基于dom4j的xml映射实体的工具类(java)

工具是基于dom4j，使用反射使实体属性与xml的标签关联，目前兼容List，Map后续更新兼容。

历史更新：

发布-2019-6-22

增加注解@XmlAttr关联实体与xml(解决实体名与xml属性名不相同的情况)-2019-7-12

背景故事：这是个大哥与小弟的团队关系

xml文件

大哥

70

小弟1

50

小小弟1-1

45

小小弟1-2

45

小弟2

51

小小弟2-1

50

小小弟2-2

50

实体

1)大哥的实体

import java.util.List;

public class BigBro {

@XmlAttr("name")

private String name;

@XmlAttr("power")

private String power;

@XmlAttr("brolist")

private List brolist;

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public String getPower() {

return power;

}

public void setPower(String power) {

this.power = power;

}

public List getBrolist() {

return brolist;

}

public void setBrolist(List brolist) {

this.brolist = brolist;

}

}

2)小弟的实体

import java.util.List;

public class Bro {

@XmlAttr("name")

private String name;

@XmlAttr("power")

private String power;

@XmlAttr("")

private List littlebrolist;

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public String getPower() {

return power;

}

public void setPower(String power) {

this.power = power;

}

public List getLittlebrolist() {

return littlebrolist;

}

public void setLittlebrolist(List littlebrolist) {

this.littlebrolist = littlebrolist;

}

}

XmlReader代码

import Annotation.XmlAttr;

import Annotation.XmlAttrImplicit;

import entity.RspPerson;

import org.dom4j.Document;

import org.dom4j.DocumentException;

import org.dom4j.Element;

import org.dom4j.io.SAXReader;

import java.beans.IntrospectionException;

import java.beans.PropertyDescriptor;

import java.io.StringReader;

import java.lang.reflect.*;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.Iterator;

import java.util.List;

public class XmlReader {

public XmlReader() {

}

/**

* 映射xml到实体

* @param clazz

* @param xmlStr

* @param

* @return

*/

public T parseToEntity(Class clazz, String xmlStr) {

SAXReader reader = new SAXReader();

reader.setEncoding("GBK");

Document doc;

T obj = null;

try {

obj = clazz.getDeclaredConstructor().newInstance();

doc = reader.read(new StringReader(xmlStr));

Element root = doc.getRootElement();

handleNode(root, obj);

} catch (DocumentException e) {

e.printStackTrace();

} catch (InstantiationException e) {

e.printStackTrace();

} catch (InvocationTargetException e) {

e.printStackTrace();

} catch (NoSuchMethodException e) {

e.printStackTrace();

} catch (IllegalAccessException e) {

e.printStackTrace();

}

return obj;

}

/**

* 处理节点

* @param element

* @param t

* @param

*/

public void handleNode(Element element, T t) {

for (Iterator it = element.elementIterator(); it.hasNext();) {

Element child = it.next();

Field field = null;

try {

field = getFieldByAttrName(child.getName(), t);

if (field == null) {

return ;

}

PropertyDescriptor descriptor = new PropertyDescriptor(field.getName(), t.getClass());

Class> clazz = Class.forName(field.getType().getTypeName());

Object childObject = null;

if (descriptor.getPropertyType().getTypeName().equals("java.util.List")) {

childObject = Proxy.newProxyInstance(RspPerson.class.getClassLoader(), new Class[] {clazz}, new MyHandler());

} else {

childObject = Class.forName(field.getType().getTypeName()).getDeclaredConstructor().newInstance();

}

Method setMethod = descriptor.getWriteMethod(); //获得set方法

Type type = field.getGenericType();

if (type instanceof ParameterizedType) {

//带参数类型的属性

ParameterizedType pt = (ParameterizedType)type; //获取参数类型

// System.out.println("带参数" + type.getTypeName());

String paramClassName = pt.getActualTypeArguments()[0].getTypeName(); //获取实体属性的参数类型，如List的A

if (childObject instanceof List) {

ArrayList childList = new ArrayList();

Iterator childIterator = child.elementIterator();

while (childIterator.hasNext()) {

Element sonOfElement = childIterator.next();

System.out.println(sonOfElement.getName());

Object paramObject = Class.forName(paramClassName).getDeclaredConstructor().newInstance();

childList.add(paramObject);

handleNode(sonOfElement, paramObject);

}

setMethod.invoke(t, childList);

} else if (childObject instanceof HashMap){

//HashMap类型属性...

}

} else {

//不带参数类型的属性

// System.out.println("非带参数" + type.getTypeName());

setMethod.invoke(t, child.getData());

}

} catch (SecurityException e) {

e.printStackTrace();

} catch (InstantiationException e) {

e.printStackTrace();

} catch (IllegalAccessException e) {

e.printStackTrace();

} catch (ClassNotFoundException e) {

e.printStackTrace();

} catch (NoSuchMethodException e) {

e.printStackTrace();

} catch (InvocationTargetException e) {

e.printStackTrace();

} catch (IntrospectionException e) {

e.printStackTrace();

}

}

}

private Field getFieldByAttrName(String xmlAttrName, T t) {

for (Field f : t.getClass().getDeclaredFields()) {

if (f.isAnnotationPresent(XmlAttr.class)) {

if(f.getAnnotation(XmlAttr.class).value().equals(xmlAttrName)){

return f;

}

} else if (f.isAnnotationPresent(XmlAttrImplicit.class)) {

if (f.getAnnotation(XmlAttrImplicit.class).value().equals(xmlAttrName)){

return f;

}

}

}

return null;

}

}

-MyHandler代码

import java.lang.reflect.InvocationHandler;

import java.lang.reflect.Method;

import java.util.List;

class MyHandler implements InvocationHandler {

@Override

public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {

return null;

}

}

-@XmlAttr 注解

package Annotation;

import java.lang.annotation.ElementType;

import java.lang.annotation.Retention;

import java.lang.annotation.RetentionPolicy;

import java.lang.annotation.Target;

/**

* 普通属性，基本数据类型的包装类

*/

@Retention(RetentionPolicy.RUNTIME)

@Target(ElementType.FIELD)

public @interface XmlAttr {

String value() default "";

}

-@XmlAttrImplicit注解

package Annotation;

import java.lang.annotation.ElementType;

import java.lang.annotation.Retention;

import java.lang.annotation.RetentionPolicy;

import java.lang.annotation.Target;

/**

* 属性为集合接口List,Map等类型

*/

@Retention(RetentionPolicy.RUNTIME)

@Target(ElementType.FIELD)

public @interface XmlAttrImplicit {

String value() default "";

}

结果