package com.n_app.util;  
  
import java.lang.reflect.Constructor;  
import java.lang.reflect.Field;  
import java.lang.reflect.InvocationTargetException;  
import java.lang.reflect.Modifier;  
import java.util.Arrays;  
import java.util.Collection;  
import java.util.HashSet;  
import java.util.Map;  
import java.util.Set;  
  
/** 
 * 克隆工具类 
 * @author lujijiang@gmail.com 
 * 
 */  
public class Clone {  
    /** 
     * 无需进行复制的特殊类型数组 
     */  
    static Class[] needlessCloneClasses = new Class[]{String.class,Boolean.class,Character.class,Byte.class,Short.class,  
        Integer.class,Long.class,Float.class,Double.class,Void.class,Object.class,Class.class  
    };  
    /** 
     * 判断该类型对象是否无需复制 
     * @param c 指定类型 
     * @return 如果不需要复制则返回真，否则返回假 
     */  
    private static boolean isNeedlessClone(Class c){  
        if(c.isPrimitive()){//基本类型  
            return true;  
        }  
        for(Class tmp:needlessCloneClasses){//是否在无需复制类型数组里  
            if(c.equals(tmp)){  
                return true;  
            }  
        }  
        return false;  
    }  
      
    /** 
     * 尝试创建新对象 
     * @param c 原始对象 
     * @return 新的对象 
     * @throws IllegalAccessException 
     */  
    private static Object createObject(Object value) throws IllegalAccessException{  
            try {  
                return value.getClass().newInstance();  
            } catch (InstantiationException e) {  
                return null;  
            } catch (IllegalAccessException e) {  
                throw e;  
            }  
    }  
      
    /** 
     * 复制对象数据 
     * @param value 原始对象 
     * @param level 复制深度。小于0为无限深度，即将深入到最基本类型和Object类级别的数据复制； 
     * 大于0则按照其值复制到指定深度的数据，等于0则直接返回对象本身而不进行任何复制行为。 
     * @return 返回复制后的对象 
     * @throws IllegalAccessException 
     * @throws InstantiationException 
     * @throws InvocationTargetException 
     * @throws NoSuchMethodException 
     */  
    public static Object clone(Object value,int level) throws IllegalAccessException, InstantiationException, InvocationTargetException, NoSuchMethodException{  
        if(value==null){  
            return null;  
        }  
        if(level==0){  
            return value;  
        }  
        Class c = value.getClass();  
        if(isNeedlessClone(c)){  
            return value;  
        }  
        level--;  
        if(value instanceof Collection){//复制新的集合  
            Collection tmp = (Collection)c.newInstance();  
            for(Object v:(Collection)value){  
                tmp.add(clone(v,level));//深度复制  
            }  
            value = tmp;  
        }  
        else if(c.isArray()){//复制新的Array  
            //首先判断是否为基本数据类型  
            if(c.equals(int[].class)){  
                int[] old = (int[])value;  
                value = (int[])Arrays.copyOf(old, old.length);  
            }  
            else if(c.equals(short[].class)){  
                short[] old = (short[])value;  
                value = (short[])Arrays.copyOf(old, old.length);  
            }  
            else if(c.equals(char[].class)){  
                char[] old = (char[])value;  
                value = (char[])Arrays.copyOf(old, old.length);  
            }  
            else if(c.equals(float[].class)){  
                float[] old = (float[])value;  
                value = (float[])Arrays.copyOf(old, old.length);  
            }  
            else if(c.equals(double[].class)){  
                double[] old = (double[])value;  
                value = (double[])Arrays.copyOf(old, old.length);  
            }  
            else if(c.equals(long[].class)){  
                long[] old = (long[])value;  
                value = (long[])Arrays.copyOf(old, old.length);  
            }  
            else if(c.equals(boolean[].class)){  
                boolean[] old = (boolean[])value;  
                value = (boolean[])Arrays.copyOf(old, old.length);  
            }  
            else if(c.equals(byte[].class)){  
                byte[] old = (byte[])value;  
                value = (byte[])Arrays.copyOf(old, old.length);  
            }  
            else {  
                Object[] old = (Object[])value;  
                Object[] tmp = (Object[])Arrays.copyOf(old, old.length, old.getClass());  
                for(int i = 0;i<old.length;i++){  
                    tmp[i] = clone(old[i],level);  
                }  
                value = tmp;  
            }  
        }  
        else if(value instanceof Map){//复制新的MAP  
            Map tmp = (Map)c.newInstance();  
            Map org = (Map)value;  
            for(Object key:org.keySet()){  
                tmp.put(key, clone(org.get(key),level));//深度复制  
            }  
            value = tmp;  
        }  
        else {  
            Object tmp = createObject(value);  
            if(tmp==null){//无法创建新实例则返回对象本身，没有克隆  
                return value;  
            }  
            Set<Field> fields = new HashSet<Field>();  
            while(c!=null&&!c.equals(Object.class)){  
                fields.addAll(Arrays.asList(c.getDeclaredFields()));  
                c = c.getSuperclass();  
            }  
            for(Field field:fields){  
                if(!Modifier.isFinal(field.getModifiers())){//仅复制非final字段  
                    field.setAccessible(true);  
                    field.set(tmp, clone(field.get(value),level));//深度复制  
                }  
            }  
            value = tmp;  
        }  
        return value;  
    }  
      
    /** 
     * 浅表复制对象 
     * @param value 原始对象 
     * @return 复制后的对象，只复制一层 
     * @throws IllegalAccessException 
     * @throws InstantiationException 
     * @throws InvocationTargetException 
     * @throws NoSuchMethodException 
     */  
    public static Object clone(Object value) throws IllegalAccessException, InstantiationException, InvocationTargetException, NoSuchMethodException{  
        return clone(value,1);  
    }  
      
    /** 
     * 深度复制对象 
     * @param value 原始对象 
     * @return 复制后的对象 
     * @throws IllegalAccessException 
     * @throws InstantiationException 
     * @throws InvocationTargetException 
     * @throws NoSuchMethodException 
     */  
    public static Object deepClone(Object value) throws IllegalAccessException, InstantiationException, InvocationTargetException, NoSuchMethodException{  
        return clone(value,-1);  
    }  
}