`
helloyesyes
  • 浏览: 1273325 次
  • 性别: Icon_minigender_2
  • 来自: 武汉
文章分类
社区版块
存档分类
最新评论

使用Dom4j操作XML

 
阅读更多

Dom4j也可以很方便完成XML文档的创建、元素的修改、文档的查询遍历等,但dom4j稍比jdom复杂一点,不过在大片文档的情况下dom4j的性能要不jdom好。

 

# 准备

首先,提供相关的jar包

Dom4j jar包下载:

http://sourceforge.net/projects/dom4j/files/dom4j-2.0.0-ALPHA-2/

jaxen jar下载:

http://repo1.maven.org/maven2/jaxen/jaxen/1.1.1/jaxen-1.1.1.jar

和dom4j依赖或相关的jar:

http://dom4j.sourceforge.net/dependencies.html

Junit-jar下载:

http://ebr.springsource.com/repository/app/bundle/version/download?name=com.springsource.org.junit&version=4.8.1&type=binary

其次,准备测试案例的部分代码:

package
 com.hoo.test;
 
import
 java.io.File;
import
 java.util.Iterator;
import
 java.util.List;
import
 org.dom4j.Attribute;
import
 org.dom4j.Document;
import
 org.dom4j.DocumentException;
import
 org.dom4j.DocumentHelper;
import
 org.dom4j.Element;
import
 org.dom4j.Node;
import
 org.dom4j.QName;
import
 org.dom4j.dom.DOMAttribute;
import
 org.dom4j.io.SAXReader;
import
 org.dom4j.tree.BaseElement;
import
 org.junit.After;
import
 org.junit.Before;
import
 org.junit.Test;
 
/**
 * <b>function:</b> 使用Dom4j操作XML
 * @author hoojo
 * @createDate 2011-8-5 下午06:15:40
 * @file DocumentTest.java
 * @package com.hoo.test
 * @project Dom4jTest
 * @blog http://blog.csdn.net/IBM_hoojo
 * @email hoojo_@126.com
 * @version 1.0
 */
public
 class
 DocumentTest {
    
    private
 SAXReader reader = null;
    
    @Before
    public
 void
 init() {
        reader = new
 SAXReader();
    }
    
    @After
    public
 void
 destory() {
        reader = null;
        System.gc();
    }
    
    public
 void
 fail(Object o) {
        if
 (o != null)
            System.out.println(o);
    }
}

# 创建一篇 XML 文档

文档格式如下:

<?
xml
 version
="1.0"
 encoding
="UTF-8"
?>
 
<
catalog
>
 
    <!--An XML Catalog-->
 
    <?
target
 instruction
?>
    <
journal
 title
="XML Zone"
 publisher
="IBM developerWorks"
>
 
         <
article
 level
="Intermediate"
 date
="December-2001"
>
             <
title
>
Java configuration with XML Schema</
title
>
 
             <
author
>
 
                 <
firstname
>
Marcello</
firstname
>
 
                 <
lastname
>
Vitaletti</
lastname
>
 
             </
author
>
           </
article
>
    </
journal
>
 
</
catalog
>

 

创建文档代码如下:

/**
 * <b>function:</b>创建文档
 * @author hoojo
 * @createDate 2011-8-5 下午06:18:18
 */
@Test
public
 void
 createDocument() {
    //创建一篇文档
    Document doc = DocumentHelper.createDocument();
    
    //添加一个元素
    Element root = doc.addElement("catalog"
);
    //为root元素添加注释
    root.addComment("An XML Catalog"
);
    //添加标记
    root.addProcessingInstruction("target"
, "instruction"
);
    
    //创建元素
    Element journalEl = new
 BaseElement("journal"
);
    //添加属性
    journalEl.addAttribute("title"
, "XML Zone"
);
    journalEl.addAttribute("publisher"
, "IBM developerWorks"
);
    root.add(journalEl);
    
