Jibx 处理XML

前面有介绍过json-lib这个框架，在线博文：http://www.cnblogs.com/hoojo/archive/2011/04/21/2023805.html

以及Jackson这个框架，在线博文：http://www.cnblogs.com/hoojo/archive/2011/04/22/2024628.html

它们都可以完成Java对象到XML的转换，但是还不是那么的完善。

还有XStream对JSON及XML的支持，它可以对JSON或XML的完美转换。在线博文：

http://www.cnblogs.com/hoojo/archive/2011/04/22/2025197.html

以及介绍Castor来完成Java对象到xml的相互转换。在线博文：http://www.cnblogs.com/hoojo/archive/2011/04/25/2026819.html

Jaxb2完成xml的转换，在线博文：http://www.cnblogs.com/hoojo/archive/2011/04/26/2029011.html

Jibx对Java对象的转换相对要负责些，它不仅需要配置xml还且还要生成相应的jar文件，已经xsd文件。下面我们就来慢慢看看Jibx转换Java到XML是如何完成的。

一、 准备工作

1、 准备资源

a) 官方示例：http://jibx.sourceforge.net/fromcode/bindgen-examples.html

http://www.java2s.com/Open-Source/Java/XML/JiBX/tutorial/Catalogtutorial.htm

b) Jar下载：http://sourceforge.net/projects/jibx/files/

c) 依赖jar包如下：

2、 程序准备代码

package com.hoo.test;

import java.io.IOException;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.jibx.runtime.BindingDirectory;
import org.jibx.runtime.IBindingFactory;
import org.jibx.runtime.IMarshallingContext;
import org.jibx.runtime.IUnmarshallingContext;
import org.jibx.runtime.JiBXException;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import com.hoo.entity.Account;
import com.hoo.entity.AccountArray;
import com.hoo.entity.Birthday;
import com.hoo.entity.ListBean;
import com.hoo.entity.MapBean;

/**
 * <b>function:</b> Jibx转换Java到XML
 * @author hoojo
 * @createDate 2011-4-25 下午06:47:33
 * @file JibxTest.java
 * @package com.hoo.test
 * @project WebHttpUtils
 * @blog http://blog.csdn.net/IBM_hoojo
 * @email hoojo_@126.com
 * @version 1.0
 */
public class JibxTest {
    private IBindingFactory factory = null;

    private StringWriter writer = null;
    private StringReader reader = null;

    private Account bean = null;

    @Before
    public void init() {
        bean = new Account();
        bean.setAddress("北京");
        bean.setEmail("email");
        bean.setId(1);
        bean.setName("jack");
        Birthday day = new Birthday();
        day.setBirthday("2010-11-22");
        bean.setBirthday(day);

        try {
            factory = BindingDirectory.getFactory(Account.class);
        } catch (JiBXException e) {
            e.printStackTrace();
        }
    }

    @After
    public void destory() {
        bean = null;
        try {
            if (writer != null) {
                writer.flush();
                writer.close();
            }
            if (reader != null) {
                reader.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        System.gc();
    }

    public void fail(Object o) {
        System.out.println(o);
    }

    public void failRed(Object o) {
        System.err.println(o);
    }
}

IBindingFactory是一个工厂接口，通过BindingDirectory的getFactory工厂方法可以获得某个对象。然后通过这个工程可以获得转换xml文档的上下文。

二、 转换Java到XML、转换XML到Java

1、 转换JavaEntity对象

a) 首先看看Account、Birthday的代码

package com.hoo.entity;

public class Account {
    private int id;
    private String name;
    private String email;
    private String address;
    private Birthday birthday;
    //getter、setter

    @Override
    public String toString() {
        return this.id + "#" + this.name + "#" + this.email + "#" + this.address + "#" + this.birthday;
    }
}

Birthday

package com.hoo.entity;

public class Birthday {
    private String birthday;

    public Birthday(String birthday) {
        super();
        this.birthday = birthday;
    }
    //getter、setter
    public Birthday() {}

    @Override
    public String toString() {
        return this.birthday;
    }
}

b) 程序代码

@Test
public void bean2XML() {
    try {
        writer = new StringWriter();
        // marshal 编组
        IMarshallingContext mctx = factory.createMarshallingContext();
        mctx.setIndent(2);
        mctx.marshalDocument(bean, "UTF-8", null, writer);
        fail(writer);

        reader = new StringReader(writer.toString());
        //unmarshal 解组
        IUnmarshallingContext uctx = factory.createUnmarshallingContext();
        Account acc = (Account) uctx.unmarshalDocument(reader, null);
        fail(acc);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

