导入相关工具加入

nafmii-common/src/main/java/org/nafmii/common/excle/Reflections.java

+package org.nafmii.common.excle;
+
+import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.lang3.Validate;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.util.Assert;
+
+import java.lang.reflect.*;
+
+/**
+ * 反射工具类.
+ * 提供调用getter/setter方法, 访问私有变量, 调用私有方法, 获取泛型类型Class, 被AOP过的真实类等工具函数.
+ *
+ * @author calvin
+ * @version 2013-01-15
+ */
+@SuppressWarnings("rawtypes")
+public class Reflections {
+
+    private static final String SETTER_PREFIX = "set";
+
+    private static final String GETTER_PREFIX = "get";
+
+    private static final String CGLIB_CLASS_SEPARATOR = "$$";
+
+    private static Logger logger = LoggerFactory.getLogger(Reflections.class);
+
+    /**
+     * 调用Getter方法.
+     * 支持多级，如：对象名.对象名.方法
+     */
+    public static Object invokeGetter(Object obj, String propertyName) {
+        Object object = obj;
+        for (String name : StringUtils.split(propertyName, ".")) {
+            String getterMethodName = GETTER_PREFIX + StringUtils.capitalize(name);
+            object = invokeMethod(object, getterMethodName, new Class[]{}, new Object[]{});
+        }
+        return object;
+    }
+
+    /**
+     * 调用Setter方法, 仅匹配方法名。
+     * 支持多级，如：对象名.对象名.方法
+     */
+    public static void invokeSetter(Object obj, String propertyName, Object value) {
+        Object object = obj;
+        String[] names = StringUtils.split(propertyName, ".");
+        for (int i = 0; i < names.length; i++) {
+            if (i < names.length - 1) {
+                String getterMethodName = GETTER_PREFIX + StringUtils.capitalize(names[i]);
+                object = invokeMethod(object, getterMethodName, new Class[]{}, new Object[]{});
+            } else {
+                String setterMethodName = SETTER_PREFIX + StringUtils.capitalize(names[i]);
+                invokeMethodByName(object, setterMethodName, new Object[]{value});
+            }
+        }
+    }
+
+    /**
+     * 直接读取对象属性值, 无视private/protected修饰符, 不经过getter函数.
+     */
+    public static Object getFieldValue(final Object obj, final String fieldName) {
+        Field field = getAccessibleField(obj, fieldName);
+
+        if (field == null) {
+            throw new IllegalArgumentException("Could not find field [" + fieldName + "] on target [" + obj + "]");
+        }
+
+        Object result = null;
+        try {
+            result = field.get(obj);
+        } catch (IllegalAccessException e) {
+            logger.error("不可能抛出的异常{}", e.getMessage());
+        }
+        return result;
+    }
+
+    /**
+     * 直接设置对象属性值, 无视private/protected修饰符, 不经过setter函数.
+     */
+    public static void setFieldValue(final Object obj, final String fieldName, final Object value) {
+        Field field = getAccessibleField(obj, fieldName);
+
+        if (field == null) {
+            throw new IllegalArgumentException("Could not find field [" + fieldName + "] on target [" + obj + "]");
+        }
+
+        try {
+            field.set(obj, value);
+        } catch (IllegalAccessException e) {
+            logger.error("不可能抛出的异常:{}", e.getMessage());
+        }
+    }
+
+    /**
+     * 直接调用对象方法, 无视private/protected修饰符.
+     * 用于一次性调用的情况，否则应使用getAccessibleMethod()函数获得Method后反复调用.
+     * 同时匹配方法名+参数类型，
+     */
+    public static Object invokeMethod(final Object obj, final String methodName, final Class<?>[] parameterTypes,
+                                      final Object[] args) {
+        Method method = getAccessibleMethod(obj, methodName, parameterTypes);
+        if (method == null) {
+            throw new IllegalArgumentException("Could not find method [" + methodName + "] on target [" + obj + "]");
+        }
+
+        try {
+            return method.invoke(obj, args);
+        } catch (Exception e) {
+            throw convertReflectionExceptionToUnchecked(e);
+        }
+    }
+
+    /**
+     * 直接调用对象方法, 无视private/protected修饰符，
+     * 用于一次性调用的情况，否则应使用getAccessibleMethodByName()函数获得Method后反复调用.
+     * 只匹配函数名，如果有多个同名函数调用第一个。
+     */
+    public static Object invokeMethodByName(final Object obj, final String methodName, final Object[] args) {
+        Method method = getAccessibleMethodByName(obj, methodName);
+        if (method == null) {
+            throw new IllegalArgumentException("Could not find method [" + methodName + "] on target [" + obj + "]");
+        }
+
+        try {
+            return method.invoke(obj, args);
+        } catch (Exception e) {
+            throw convertReflectionExceptionToUnchecked(e);
+        }
+    }
+
+    /**
+     * 循环向上转型, 获取对象的DeclaredField, 并强制设置为可访问.
+     * <p>
+     * 如向上转型到Object仍无法找到, 返回null.
+     */
+    public static Field getAccessibleField(final Object obj, final String fieldName) {
+        Validate.notNull(obj, "object can't be null");
+        Validate.notBlank(fieldName, "fieldName can't be blank");
+        for (Class<?> superClass = obj.getClass(); superClass != Object.class; superClass = superClass.getSuperclass()) {
+            try {
+                Field field = superClass.getDeclaredField(fieldName);
+                makeAccessible(field);
+                return field;
+            } catch (NoSuchFieldException e) {//NOSONAR
+                // Field不在当前类定义,继续向上转型
+                continue;// new add
+            }
+        }
+        return null;
+    }
+
+    /**
+     * 循环向上转型, 获取对象的DeclaredMethod,并强制设置为可访问.