    //添加元素
    Element articleEl = journalEl.addElement("article"
);
    articleEl.addAttribute("level"
, "Intermediate"
);
    articleEl.addAttribute("date"
, "December-2001"
);
    
    Element titleEl = articleEl.addElement("title"
);
    //设置文本内容
    titleEl.setText("Java configuration with XML Schema"
);
    //titleEl.addText("Java configuration with XML Schema");
    
    Element authorEl = articleEl.addElement("author"
);
    authorEl.addElement("firstname"
).setText("Marcello"
);
    authorEl.addElement("lastname"
).addText("Vitaletti"
);
    
    //可以使用 addDocType() 方法添加文档类型说明。 
    doc.addDocType("catalog"
, null,"file://c:/Dtds/catalog.dtd"
); 
 
    fail(doc.getRootElement().getName());
    
    //将xml转换成文本
    fail(doc.asXML());
    
    //写入到文件
    /*XMLWriter output;
    try {
        output = new XMLWriter(new FileWriter(new File("file/catalog.xml")));
        output.write(doc);
        output.close();
    } catch (IOException e) {
        e.printStackTrace();
    }*/
}

* DocumentHelper是一个文档助手类(工具类),它可以完成文档、元素、文本、属性、注释、CDATA、Namespace、XPath的创建,以及利用XPath完成文档的遍历和将文本转换成Document;

parseText完成将xml字符串转换成Doc的功能

Document doc = DocumentHelper.parseText("<root></root>"
);

createDocument创建一个文档

Document doc = DocumentHelper.createDocument();

如果带参数就会创建一个带有根元素的文档

createElement创建一个元素

Element el = DocumentHelper.createElement("el"
);

* Document的addElement方法可以给当前文档添加一个子元素

Element root = doc.addElement("catalog"
);

* addComment方法可以添加一段注释

root.addComment("An XML Catalog"
);

为root元素添加一段注释

* addProcessingInstruction添加一个标记

root.addProcessingInstruction("target"
, "instruction"
);

为root元素添加一个标记

* new BaseElement可以创建一个元素

Element journalEl = new
 BaseElement("journal"
);

* addAttribute添加属性

journalEl.addAttribute("title"
, "XML Zone"
);

* add添加一个元素

root.add(journalEl);

将journalEl元素添加到root元素中

 

* addElement添加一个元素,并返回当前元素

Element articleEl = journalEl.addElement("article"
);

给journalEl元素添加一个子元素article

* setText、addText可以设置元素的文本

authorEl.addElement("firstname"
).setText("Marcello"
);
authorEl.addElement("lastname"
).addText("Vitaletti"
);

* addDocType可以设置文档的DOCTYPE

doc.addDocType("catalog"
, null,file://c:/Dtds/catalog.dtd);

* asXML可以将文档或元素转换成一段xml字符串

doc.asXML();
root.asXML();

* XMLWriter类可以把文档写入到文件中

output = new
 XMLWriter(new
 FileWriter(new
 File("file/catalog.xml"
)));
output.write(doc);
output.close();

# 修改 XML 文档内容

/**
 * <b>function:</b> 修改XML内容
 * @author hoojo
 * @createDate 2011-8-9 下午03:37:04
 */
@SuppressWarnings("unchecked"
)
@Test
public
 void
 modifyDoc() {
    try
 {
        Document doc = reader.read(new
 File("file/catalog.xml"
));
        
        //修改属性内容
        List list = doc.selectNodes("//article/@level"
);
        Iterator<Attribute> iter = list.iterator();
        while
 (iter.hasNext()) {
            Attribute attr = iter.next();
            fail(attr.getName() + "#"
 + attr.getValue() + "#"
 + attr.getText());
            if
 ("Intermediate"
.equals(attr.getValue())) {
                //修改属性值
                attr.setValue("Introductory"
);
                fail(attr.getName() + "#"
 + attr.getValue() + "#"
 + attr.getText());
            }
        }
        
        list = doc.selectNodes("//article/@date"
);
        iter = list.iterator();
        while
 (iter.hasNext()) {
            Attribute attr = iter.next();
            fail(attr.getName() + "#"
 + attr.getValue() + "#"
 + attr.getText());
            if
 ("December-2001"
.equals(attr.getValue())) {
                //修改属性值
                attr.setValue("December-2011"
);
                fail(attr.getName() + "#"
 + attr.getValue() + "#"
 + attr.getText());
            }
        }
        