这样还不够，复杂的东西还在后面。Jibx转换XML文档还要经过一系列复杂的程序。

c) 首先，要写bind.xml和schema。不过还好，官方有提高工具类可以用。

org.jibx.binding.generator.BindGen或org.jibx.binding.BindingGenerator这两个类都可以，用法如下：

首先用dos进入当前工程目录，然后执行命令：E:\Study\WebHttpUtils>java -cp bin;lib/jibx-tools.jar;lib/log4j-1.2.16.jar org.jibx.binding.generator.BindGen -b bind.xml com.hoo.entity.Account

上面的java 是运行某个程序 –cp是依赖的classpath路径的jar、zip等文件，-b 是输出文件名称，是BindGen类的参数。这样会在当前工程目录中生成bind.xml和entity.xsd文件。先看看这2个文件

bind.xml

<?xml version="1.0" encoding="UTF-8"?>
<binding value-style="attribute">
  <mapping class="com.hoo.entity.Account" name="account">
    <value name="id" field="id"/>
    <value style="element" name="name" field="name" usage="optional"/>
    <value style="element" name="email" field="email" usage="optional"/>
    <value style="element" name="address" field="address" usage="optional"/>
    <structure field="birthday" usage="optional" name="birthday">
      <value style="element" name="birthday" field="birthday" usage="optional"/>
    </structure>
  </mapping>
</binding>

entity.xsd文件

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:tns="http://hoo.com/entity"
elementFormDefault="qualified" targetNamespace="http://hoo.com/entity">
  <xs:element type="tns:account" name="account"/>
  <xs:complexType name="account">
    <xs:sequence>
      <xs:element type="xs:string" name="name" minOccurs="0"/>
      <xs:element type="xs:string" name="email" minOccurs="0"/>
      <xs:element type="xs:string" name="address" minOccurs="0"/>
      <xs:element name="birthday" minOccurs="0">
        <xs:complexType>
          <xs:sequence>
            <xs:element type="xs:string" name="birthday" minOccurs="0"/>
          </xs:sequence>
        </xs:complexType>
      </xs:element>
    </xs:sequence>
    <xs:attribute type="xs:int" use="required" name="id"/>
  </xs:complexType>
</xs:schema>

上面最重要的就是bind.xml文件了，下面编译的时候需要这个文件。Xsd文件可以根据这个文件的内容生成Java的Entity类代码。

执行完命令后，没有错误就可以运行下面一段命令了。运行命令：

E:\Study\WebHttpUtils>java -cp bin;lib/jibx-bind.jar org.jibx.binding.Compile -v bind.xml

-v是绑定文件的名称

运行后，有如下结果：

d) 然后你就可以运行上面的Java的Junit测试程序了，运行后结果如下：

<?xml version="1.0" encoding="UTF-8"?>
<account xmlns="http://hoo.com/entity" id="1">
  <name>jack</name>
  <email>email</email>
  <address>北京</address>
  <birthday>
    <birthday>2010-11-22</birthday>
  </birthday>
</account>
1#jack#email#北京#2010-11-22

你还可以用命令来查看某个已经生成bind、schema文件的信息，如：

java -cp bin;lib/jibx-run.jar org.jibx.runtime.PrintInfo -c com.hoo.entity.Account

结果如下：

e) 注意，有时候会出现异常信息，如：java.lang.NoSuchFieldException: JiBX_bindingXXXX就要重复下面的命令就可以了。

java -cp bin;lib/jibx-bind.jar org.jibx.binding.Compile -v bind.xml

2、 转换带List集合属性的JavaBean

a) 程序代码

@Test
public void listBean2XML() {
    try {
        ListBean listBean = new ListBean();
        List<Account> list = new ArrayList<Account>();
        list.add(bean);
        bean = new Account();
        bean.setAddress("china");
        bean.setEmail("tom@125.com");
        bean.setId(2);
        bean.setName("tom");
        Birthday day = new Birthday("2010-11-22");
        bean.setBirthday(day);

        list.add(bean);
        listBean.setList(list);


        writer = new StringWriter();
        factory = BindingDirectory.getFactory(ListBean.class);
        // marshal 编组
        IMarshallingContext mctx = factory.createMarshallingContext();
        mctx.setIndent(2);
        mctx.marshalDocument(listBean, "UTF-8", null, writer);
        fail(writer);

        reader = new StringReader(writer.toString());
        //unmarshal 解组
        IUnmarshallingContext uctx = factory.createUnmarshallingContext();
        listBean = (ListBean) uctx.unmarshalDocument(reader, null);

        fail(listBean.getList().get(0));
        fail(listBean.getList().get(1));
    } catch (Exception e) {
        e.printStackTrace();
    }
}

b) ListBean代码

package com.hoo.entity;

import java.util.List;

public class ListBean {
    private String name;
    private List list;
}

c) 生成bind.xml

执行dos命令：

java -cp bin;lib/jibx-tools.jar;lib/log4j-1.2.16.jar org.jibx.binding.BindingGenerator -f bind.xml com.hoo.entity.ListBean

