return paras == null || paras.length == 0;
199        }
200
201        if (constructor.getParameterCount() > 0
202            && (paras == null || paras.length != constructor.getParameterCount())) {
203            return false;
204        }
205
206        Class<?>[] parameterTypes = constructor.getParameterTypes();
207        for (int i = 0; i < parameterTypes.length; i++) {
208            Class<?> parameterType = parameterTypes[i];
209            Object paraObject = paras[i];
210            if (paraObject != null && !parameterType.isAssignableFrom(paraObject.getClass())) {
211                return false;
212            }
213        }
214
215        return true;
216    }
217
218
219    public static List<Field> getAllFields(Class<?> clazz) {
220        List<Field> fields = new ArrayList<>();
221        doGetFields(clazz, fields, null, false);
222        return fields;
223    }
224
225    public static List<Field> getAllFields(Class<?> clazz, Predicate<Field> predicate) {
226        List<Field> fields = new ArrayList<>();
227        doGetFields(clazz, fields, predicate, false);
228        return fields;
229    }
230
231    public static Field getFirstField(Class<?> clazz, Predicate<Field> predicate) {
232        List<Field> fields = new ArrayList<>();
233        doGetFields(clazz, fields, predicate, true);
234        return fields.isEmpty() ? null : fields.get(0);
235    }
236
237    private static void doGetFields(Class<?> clazz, List<Field> fields, Predicate<Field> predicate, boolean firstOnly) {
238        if (clazz == null || clazz == Object.class) {
239            return;
240        }
241
242        Field[] declaredFields = clazz.getDeclaredFields();
243        for (Field declaredField : declaredFields) {
244            if (predicate == null || predicate.test(declaredField)) {
245                fields.add(declaredField);
246                if (firstOnly) {
247                    break;
248                }
249            }
250        }
251
252        if (firstOnly && !fields.isEmpty()) {
253            return;
254        }
255
256        doGetFields(clazz.getSuperclass(), fields, predicate, firstOnly);
257    }
258
259    public static List<Method> getAllMethods(Class<?> clazz) {
260        List<Method> methods = new ArrayList<>();
261        doGetMethods(clazz, methods, null, false);
262        return methods;
263    }
264
265    public static List<Method> getAllMethods(Class<?> clazz, Predicate<Method> predicate) {
266        List<Method> methods = new ArrayList<>();
267        doGetMethods(clazz, methods, predicate, false);
268        return methods;
269    }
270
271    public static Method getAnyMethod(Class<?> clazz, String... methodNames) {
272        return getFirstMethod(clazz, method -> ArrayUtil.contains(methodNames, method.getName()));
273    }
274
275    public static Method getFirstMethod(Class<?> clazz, Predicate<Method> predicate) {
276        List<Method> methods = new ArrayList<>();
277        doGetMethods(clazz, methods, predicate, true);
278        return methods.isEmpty() ? null : methods.get(0);
279    }
280
281
282    private static void doGetMethods(Class<?> clazz, List<Method> methods, Predicate<Method> predicate, boolean firstOnly) {
283        if (clazz == null || clazz == Object.class) {
284            return;
285        }
286
287        Method[] declaredMethods = clazz.getDeclaredMethods();
288        for (Method method : declaredMethods) {
289            if (predicate == null || predicate.test(method)) {
290                methods.add(method);
291                if (firstOnly) {
292                    break;
293                }
294            }
295        }
296
297        if (firstOnly && !methods.isEmpty()) {
298            return;
299        }
300
301        doGetMethods(clazz.getSuperclass(), methods, predicate, firstOnly);
302    }
303
304
305    private static <T> Class<T> getJdkProxySuperClass(Class<T> clazz) {
306        final Class<?> proxyClass = Proxy.getProxyClass(clazz.getClassLoader(), clazz.getInterfaces());
307        return (Class<T>) proxyClass.getInterfaces()[0];
308    }
309
310
311    public static boolean isGetterMethod(Method method, String property) {
312        String methodName = method.getName();
313        if (methodName.startsWith("get") && methodName.length() > 3) {
314            return StringUtil.firstCharToUpperCase(property).equals(methodName.substring(3));
315        } else if (methodName.startsWith("is") && methodName.length() > 2) {
316            return StringUtil.firstCharToUpperCase(property).equals(methodName.substring(2));
317        } else {
318            return false;
319        }
320    }
321
322    public static boolean isObjectMethod(String methodName) {
323        return ArrayUtil.contains(OBJECT_METHODS, methodName);
324    }
325
326}