package com.zuidaima.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 www.zuidaima.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);
}
}
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public static void permutation(int[] src, int m) {
if (m == src.length) {
if (src.length > 3 && src[2] != 4) {
boolean bPrint = true;
for (int i = 0; i < src.length - 1; i++) {
if ((src[i] == 3 && src[i + 1] == 5)
|| (src[i] == 5 && src[i + 1] == 3)) {
bPrint = false;
}
}
if (bPrint)
print(src);
}
} else {
for (int i = m; i < src.length; i++) {
swap(src, m, i);
permutation(src, m + 1);
swap(src, m, i);
}
}
}
public static void print(int[] src) {
for (int i = 0; i < src.length; i++)
System.out.print(src[i]);
System.out.println();
}
private static void swap(int[] src, int m, int i) {
int t = src[m];
src[m] = src[i];
src[i] = t;
}
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