Java 对象和xml转换工具类

package com.mcp.util;

import org.apache.commons.lang3.StringUtils;

import java.io.StringReader;
import java.io.StringWriter;
import java.util.Collection;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.annotation.XmlAnyElement;
import javax.xml.namespace.QName;

/**
 * Created by shiqm on 2016-05-01.
 */
public class JaxbUtil {

    // 多线程安全的Context.
    private JAXBContext jaxbContext;

    /**
     * @param types
     *            所有需要序列化的Root对象的类型.
     */
    public JaxbUtil(Class<?>... types) {
        try {
            jaxbContext = JAXBContext.newInstance(types);
        } catch (JAXBException e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * Java Object->Xml.
     */
    public String toXml(Object root, String encoding) {
        try {
            StringWriter writer = new StringWriter();
            createMarshaller(encoding).marshal(root, writer);
            return writer.toString();
        } catch (JAXBException e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * Java Object->Xml, 特别支持对Root Element是Collection的情形.
     */
    @SuppressWarnings("unchecked")
    public String toXml(Collection root, String rootName, String encoding) {
        try {
            CollectionWrapper wrapper = new CollectionWrapper();
            wrapper.collection = root;

            JAXBElement<CollectionWrapper> wrapperElement = new JAXBElement<CollectionWrapper>(
                    new QName(rootName), CollectionWrapper.class, wrapper);

            StringWriter writer = new StringWriter();
            createMarshaller(encoding).marshal(wrapperElement, writer);

            return writer.toString();
        } catch (JAXBException e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * Xml->Java Object.
     */
    @SuppressWarnings("unchecked")
    public <T> T fromXml(String xml) {
        try {
            StringReader reader = new StringReader(xml);
            return (T) createUnmarshaller().unmarshal(reader);
        } catch (JAXBException e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * Xml->Java Object, 支持大小写敏感或不敏感.
     */
    @SuppressWarnings("unchecked")
    public <T> T fromXml(String xml, boolean caseSensitive) {
        try {
            String fromXml = xml;
            if (!caseSensitive)
                fromXml = xml.toLowerCase();
            StringReader reader = new StringReader(fromXml);
            return (T) createUnmarshaller().unmarshal(reader);
        } catch (JAXBException e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * 创建Marshaller, 设定encoding(可为Null).
     */
    public Marshaller createMarshaller(String encoding) {
        try {
            Marshaller marshaller = jaxbContext.createMarshaller();

            marshaller.setProperty(Marshaller.JAXB_ENCODING, "UTF-8");// //编码格式
            marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.FALSE);// 是否格式化生成的xml串
            marshaller.setProperty(Marshaller.JAXB_FRAGMENT, Boolean.FALSE);// 是否省略xm头声明信息

            if (StringUtils.isNotBlank(encoding)) {
                marshaller.setProperty(Marshaller.JAXB_ENCODING, encoding);
            }
            return marshaller;
        } catch (JAXBException e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * 创建UnMarshaller.
     */
    public Unmarshaller createUnmarshaller() {
        try {
            return jaxbContext.createUnmarshaller();
        } catch (JAXBException e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * 封装Root Element 是 Collection的情况.
     */
    public static class CollectionWrapper {
        @SuppressWarnings("unchecked")
        @XmlAnyElement
        protected Collection collection;
    }
}

/**
 * Created by shiqm on 2016-04-29.
 */
public class XmlUtil {

    public static String toXML(Object obj) {
        try {
            JaxbUtil requestBinder = new JaxbUtil(obj.getClass());
            return requestBinder.toXml(obj, "utf-8");
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    @SuppressWarnings("unchecked")
    public static <T> T fromXML(String xml, Class<T> valueType) {
        try {
            JaxbUtil requestBinder = new JaxbUtil(valueType);
            return (T) requestBinder.fromXml(xml);
        } catch (Exception e) {
            throw new RuntimeException(e.getMessage());
        }
    }
}

Demo

这里以一个继承来展示，里边包含了普通熟悉和集合的转化，当然更可以不用继承。这里默认get和set方法来组织xml，没有方法的属性使用注解来组织xml。当然还可以不默认get和set方法,用@XmlAccessorType(XmlAccessType.FIELD) 

package com.mcp.bean.yeepay;


import com.mcp.cons.YeePayConstants;

import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlElement;

/**
 * Created by shiqm on 2016-04-29.
 */
public class Request {

    @XmlAttribute
    protected String platformNo = YeePayConstants.Config.MER_CODE;
    @XmlElement
    protected String notifyUrl = YeePayConstants.NOTITY_Url;
    @XmlElement
    protected String callbackUrl = YeePayConstants.CALLBACK_URL;
    private String platformUserNo;
    private String requestNo;



    public String getPlatformUserNo() {
        return platformUserNo;
    }

    public void setPlatformUserNo(String platformUserNo) {
        this.platformUserNo = platformUserNo;
    }

    public String getRequestNo() {
        return requestNo;
    }

    public void setRequestNo(String requestNo) {
        this.requestNo = requestNo;
    }

}

package com.mcp.bean.yeepay;


import javax.xml.bind.annotation.*;
import java.util.List;

/**
 * Created by shiqm on 2016-05-01.
 */
@XmlRootElement(name = "request")
public class CpTransactionParam extends Request {

    private String userType;
    private String bizType;

    private List<Property> properties;

    private List<Detail> details;

    public CpTransactionParam() {
    }

    public String getUserType() {
        return userType;
    }

    public void setUserType(String userType) {
        this.userType = userType;
    }

    public String getBizType() {
        return bizType;
    }

    public void setBizType(String bizType) {
        this.bizType = bizType;
    }

    @XmlElementWrapper(name = "extend")
    @XmlElement(name = "property")
    public List<Property> getProperties() {
        return properties;
    }

    public void setProperties(List<Property> properties) {
        this.properties = properties;
    }

    @XmlElementWrapper(name = "details")
    @XmlElement(name = "detail")
    public List<Detail> getDetails() {
        return details;
    }

    public void setDetails(List<Detail> details) {
        this.details = details;
    }
}