对ｘｍｌ文档操作的常用方法

最新推荐文章于 2024-07-26 14:46:50 发布

最新推荐文章于 2024-07-26 14:46:50 发布 · 166 阅读

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本文介绍了一个用于操作XML文档的实用类，提供了加载、保存、查询节点等多种功能，并详细展示了如何使用这些方法来管理和修改XML文件。

java 代码

import java.io.*;
import java.util.*;
import javax.xml.XMLConstants;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Source;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import javax.xml.validation.Validator;
import org.dom4j.*;
import org.dom4j.io.*;
import org.xml.sax.SAXException;
/**
* name：XMLUtil.java
*
* desc: 本类是ｘｍｌ文档操作实用类，提供对ｘｍｌ文档操作的常用方法。
*
*/
public class XMLUtil
{
private Document doc;
/**
* 构造函数
*
*/
public XMLUtil()
{
}
/**
* 方法完成xml文件的加载，在调用本类的其他方法前需要调用loadFromFile()或者loadFromString()
* @param file xml文件对象
* @throws Exception
*/
public void loadFromFile(File file)throws Exception
{
//参数无效
if (file == null || !file.exists() || file.isDirectory())
{
throw new IllegalArgumentException("xml file is not valid!");
}
SAXReader saxReader = new SAXReader();
doc = saxReader.read(file);
}
/**
* 方法完成xml格式字符串的加载，转换成xml文档形式，注意参数必须符合xml格式，
* 否则后续操作会出错
* @param contents xml格式的字符串
* @throws Exception
*/
public void loadFromString(String contents)throws Exception
{
//参数无效
if (contents == null || contents.trim().length() == 0)
{
throw new IllegalArgumentException("argument is not valid!");
}
doc = DocumentHelper.parseText(contents);
}
/**
* 方法执行xml文档的保存
* @param filePath xml文件保存路径
* @param encoding xml文件编码格式（gb2312|utf-8|gbk等）
* @throws IOException
* @throws Exception
*/
public void dump(String filePath, String encoding)throws IOException, Exception
{
//参数无效
if (filePath == null || filePath.trim().length() == 0)
{
throw new IllegalArgumentException("store path is not valid!");
}
encoding = (encoding == null || encoding.trim().length() == 0) ? "gb2312" : encoding;
OutputFormat format = OutputFormat.createPrettyPrint();
format.setEncoding(encoding);
format.setIndent(" ");
FileWriter fileWriter = new FileWriter(filePath);
XMLWriter xmlWriter = new XMLWriter(fileWriter, format);
try
{
xmlWriter.write(doc);
}
catch(Exception e)
{
throw e;
}
finally
{
xmlWriter.close();
xmlWriter = null;
fileWriter.close();
fileWriter = null;
}
}
/**
* 方法获取单个指定节点名的节点
* @param name 节点名,支持Xpath
* @param index 节点出现的索引位置
* @return 找到返回Element,没找到返回null.
* @throws Exception
*/
public Element getElement(String name, int index)throws Exception
{
//节点名无效
if (!isValidate(name))
{
throw new IllegalArgumentException("the element's name is not valid!");
}
//索引位置无效
if (index < 0)
{
throw new IllegalArgumentException("the element's index is not valid!");
}
List elementsList = doc.selectNodes("//" + name);
//指定的节点名存在并且索引有效
if (elementsList != null && elementsList.size() > index)
{
return (Element)elementsList.get(index);
}
return null;
}
/**
* 方法获取指定节点名的节点list
* @param name 节点名
* @return 节点list
* @throws Exception
*/
public ArrayList getElements(String name)throws Exception
{
//节点名无效
if (!isValidate(name))
{
throw new IllegalArgumentException("element name is not valid!");
}
List list = doc.selectNodes("//" + name);
ArrayList <Element>arrayList = new ArrayList<Element>();
//存在节点时，循环获取每一个节点
if (list != null)
{
int length = list.size();
for (int i = 0; i < length; i++)
{
Node node = (Node)list.get(i);
//节点是element实例时，添加到arrayList
if (node instanceof Element)
{
arrayList.add((Element)node);
}
}
}
return arrayList;
}
/**
* 方法获取一个节点的子节点信息
* @param element 节点
* @param subElementName 子节点名称
* @return 子节点list，每个list元素是一个Element
* @throws Exception
*/
public ArrayList getSubElements(Element element, String subElementName)throws Exception
{
//参数无效
if (element == null)
{
throw new IllegalArgumentException("element is null!");
}
//参数无效
if (!isValidate(subElementName))
{
throw new IllegalArgumentException("sub element name is invalid!");
}
return (ArrayList)element.elements(subElementName);
}
/**
* 方法获取单个节点值
* @param name 节点名
* @return 节点值
* @throws Exception
*/
public String getElementValue(String name)throws Exception
{
//invalid argument
if (!isValidate(name))
{
throw new IllegalArgumentException("argument is not valid!");
}
Node node = doc.selectSingleNode("//" + name);
//return the value
if (node instanceof Element)
{
return node.getText().trim();
}
return "";
}
/**
* 方法获取指定节点名的节点值的properties，重复的节点值将过滤掉