输出：

d) 执行完后会生产bind.xml

Bind文件

<?xml version="1.0" encoding="UTF-8"?>
<binding value-style="attribute">
  <mapping class="com.hoo.entity.ListBean" name="list-bean">
    <value style="element" name="name" field="name" usage="optional"/>
    <collection field="list" usage="optional" factory="org.jibx.runtime.Utility.arrayListFactory"/>
  </mapping>
</binding>

e) 运行Compile工具类

在运行前，一定要将最先前运行的Account那个类的bind.xml文件的内容加入到现在这个bind.xml中，因为ListBean依赖了Account这个类。

命令如下：

java -cp bin;lib/jibx-bind.jar org.jibx.binding.Compile -v bind.xml

运行后你可以看到最后出现这个

f) 运行Test程序，结果如下：

<?xml version="1.0" encoding="UTF-8"?>
<list-bean>
  <account id="1">
    <name>jack</name>
    <email>email</email>
    <address>北京</address>
    <birthday>
      <birthday>2010-11-22</birthday>
    </birthday>
  </account>
  <account id="2">
    <name>tom</name>
    <email>tom@125.com</email>
    <address>china</address>
    <birthday>
      <birthday>2010-11-22</birthday>
    </birthday>
  </account>
</list-bean>
1#jack#email#北京#2010-11-22
2#tom#tom@125.com#china#2010-11-22

3、 转换Java对象数组

a) Test程序

/**
 * <b>function:</b>转换对象数组
 * @author hoojo
 * @createDate 2011-4-26 下午05:32:03
 */
@Test
public void arrayBean2XML() {
    try {
        Account[] acc = new Account[2];
        acc[0] = bean;
        bean = new Account();
        bean.setName("tom");
        bean.setId(223);
        acc[1] = bean;
        AccountArray array = new AccountArray();
        array.setAccounts(acc);


        writer = new StringWriter();
        factory = BindingDirectory.getFactory(AccountArray.class);
        // marshal 编组
        IMarshallingContext mctx = factory.createMarshallingContext();
        mctx.setIndent(2);
        mctx.marshalDocument(array, "UTF-8", null, writer);
        fail(writer);

        reader = new StringReader(writer.toString());
        //unmarshal 解组
        IUnmarshallingContext uctx = factory.createUnmarshallingContext();
        array = (AccountArray) uctx.unmarshalDocument(reader, null);

        fail(array.getAccounts()[0]);
        fail(array.getAccounts()[1]);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

b) AccountArray代码

package com.hoo.entity;

public class AccountArray {
    private Account[] accounts;
    private int size;
    public int getSize() {
        size = accounts.length;
        return size;
    }
    public void setSize(int size) {
        this.size = size;
    }
    public Account[] getAccounts() {
        return accounts;
    }
    public void setAccounts(Account[] accounts) {
        this.accounts = accounts;
    }
}

c) 运行命令生成bind.xml文件

命令如下：

java -cp bin;lib/jibx-tools.jar;lib/log4j-1.2.16.jar org.jibx.binding.BindingGenerator -f bind.xml com.hoo.entity.Account com.hoo.entity.AccountArray

因为AccountArray依赖Account，所以后面带2个类

d) 运行Compile命令

java -cp bin;lib/jibx-bind.jar org.jibx.binding.Compile -v bind.xml

e) 执行完后，就可以运行Test程序了，结果如下

<?xml version="1.0" encoding="UTF-8"?>
<account-array size="0">
  <account id="1">
    <name>jack</name>
    <email>email</email>
    <address>北京</address>
    <birthday>
      <birthday>2010-11-22</birthday>
    </birthday>
  </account>
  <account id="223">
    <name>tom</name>
  </account>
</account-array>
1#jack#email#北京#2010-11-22
223#tom#null#null#null