        //修改节点内容
        list = doc.selectNodes("//article"
);
        Iterator<Element> it = list.iterator();
        while
 (it.hasNext()) {
            Element el = it.next();
            fail(el.getName() + "#"
 + el.getText() + "#"
 + el.getStringValue());
            //修改title元素
            Iterator<Element> elIter = el.elementIterator("title"
);
            while
(elIter.hasNext()) {
                Element titleEl = elIter.next();
                fail(titleEl.getName() + "#"
 + titleEl.getText() + "#"
 + titleEl.getStringValue());
                if
 ("Java configuration with XML Schema"
.equals(titleEl.getTextTrim())) {
                    //修改元素文本值
                    titleEl.setText("Modify the Java configuration with XML Schema"
);
                    fail(titleEl.getName() + "#"
 + titleEl.getText() + "#"
 + titleEl.getStringValue());
                }
            }
        }
        
        //修改节点子元素内容
        list = doc.selectNodes("//article/author"
);
        it = list.iterator();
        while
 (it.hasNext()) {
            Element el = it.next();
            fail(el.getName() + "#"
 + el.getText() + "#"
 + el.getStringValue());
            List<Element> childs = el.elements();
            for
 (Element e : childs) {
                fail(e.getName() + "#"
 + e.getText() + "#"
 + e.getStringValue());
                if
 ("Marcello"
.equals(e.getTextTrim())) {
                    e.setText("Ayesha"
);
                } else
 if
 ("Vitaletti"
.equals(e.getTextTrim())) {
                    e.setText("Malik"
);
                } 
                fail(e.getName() + "#"
 + e.getText() + "#"
 + e.getStringValue());
            }
        }
        
        //写入到文件
        /*XMLWriter output = new XMLWriter(new FileWriter(new File("file/catalog-modified.xml")));
        output.write(doc);
        output.close();*/
    } catch
 (DocumentException e) {
        e.printStackTrace();
    } catch
 (Exception e) {
        e.printStackTrace();
    }
}

* reader.read(new File("file/catalog.xml"));读取指定xml文件内容到文档中;

* selectNodes是XPath的查询方法,完成xml文档的查询,传递xpath路径。其使用方法可以参考jdom的xpath的使用方法:

     http://www.cnblogs.com/hoojo/archive/2011/08/11/2134638.html

* getName获取元素标签名称、getValue、getText获取值、文本内容;

* elementIterator("title");获取当前节点下所有的title元素,返回Iterator;

* elements获取下面所有的子元素,返回的是一个集合List;

 

 

# 显示文档相关信息

private
 String format(int
 i) {
    String temp = ""
;
    while
 (i > 0) {
        temp += "--"
;
        i--;
    }
    return
 temp;
}
 
/**
 * <b>function:</b>递归显示文档内容
 * @author hoojo
 * @createDate 2011-8-9 下午03:43:45
 * @param i
 * @param els
 */
private
 void
 print(int
 i, List<Element> els) {
    i++;
    for
 (Element el : els) {
        fail(format(i) + "##"
 + el.getName() + "#"
 + el.getTextTrim());
        if
 (el.hasContent()) {
            print(i, el.elements());
        } 
    }
}
 
