package com.hg.ecommerce.model.support;
import java.io.Serializable;
import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.json.JSONArray;
import org.json.JSONObject;
import com.hg.ecommerce.util.Util;
/**
* 可以作为实体的公共父类，附加了很多便捷方法
* @author Li He
*
*/
public class EntityObject implements Serializable{
/**
*
*/
private static final long serialVersionUID = -8495226126373394030L;
private static final String GETTER_PREFIX = "get";
private static final String SETTER_PREFIX = "set";
private static final String IS_PREFIX = "is";
/**
* 根据字段名设置一个字段值， String to EntityObject，只支持Object
* @param fieldName
* @param value
* @return
*/
@SuppressWarnings("rawtypes")
public boolean setField(String fieldName, String value){
try{
MethodPair pair = getMethodPairByField(fieldName);
if(pair==null){
List<Field> fields = getEntityObjectFields();
if(fields==null||fields.size()==0){
return false;
}else{
for(Field field : fields){
Class fieldCls = field.getType();
MethodPair innerPair = getMethodPairByField(field.getName());
Object fieldValue = innerPair.getGetterMethod().invoke(this, (Object[])null);
if(fieldValue == null){
fieldValue = fieldCls.newInstance();
}
boolean result = ((EntityObject)fieldValue).setField(fieldName, value);
if(result){
innerPair.getSetterMethod().invoke(this, fieldValue);
return true;
}else{
continue;
}
}
}
return false;
}
Method setter = pair.getSetterMethod();
Field field = getClass().getDeclaredField(fieldName);
Class fieldCls = field.getType();
String typeName = fieldCls.getSimpleName();
//类型判断 int(Integer) double(Double) long(Long) boolean(Boolean) short(Short) byte(Byte)
if(typeName.equals("int")){
setter.invoke(this, Integer.valueOf(value));
}else if(typeName.equals("double")){
setter.invoke(this, Double.valueOf(value));
}else if(typeName.equals("boolean")){
setter.invoke(this, Boolean.valueOf(value));
}else if(typeName.equals("List")){
setter.invoke(this, value);
}else{
Object temp = fieldCls.newInstance();
if(temp instanceof Date){
setter.invoke(this, Util.stringToDate(value));
}else if(temp instanceof String){
setter.invoke(this, value);
}else{
return false;
}
}
return true;
}catch(Exception exception){
exception.printStackTrace();
return false;
}
}
/**
* 获取EntityObject子类的字段，其他字段忽略
* @return
*/
private List<Field> getEntityObjectFields(){
Field[] fields = getClass().getDeclaredFields();
List<Field> list = new ArrayList<Field>();
for(Field field : fields){
@SuppressWarnings("rawtypes")
Class cls = field.getType();
try{
Object object = cls.newInstance();
if(object instanceof EntityObject){
list.add(field);
}
}catch(Exception exception){
//exception.printStackTrace();
continue;
}
}
return list;
}
/**
* 根据field名称获取一个MethodPair对象
* @param fieldName
* @return
*/
private MethodPair getMethodPairByField(String fieldName){
try{
Field field = getClass().getDeclaredField(fieldName);
Method[] methods = getClass().getDeclaredMethods();
String methodAffix = field.getName().toUpperCase().charAt(0)+field.getName().substring(1); //将字段名转换为方法名的后缀
Method setter = null;
Method getter = null;
boolean hasSetter = false;
boolean hasGetter = false;
for(Method method : methods){
Pattern pattern = Pattern.compile("(get|set)"+methodAffix);
Matcher matcher = pattern.matcher(method.getName());
if(matcher.find()){
if(matcher.group(1).equals(GETTER_PREFIX)){
hasGetter = true;
getter = method;
if(hasSetter){
break;
}
}else if(matcher.group(1).equals(SETTER_PREFIX)){
hasSetter = true;
setter = method;
if(hasGetter){
break;
}
}
}
}
if(setter == null || getter == null){
return null;
}else{
MethodPair pair = new MethodPair();
pair.setSetterMethod(setter);
pair.setGetterMethod(getter);
return pair;
}
}catch(Exception exception){
return null;
}
}
/**
* 这个inner class保存一对getter与setter method
* @author Li He
*
*/
private class MethodPair {
private Method setterMethod;
private Method getterMethod;
public Method getSetterMethod() {
return setterMethod;
}
public void setSetterMethod(Method setterMethod) {
this.setterMethod = setterMethod;
}
public Method getGetterMethod() {
return getterMethod;
}
public void setGetterMethod(Method getterMethod) {
this.getterMethod = getterMethod;
}
}
/**
* 生成JSONObject，可以序列化为字符串
* @return JSONObject
*/
public JSONObject toJSON(){
try{
Method[] methods = getClass().getDeclaredMethods(); //获取声明的全部methods
JSONObject json = new JSONObject();
for(Method method : methods){
String fieldName = null;
/*
* 判断是否为getter method，如果为getter method，赋值fieldName
*/
if(method.getName().startsWith(GETTER_PREFIX)){
fieldName = Character.toLowerCase(method.getName().charAt(GETTER_PREFIX.length()))+method.getName().substring(GETTER_PREFIX.length()+1);
}else if(method.getName().startsWith(IS_PREFIX)){
fieldName = Character.toLowerCase(method.getName().charAt(IS_PREFIX.length()))+method.getName().substring(IS_PREFIX.length()+1);
}
/*
* fieldName不为空，此方法为getter method
*/
if(fieldName!=null){
Field field = getClass().getDeclaredField(fieldName); //获取Field对象
boolean ormField = false; //是否为orm框架关联注释字段
//必须排除@ManyToOne @ManyToMany @OneToMany的情况
Annotation[] annotations = field.getDeclaredAnnotations();
for(Annotation annotation : annotations){
String annotationName = annotation.annotationType().getSimpleName();
if(annotationName.equals("ManyToOne")||annotationName.equals("OneToMany")||annotationName.equals("ManyToMany")){
ormField = true;
break;
}
}
if(!ormField){
Object object = method.invoke(this, (Object[])null);
json.put(fieldName, getJsonObject(object));
}
}
}
return json;
}catch(Exception exception){
//System.err.println("Error Occurs!");
exception.printStackTrace();
return null;
}
}
/**
* 递归获取可以put到JSONObject中的对象
* @param object
* @return
*/
@SuppressWarnings("rawtypes")
private Object getJsonObject(Object object){
if(object==null){
return null;
}
if(object instanceof EntityObject){ //字段对象为EntityObject
object = ((EntityObject)object).toJSON();
}else if(object instanceof Date){ //字段对象为Date
object = Util.dateToString((Date)object);
}else if(object instanceof Map){
JSONObject jsonObject = new JSONObject();
for(Object obj : ((Map)object).entrySet()){
Entry entry = (Entry)obj;
//如果为map，必须保证key为String
jsonObject.put(entry.getKey().toString(), getJsonObject(entry.getValue()));
}
object = jsonObject;
}else if(object instanceof Collection){
JSONArray jsonArray = new JSONArray();
for(Object obj : (Collection)object){
jsonArray.put(getJsonObject(obj));
}
object = jsonArray;
}
return object;
}
}