4、 转换带Map结合的JavaEntity对象

a) Test代码

/**
 * <b>function:</b>转换Map集合
 * @author hoojo
 * @createDate 2011-4-26 下午05:40:34
 */
@Test
public void mapBean2XML() {
    try {
        MapBean mapBean = new MapBean();
        HashMap<String, Account> map = new HashMap<String, Account>();
        map.put("No1", bean);

        bean = new Account();
        bean.setAddress("china");
        bean.setEmail("tom@125.com");
        bean.setId(2);
        bean.setName("tom");
        Birthday day = new Birthday("2010-11-22");
        bean.setBirthday(day);

        map.put("No2", bean);
        mapBean.setMap(map);

        factory = BindingDirectory.getFactory(MapBean.class);
        writer = new StringWriter();
        // marshal 编组
        IMarshallingContext mctx = factory.createMarshallingContext();
        mctx.setIndent(2);
        mctx.marshalDocument(mapBean, "UTF-8", null, writer);
        fail(writer);

        reader = new StringReader(writer.toString());
        //unmarshal 解组
        IUnmarshallingContext uctx = factory.createUnmarshallingContext();
        mapBean = (MapBean) uctx.unmarshalDocument(reader, null);

        fail(mapBean.getMap());
        fail(mapBean.getMap().get("No1"));
        fail(mapBean.getMap().get("No2"));
    } catch (Exception e) {
        e.printStackTrace();
    }
}

b) MapBean代码

package com.hoo.entity;

import java.util.HashMap;

public class MapBean {
    private HashMap<String, Account> map;

    public HashMap<String, Account> getMap() {
        return map;
    }
    public void setMap(HashMap<String, Account> map) {
        this.map = map;
    }
}

c) 生成bind.xml，命令如下

E:\Study\WebHttpUtils>java -cp bin;lib/jibx-tools.jar;lib/log4j-1.2.16.jar org.jibx.binding.BindingGenerator -f bind.xml com.hoo.entity.Account com.hoo.entity.MapBean

运行后，会生产bind.xml；修改bind.xml内容如下：

<?xml version="1.0" encoding="UTF-8"?>
<binding value-style="attribute">
    <mapping class="com.hoo.entity.Account" name="account">
        <value name="id" field="id" />
        <value style="element" name="name" field="name" usage="optional" />
        <value style="element" name="email" field="email" usage="optional" />
        <value style="element" name="address" field="address" usage="optional" />
        <structure field="birthday" usage="optional" name="birthday">
            <value style="element" name="birthday" field="birthday" usage="optional" />
        </structure>
    </mapping>
    <mapping class="com.hoo.entity.MapBean" name="map-bean">
        <structure field="map" usage="optional" name="map"
            marshaller="com.hoo.util.HashMapper" unmarshaller="com.hoo.util.HashMapper">
        </structure>
    </mapping>
</binding>

注意上面的MapBean的structure元素的内容是经过修改的。一定要带上marshaller或unmarshaller，不然无法转换HashMap的。

d) HashMapper代码

package com.hoo.util;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import org.jibx.runtime.IAliasable;
import org.jibx.runtime.IMarshallable;
import org.jibx.runtime.IMarshaller;
import org.jibx.runtime.IMarshallingContext;
import org.jibx.runtime.IUnmarshaller;
import org.jibx.runtime.IUnmarshallingContext;
import org.jibx.runtime.JiBXException;
import org.jibx.runtime.impl.MarshallingContext;
import org.jibx.runtime.impl.UnmarshallingContext;

/**
 * <b>function:</b>http://www.java2s.com/Open-Source/Java/XML/JiBX/tutorial/example21/HashMapper.java.htm
 * @file HashMapper.java
 * @package com.hoo.util
 * @project WebHttpUtils
 * @blog http://blog.csdn.net/IBM_hoojo
 * @email hoojo_@126.com
 * @version 1.0
 */
public class HashMapper implements IMarshaller, IUnmarshaller, IAliasable
{
    private static final String SIZE_ATTRIBUTE_NAME = "size";
    private static final String ENTRY_ELEMENT_NAME = "entry";
    private static final String KEY_ATTRIBUTE_NAME = "key";
    private static final int DEFAULT_SIZE = 10;

    private String m_uri;
    private int m_index;
    private String m_name;

    public HashMapper() {
        m_uri = null;
        m_index = 0;
        m_name = "hashmap";
    }

    public HashMapper(String uri, int index, String name) {
        m_uri = uri;
        m_index = index;
        m_name = name;
    }