/**
 * <b>function:</b>显示文档相关信息
 * @author hoojo
 * @createDate 2011-8-9 下午03:44:10
 */
@Test
public
 void
 printInfo() {
    try
 {
        Document doc = reader.read(new
 File("file/catalog.xml"
));
        fail("asXML: "
 + doc.asXML());
        
        fail(doc.asXPathResult(new
 BaseElement("article"
)));
        List<Node> list = doc.content();
        for
 (Node node : list) {
            fail("Node: "
 + node.getName() + "#"
 + node.getText() + "#"
 + node.getStringValue());
        }
        
        fail("-----------------------------"
);
        print(0, doc.getRootElement().elements());
        
        fail("getDocType: "
 + doc.getDocType());
        fail("getNodeTypeName: "
 + doc.getNodeTypeName());
        fail("getPath: "
 + doc.getRootElement().getPath());
        fail("getPath: "
 + doc.getRootElement().getPath(new
 BaseElement("journal"
)));
        fail("getUniquePath: "
 + doc.getRootElement().getUniquePath());
        fail("getXMLEncoding: "
 + doc.getXMLEncoding());
        fail("hasContent: "
 + doc.hasContent());
        fail("isReadOnly: "
 + doc.isReadOnly());
        fail("nodeCount: "
 + doc.nodeCount());
        fail("supportsParent: "
 + doc.supportsParent());
    } catch
 (DocumentException e) {
        e.printStackTrace();
    }
    fail("getEncoding: "
 + reader.getEncoding());
    fail("isIgnoreComments: "
 + reader.isIgnoreComments());
    fail("isMergeAdjacentText: "
 + reader.isMergeAdjacentText());
    fail("isStringInternEnabled: "
 + reader.isStringInternEnabled());
    fail("isStripWhitespaceText: "
 + reader.isStripWhitespaceText());
    fail("isValidating: "
 + reader.isValidating());
}

 

# 删除文档内容

/**
 * <b>function:</b> 删除节点内容
 * @author hoojo
 * @createDate 2011-8-9 下午03:47:44
 */
@Test
public
 void
 removeNode() {
    try
 {
        Document doc = reader.read(new
 File("file/catalog-modified.xml"
));
        fail("comment: "
 + doc.selectSingleNode("//comment()"
));
        //删除注释
        doc.getRootElement().remove(doc.selectSingleNode("//comment()"
));
        
        Element node = (Element) doc.selectSingleNode("//article"
);
        //删除属性
        node.remove(new
 DOMAttribute(QName.get("level"
), "Introductory"
));
        //删除元素 节点
        node.remove(doc.selectSingleNode("//title"
));
        
        //只能删除下一级节点,不能超过一级;(需要在父元素的节点上删除子元素)
        Node lastNameNode = node.selectSingleNode("//lastname"
);
        lastNameNode.getParent().remove(lastNameNode);
        
        fail("Text: "
 + doc.selectObject("//*[text()='Ayesha']"
));
        Element firstNameEl = (Element)doc.selectObject("//firstname"
);
        fail("Text: "
 + firstNameEl.selectSingleNode("text()"
));
        
        //删除text文本
        //firstNameEl.remove(firstNameEl.selectSingleNode("text()"));
        //firstNameEl.remove(doc.selectSingleNode("//firstname/text()"));
        firstNameEl.remove(doc.selectSingleNode("//*[text()='Ayesha']/text()"
));
        
        //删除子元素author
        //node.remove(node.selectSingleNode("//author"));
        
        fail(doc.asXML());
    } catch
 (Exception e) {
        e.printStackTrace();
    }
}

* 删除注释

doc.getRootElement().remove(doc.selectSingleNode("//comment()"
));

删除root元素下面的注释

* 删除属性

node.remove(new
 DOMAttribute(QName.get("level"
), "Introductory"
));

删除node节点中的名称为level,其值为Introductory的属性

* 删除元素

node.remove(doc.selectSingleNode("//title"
));

删除node节点下的title元素

* 删除文本

firstNameEl.remove(firstNameEl.selectSingleNode("text()"
));
firstNameEl.remove(doc.selectSingleNode("//firstname/text()"
));
firstNameEl.remove(doc.selectSingleNode("//*[text()='Ayesha']/text()"
));

删除firstNameEl的文本内容

 

0
1
分享到:
评论

相关推荐

Global site tag (gtag.js) - Google Analytics