package com.taoyuan.entity.custom;/*** @ClassName: Student* @Description: TODO Student实体类设计* @author: Han* @date: 2016-3-31 下午4:54:04*/
public class Student {private int id;private String name;public int getId() {return id;}public void setId(int id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}@Overridepublic String toString() {return "this student`s id is " + this.id + " and name is " + this.name;}
}

package com.taoyuan.entity.custom;import java.util.List;/*** @ClassName: Class* @Description: TODO Class班级实体类设计* @author: Han* @date: 2016-3-31 下午4:58:21*/
public class Class {private int id;private String className;private List<Student> student;public int getId() {return id;}public void setId(int id) {this.id = id;}public String getClassName() {return className;}public void setClassName(String className) {this.className = className;}public List<Student> getStudents() {return student;}public void setStudents(List<Student> student) {this.student = student;}@Overridepublic String toString() {return "This class`s id is " + this.id + " and name is " + this.className+ "\t\nit`s students are " + this.student;}
}

<?xml version="1.0" encoding="UTF-8"?>
<Entity><Class classPath="com.taoyuan.entity.custom.Class"><Int name="id">1</Int><String name="className">软件工程</String><Student name="student" type="list"><!-- Student数组 --><Student classPath="com.taoyuan.entity.custom.Student"><Int name="id">1</Int><String name="name">李明</String></Student><Student  classPath="com.taoyuan.entity.custom.Student"><Int name="id">2</Int><String name="name">狗蛋</String></Student></Student></Class>
</Entity>

package com.taoyuan.utils;import java.io.File;
import java.io.FileNotFoundException;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;/*** @ClassName: XMLUtil* @Description: TODO XML工具类* @author: Han* @date: 2016-3-22 下午3:09:03*/
public class XMLUtil {/*** @Title: toEntity* @Description: TODO 将XML文件转换为一个entity* @param xmlPath* @return* @throws Exception* @return: Object*/public static Object toEntity(String xmlPath) throws Exception{//初始化，将XML文件读入内存，生成DocumentDocument _document = init(xmlPath);//获取根目录节点Element _rootEle = _document.getRootElement();String _rootName = "";if(_rootEle != null){//根目录节点名字_rootName = _rootEle.getName();}if(!_rootName.equals("Entity")){throw new Exception("请确认根节点名字是否为Entity");}List<Element> elements = _rootEle.elements();//在Entity节点中无子节点if(elements.size() == 0){return null;}return getEntity(elements.get(0));}/*** 获取根据节点Element获取对应的Entity* @param element* @return* @throws ClassNotFoundException* @throws InstantiationException* @throws IllegalAccessException*/@SuppressWarnings("rawtypes")private static Object getEntity(Element element)throws ClassNotFoundException, InstantiationException,IllegalAccessException {//获取classPathString _classPath = element.attributeValue("classPath");//获取Class的字节码文件Class _clazz = Class.forName(_classPath);//根据字节码文件进行实例化Object _object = _clazz.newInstance();Field[] _fields = _clazz.getDeclaredFields();setMember(_object, element, _fields);return _object;}/*** 设置成员变量* @param object* @param element* @param fields 成员变量数组*/private static void setMember(Object object, Element element, Field[] fields) {//获取当前Element获得的子节点迭代器Iterator<Element> _elements = element.elementIterator();while(_elements.hasNext()){Element _childElement = _elements.next();//当前正在设置的成员变量Field _field = null;//获取变量类型String _type = _childElement.getName();//获取变量名String _name = _childElement.attributeValue("name");//获取变量值String _value = _childElement.getTextTrim();//找到当前正在设置的成员变量for(int i = 0;i < fields.length;i ++ ){if(fields[i].getName().equals(_name)){_field = fields[i];break;}}if(_field == null){throw new RuntimeException("没找到该成员变量" + _name);}//此时可以访问私有成员变量_field.setAccessible(true);if(!setBaseTypeMember(object, _field, _type, _value)){//当前成员变量不是基本类型,则为引用类型成员变量
                setReferenceTypeMember(_childElement, object,  _field);}}}/*** 设置引用类型成员变量* @param element* @param object* @param field*/@SuppressWarnings({ "rawtypes", "unchecked" })private static void setReferenceTypeMember(Element element, Object object,  Field field) {try {//若为list，则表示当前元素为一个list集合String _memberType = element.attributeValue("type");if(_memberType.equals("list")){List _list = new ArrayList();Iterator<Element> _iterator = element.elementIterator();while(_iterator.hasNext()){Element _childEle = _iterator.next();//递归获取该元素，并加入集合中Object _entity = getEntity(_childEle);_list.add(_entity);}field.set(object, _list);return;}//单元素的引用类型Object _entity = getEntity(element);field.set(object, _entity);} catch (Exception e) {throw new RuntimeException(e);}}/*** 设置基本类型成员变量* @param object* @param field* @param type* @param value* @return*/private static boolean setBaseTypeMember(Object object, Field field,String type, String value) {try {if(type.equals("Int")){//int型成员变量
                field.setInt(object, Integer.parseInt(value));}else if(type.equals("Double")){//double型成员变量
                field.setDouble(object, Double.parseDouble(value));}else if(type.equals("Float")){//float型成员变量
                field.setFloat(object, Float.parseFloat(value));}else if(type.equals("Long")){//long型成员变量
                field.setLong(object, Long.parseLong(value));}else if(type.equals("Char")){//char型成员变量field.setChar(object, value.charAt(0));}else if(type.equals("String")){//string型成员变量
                field.set(object, value);}else{return false;}} catch (Exception e) {throw new RuntimeException(e);}return true;}/*** @Title: init* @Description: TODO 初始化，将XML读入内存* @param xmlPath* @return Document节点* @throws FileNotFoundException* @return: Document*/private static Document init(String xmlPath) throws FileNotFoundException {//获取XML文件路径.是根据当前classPath去寻找，例如文件a.xml是放在根目录下，则需要输入的路径便是a.xml//还有另外一种方法是通过class.getResource("/" + xmlPath)效果是一样的//关于java中的路径问题还是没有搞得很清楚，下来还需要多看String _filePath = XMLUtil.class.getClassLoader().getResource(xmlPath).getPath();File _file = new File(_filePath);//如果文件存在if(_file.exists()){//利用dom4j返回该XML的documentSAXReader _reader = new SAXReader();try {Document _document = _reader.read(_file);return _document;} catch (DocumentException e) {e.printStackTrace();}}else{throw new FileNotFoundException("您输入的XML文件地址未查到");}return null;}}

    @Testpublic void testXMLUtil() throws Exception{System.out.println(XMLUtil.toEntity("Class.xml"));}