    /* (non-Javadoc)
     * @see org.jibx.runtime.IMarshaller#isExtension(int)
     */

    public boolean isExtension(int index) {
        return false;
    }

    /* (non-Javadoc)
     * @see org.jibx.runtime.IMarshaller#marshal(java.lang.Object,
     *  org.jibx.runtime.IMarshallingContext)
     */

    public void marshal(Object obj, IMarshallingContext ictx)
        throws JiBXException {

        // make sure the parameters are as expected
        if (!(obj instanceof HashMap)) {
            throw new JiBXException("Invalid object type for marshaller");
        } else if (!(ictx instanceof MarshallingContext)) {
            throw new JiBXException("Invalid object type for marshaller");
        } else {

            // start by generating start tag for container
            MarshallingContext ctx = (MarshallingContext)ictx;
            HashMap map = (HashMap)obj;
            ctx.startTagAttributes(m_index, m_name).
                attribute(m_index, SIZE_ATTRIBUTE_NAME, map.size()).
                closeStartContent();

            // loop through all entries in hashmap
            Iterator iter = map.entrySet().iterator();
            while (iter.hasNext()) {
                Map.Entry entry = (Map.Entry)iter.next();
                ctx.startTagAttributes(m_index, ENTRY_ELEMENT_NAME);
                if (entry.getKey() != null) {
                    ctx.attribute(m_index, KEY_ATTRIBUTE_NAME,
                        entry.getKey().toString());
                }
                ctx.closeStartContent();
                if (entry.getValue() instanceof IMarshallable) {
                    ((IMarshallable)entry.getValue()).marshal(ctx);
                    ctx.endTag(m_index, ENTRY_ELEMENT_NAME);
                } else {
                    throw new JiBXException("Mapped value is not marshallable");
                }
            }

            // finish with end tag for container element
            ctx.endTag(m_index, m_name);
        }
    }

    /* (non-Javadoc)
     * @see org.jibx.runtime.IUnmarshaller#isPresent(org.jibx.runtime.IUnmarshallingContext)
     */

    public boolean isPresent(IUnmarshallingContext ctx) throws JiBXException {
        return ctx.isAt(m_uri, m_name);
    }

    /* (non-Javadoc)
     * @see org.jibx.runtime.IUnmarshaller#unmarshal(java.lang.Object,
     *  org.jibx.runtime.IUnmarshallingContext)
     */

    public Object unmarshal(Object obj, IUnmarshallingContext ictx)
        throws JiBXException {

        // make sure we're at the appropriate start tag
        UnmarshallingContext ctx = (UnmarshallingContext)ictx;
        if (!ctx.isAt(m_uri, m_name)) {
            ctx.throwStartTagNameError(m_uri, m_name);
        }

        // create new hashmap if needed
        int size = ctx.attributeInt(m_uri, SIZE_ATTRIBUTE_NAME, DEFAULT_SIZE);
        HashMap map = (HashMap)obj;
        if (map == null) {
            map = new HashMap(size);
        }

        // process all entries present in document
        ctx.parsePastStartTag(m_uri, m_name);
        while (ctx.isAt(m_uri, ENTRY_ELEMENT_NAME)) {
            Object key = ctx.attributeText(m_uri, KEY_ATTRIBUTE_NAME, null);
            ctx.parsePastStartTag(m_uri, ENTRY_ELEMENT_NAME);
            Object value = ctx.unmarshalElement();
            map.put(key, value);
            ctx.parsePastEndTag(m_uri, ENTRY_ELEMENT_NAME);
        }
        ctx.parsePastEndTag(m_uri, m_name);
        return map;
    }

    public boolean isExtension(String arg0) {
        return false;
    }
}

e) 然后运行Compile命令

E:\Study\WebHttpUtils>java -cp bin;lib/jibx-bind.jar org.jibx.binding.Compile -v bind.xml

f) 结果如下

<?xml version="1.0" encoding="UTF-8"?>
<map-bean>
  <map size="2">
    <entry key="No2">
      <account id="2">
        <name>tom</name>
        <email>tom@125.com</email>
        <address>china</address>
        <birthday>
          <birthday>2010-11-22</birthday>
        </birthday>
      </account>
    </entry>
    <entry key="No1">
      <account id="1">
        <name>jack</name>
        <email>email</email>
        <address>北京</address>
        <birthday>
          <birthday>2010-11-22</birthday>
        </birthday>
      </account>
    </entry>
  </map>
</map-bean>
{No2=2#tom#tom@125.com#china#2010-11-22, No1=1#jack#email#北京#2010-11-22}
1#jack#email#北京#2010-11-22
2#tom#tom@125.com#china#2010-11-22