* @param name 节点名
* @return 节点值properties
* @throws Exception
*/
public Properties getElementValues(String name)throws Exception
{
if (!isValidate(name))
{
throw new IllegalArgumentException("elememt name is not valid!");
}
List elementList = doc.selectNodes("//" + name);
Properties properties = new Properties();
//节点存在
if (elementList != null && elementList.size() > 0)
{
int length = elementList.size();
for (int i = 0; i < length; i++)
{
String elementValue = ((Element)elementList.get(i)).getTextTrim();
properties.put(elementValue, elementValue);
}
return properties;
}
return properties;
}
/**
* 方法返回指定节点的属性信息
* @param element 节点
* @return 以name,value形式存在的属性
* @throws Exception
*/
public Properties getElementProperties(Element element)throws Exception
{
//参数无效
if (element == null)
{
throw new IllegalArgumentException("element is null!");
}
List attributes = element.attributes();
Properties properties = new Properties();
for (int i = 0; i < attributes.size(); i++)
{
Attribute attr = (Attribute)attributes.get(i);
properties.put(attr.getName(), attr.getValue());
}
return properties;
}
/**
* 方法返回节点的属性信息
* @param elementName 节点名称
* @return 以name,value形式存在的属性
* @throws Exception
*/
public Properties getElementProperties(String elementName)throws Exception
{
//参数无效
if (!isValidate(elementName))
{
throw new IllegalArgumentException("element name is invalid!");
}
return this.getElementProperties(this.getElement(elementName, 0));
}
/**
* 方法执行节点名的更改
* @param oldName 原始节点名
* @param newName 更改后节点名
* @param index 要更改的节点索引（索引指在xml文件中节点出现的位置）
* @throws Exception
*/
public void renameElement(String oldName, String newName, int index)throws Exception
{
//原始节点名无效
if (!isValidate(oldName))
{
throw new IllegalArgumentException("original element name is not valid!");
}
//新的节点名无效
if (!isValidate(newName))
{
throw new IllegalArgumentException("new element name is not valid!");
}
Element element = getElement(oldName, index);
//指定的节点不存在
if (element == null)
{
throw new Exception("can not find element, which name is : " + oldName
+ " index is : " + index);
}
element.setName(newName);
}
/**
* 方法执行节点名的更改
* @param oldName 原始节点名
* @param newName 更改后节点名
* @throws Exception
*/
public void renameElements(String oldName, String newName)throws Exception
{
//原始节点名无效
if (!isValidate(oldName))
{
throw new IllegalArgumentException("original element name is not valid!");
}
//新的节点名无效
if (!isValidate(newName))
{
throw new IllegalArgumentException("new element name is not valid!");
}
ArrayList list = getElements(oldName);
//不存在该节点名
if (list == null)
{
throw new Exception("can not find any element, which name is : " + oldName);
}
//循环更改节点名
int length = list.size();
for (int i = 0; i < length; i++)
{
((Element)list.get(i)).setName(newName);
}
}
/**
* 方法执行子节点的添加，要添加的子节点必须存在父节点，添加子节点的属性可以为空。
* @param parent 父节点名
* @param index 父节点的索引（存在同名父节点时，在第index个父节点处添加子节点）
* @param current 子节点名
* @param currentValue 子节点值
* @param attributes 子节点属性
* @throws Exception
*/
public void addSubElement(String parent, int index, String current, String currentValue,
Properties attributes)throws Exception
{
//父节点无效
if (!isValidate(parent))
{
throw new IllegalArgumentException("parent element is not valid!");
}
//当前节点无效
if (!isValidate(current))
{
throw new IllegalArgumentException("current element is not valid!");
}
Element parentElement = getElement(parent, index);
//指定的父节点不存在
if (parentElement == null)
{
throw new Exception("can not find the specified parent element, which name is :"
+ parent);
}
Element currentElement = parentElement.addElement(current);
//节点值有效
if (currentValue != null && currentValue.length() > 0)
{
currentElement.setText(currentValue);
}
//存在属性时，添加节点属性
if (attributes != null)
{
Enumeration e = attributes.keys();
while (e.hasMoreElements())
{
Object attrName = e.nextElement();
Object attrValue = attributes.get(attrName);
currentElement.addAttribute(attrName.toString(), attrValue.toString());
}
}
}
/**
* 方法执行子节点的添加，要添加的子节点必须存在父节点,
* @param parent 父节点名
* @param index 父节点在xml文档中的索引
* @param childList 子节点list，每个list元素是一个Element
* @throws Exception
*/
public void addSubElements(String parent, int index, ArrayList childList)
throws Exception
{
Element parentElement = getElement(parent, index);
//指定的父节点不存在