使用apache.commons.betwixt實現XML與Java對象互轉

##關於betwixt

##如何引用

在maven項目中添加如下依賴

<dependency>
<groupId>commons-betwixt</groupId>
<artifactId>commons-betwixt</artifactId>
<version>0.8</version>
</dependency>

##注意事項 轉化過程對 大小寫是敏感的，

例如 XML中的結點名稱是大寫的，而Java類中的成員變量是小寫的。那麼轉換將不會成功，獲得的結點值是空的。

##核心代碼

###建立一個測試對象

package com.icim.entity;

public class TestObj {
    private String name;
    private Integer age;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    /**
     * 必須有一個空的構造方法，不然會報錯
     */
    public TestObj() {

    }

    public TestObj(String name, Integer age) {
        super();
        this.name = name;
        this.age = age;
    }

    @Override
    public String toString() {
        return "TestObj [name=" + name + ", age=" + age + "]";
    }

}

###轉換對象

package com.icim.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.StringReader;
import java.io.StringWriter;
import java.io.UnsupportedEncodingException;

import org.apache.commons.betwixt.io.BeanReader;
import org.apache.commons.betwixt.io.BeanWriter;
import org.apache.log4j.Logger;

import com.icim.entity.TestObj;

public class XmlParseUtil {

    
    private static final Logger logger = Logger.getLogger(XmlParseUtil.class);

    private static final String XML_ROOT_NODE_NAME = "TRANSACTION";

    public static final String XML_HEADER = "<?xml version='1.0' encoding='UTF-8' ?>";

    /**
     * 將XML字符串 轉換成 對象
     * @param strInMsg : XML內容
     * @param clazz 
     * @return
     */
    public static Object inStr2Obj(String strInMsg, @SuppressWarnings("rawtypes") Class clazz) {
        BeanReader beanReader = new BeanReader();
        Object parse = null;

        StringReader xmlReader = new StringReader(strInMsg);

        beanReader.getXMLIntrospector().getConfiguration().setAttributesForPrimitives(false);
        beanReader.getBindingConfiguration().setMapIDs(false);

        try {
            beanReader.registerBeanClass(XML_ROOT_NODE_NAME, clazz);
            parse = beanReader.parse(xmlReader);
        } catch (Exception ex) {
            logger.error(ex.toString());
        }

        return parse;
    }
    /**
     * 將 對象 轉換成 XML字符串
     * @param inObj
     * @return
     */
    public static String obj2Str(Object inObj) {
        StringWriter sw = new StringWriter();
        BeanWriter beanWriter = new BeanWriter(sw);

        sw.write(XML_HEADER);
        try {
            beanWriter.setEndOfLine("");
            beanWriter.getBindingConfiguration().setMapIDs(false);
            beanWriter.getXMLIntrospector().getConfiguration().setAttributesForPrimitives(false);
            beanWriter.write(XML_ROOT_NODE_NAME, inObj);
        } catch (Exception e) {
            logger.error(e.toString());
        }

        return sw.toString();
    }
    
    /**
     * 將XML文件轉換成 對象
     * @param fileName
     * @param clazz
     * @return
     */
    public static Object file2Object(String fileName, Class clazz) {
        String fileContent = file2String(fileName);
        return inStr2Obj(fileContent, clazz);
    }

    /**
     * 將XML文件轉換成 對象
     * @param fileName
     * @param clazz
     * @return
     */
    public static Object file2Object(File file, Class clazz) {
        String fileContent = file2tring(file);
        return inStr2Obj(fileContent, clazz);
    }

    /**
     * 讀取文件所有內容
     * @param fileName
     * @return
     */
    private static String file2String(String fileName) {
        File file = new File(fileName);
        return file2tring(file);
    }
    
    /**
     * 讀取文件所有內容
     * @param file
     * @return
     */
    private static String file2tring(File file) {
        String encoding = "ISO-8859-1";
        Long filelength = file.length();
        byte[] filecontent = new byte[filelength.intValue()];
        try {
            FileInputStream in = new FileInputStream(file);
            in.read(filecontent);
            in.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        try {
            return new String(filecontent, encoding);
        } catch (UnsupportedEncodingException e) {
            System.err.println("The OS does not support " + encoding);
            e.printStackTrace();
            return null;
        }
    }
    
   
    //測試方法
    public static void main(String[] args) {
        TestObj obj = new TestObj("xiaoming", 18);
        
        String xmlString = XmlParseUtil.obj2Str(obj);
        System.out.println(xmlString);
        
        TestObj obj2 = (TestObj) XmlParseUtil.inStr2Obj(xmlString, TestObj.class);
        
        System.out.println(obj2);
        
    }

}

輸出結果

<?xml version='1.0' encoding='UTF-8' ?><TRANSACTION><age>18</age><name>xiaoming</name></TRANSACTION>
TestObj [name=xiaoming, age=18]