+     * 如向上转型到Object仍无法找到, 返回null.
+     * 匹配函数名+参数类型。
+     * <p>
+     * 用于方法需要被多次调用的情况. 先使用本函数先取得Method,然后调用Method.invoke(Object obj, Object... args)
+     */
+    public static Method getAccessibleMethod(final Object obj, final String methodName,
+                                             final Class<?>... parameterTypes) {
+        Validate.notNull(obj, "object can't be null");
+        Validate.notBlank(methodName, "methodName can't be blank");
+
+        for (Class<?> searchType = obj.getClass(); searchType != Object.class; searchType = searchType.getSuperclass()) {
+            try {
+                Method method = searchType.getDeclaredMethod(methodName, parameterTypes);
+                makeAccessible(method);
+                return method;
+            } catch (NoSuchMethodException e) {
+                // Method不在当前类定义,继续向上转型
+                continue;// new add
+            }
+        }
+        return null;
+    }
+
+    /**
+     * 循环向上转型, 获取对象的DeclaredMethod,并强制设置为可访问.
+     * 如向上转型到Object仍无法找到, 返回null.
+     * 只匹配函数名。
+     * <p>
+     * 用于方法需要被多次调用的情况. 先使用本函数先取得Method,然后调用Method.invoke(Object obj, Object... args)
+     */
+    public static Method getAccessibleMethodByName(final Object obj, final String methodName) {
+        Validate.notNull(obj, "object can't be null");
+        Validate.notBlank(methodName, "methodName can't be blank");
+
+        for (Class<?> searchType = obj.getClass(); searchType != Object.class; searchType = searchType.getSuperclass()) {
+            Method[] methods = searchType.getDeclaredMethods();
+            for (Method method : methods) {
+                if (method.getName().equals(methodName)) {
+                    makeAccessible(method);
+                    return method;
+                }
+            }
+        }
+        return null;
+    }
+
+    /**
+     * 改变private/protected的方法为public，尽量不调用实际改动的语句，避免JDK的SecurityManager抱怨。
+     */
+    public static void makeAccessible(Method method) {
+        if ((!Modifier.isPublic(method.getModifiers()) || !Modifier.isPublic(method.getDeclaringClass().getModifiers()))
+                && !method.isAccessible()) {
+            method.setAccessible(true);
+        }
+    }
+
+    /**
+     * 改变private/protected的成员变量为public，尽量不调用实际改动的语句，避免JDK的SecurityManager抱怨。
+     */
+    public static void makeAccessible(Field field) {
+        if ((!Modifier.isPublic(field.getModifiers()) || !Modifier.isPublic(field.getDeclaringClass().getModifiers()) || Modifier
+                .isFinal(field.getModifiers())) && !field.isAccessible()) {
+            field.setAccessible(true);
+        }
+    }
+
+    /**
+     * 通过反射, 获得Class定义中声明的泛型参数的类型, 注意泛型必须定义在父类处
+     * 如无法找到, 返回Object.class.
+     * eg.
+     * public UserDao extends HibernateDao<User>
+     *
+     * @param clazz The class to introspect
+     * @return the first generic declaration, or Object.class if cannot be determined
+     */
+    @SuppressWarnings("unchecked")
+    public static <T> Class<T> getClassGenricType(final Class clazz) {
+        return getClassGenricType(clazz, 0);
+    }
+
+    /**
+     * 通过反射, 获得Class定义中声明的父类的泛型参数的类型.
+     * 如无法找到, 返回Object.class.
+     * <p>
+     * 如public UserDao extends HibernateDao<User,Long>
+     *
+     * @param clazz clazz The class to introspect
+     * @param index the Index of the generic ddeclaration,start from 0.
+     * @return the index generic declaration, or Object.class if cannot be determined
+     */
+    public static Class getClassGenricType(final Class clazz, final int index) {
+
+        Type genType = clazz.getGenericSuperclass();
+
+        if (!(genType instanceof ParameterizedType)) {
+            logger.warn(clazz.getSimpleName() + "'s superclass not ParameterizedType");
+            return Object.class;
+        }
+
+        Type[] params = ((ParameterizedType) genType).getActualTypeArguments();
+
+        if (index >= params.length || index < 0) {
+            logger.warn("Index: " + index + ", Size of " + clazz.getSimpleName() + "'s Parameterized Type: "
+                    + params.length);
+            return Object.class;
+        }
+        if (!(params[index] instanceof Class)) {
+            logger.warn(clazz.getSimpleName() + " not set the actual class on superclass generic parameter");
+            return Object.class;
+        }
+
+        return (Class) params[index];
+    }
+
+    public static Class<?> getUserClass(Object instance) {
+        Assert.notNull(instance, "Instance must not be null");
+        Class clazz = instance.getClass();
+        if (clazz != null && clazz.getName().contains(CGLIB_CLASS_SEPARATOR)) {
+            Class<?> superClass = clazz.getSuperclass();
+            if (superClass != null && !Object.class.equals(superClass)) {
+                return superClass;
+            }
+        }
+        return clazz;
+
+    }
+
+    /**
+     * 将反射时的checked exception转换为unchecked exception.
+     */
+    public static RuntimeException convertReflectionExceptionToUnchecked(Exception e) {
+        if (e instanceof IllegalAccessException || e instanceof IllegalArgumentException
+                || e instanceof NoSuchMethodException) {
+            return new IllegalArgumentException(e);
+        } else if (e instanceof InvocationTargetException) {
+            return new RuntimeException(((InvocationTargetException) e).getTargetException());
+        } else if (e instanceof RuntimeException) {
+            return (RuntimeException) e;
+        }
+        return new RuntimeException("Unexpected Checked Exception.", e);
+    }
+}