IDC资讯中心
包括生成xml文件，增加删除修改节点，增加修改属性等等。
现把我的程序共享，还有我的测试例子，看看大家有什么更好的建议。
其中用到了jdom.jar 和xerces-1.2.2.jar ，都是标准的xml解析包。
可以从网上下载。
/**
* $rcsfile: xmlproperty.java,v $
* $revision: 1.3 $
* $date: 2002/04/02 21:17:09 $
*
* copyright (c) 1999-2001 coolservlets, inc. all rights reserved.
*
* this software is the proprietary information of coolservlets, inc.
* use is subject to license terms.
*/
package crm.bean.common;
import java.io.*;
import java.util.*;
import org.jdom.*;
import org.jdom.input.*;
import org.jdom.output.*;
import org.xml.sax.*;
/**
* provides the the ability to use simple xml property files. each property is
* in the form x.y.z, which would map to an xml snippet of:
* <pre>
* <x>
* <y>
* <z>somevalue</z>
* </y>
* </x>
* </pre>
*
* the xml file is passed in to the constructor and must be readable and
* writtable. setting property values will automatically persist those value
* to disk.
*/
public class xmlproperty {
private string xfile = null;
private file file;
private document doc;
private string pgid="xmlproperty.java";
/**
* parsing the xml file every time we need a property is slow. therefore,
* we use a map to cache property values that are accessed more than once.
*/
private map propertycache = new hashmap();
/**
* creates a new xmlproperty object.
*
* @param file the full path the file that properties should be read from
* and written to.
*/
public xmlproperty(string file)
{
this.file = new file(file);
this.xfile = file;
try
{
saxbuilder builder = new saxbuilder();
doc = builder.build(new file(file));
}
catch (exception e)
{
system.err.println("error creating xml parser in " + pgid);
e.printstacktrace();
}
//
}
public xmlproperty(document doc)
{
this.doc=doc;
}
public document getdocument()
{
return this.doc;
}
/**
* return all children property names of a parent property as a string array,
* or an empty array if the if there are no children. for example, given
* the properties <tt>x.y.a</tt>, <tt>x.y.b</tt>, and <tt>x.y.c</tt>, then
* the child properties of <tt>x.y</tt> are <tt>a</tt>, <tt>b</tt>, and
* <tt>c</tt>.
*
* @param parent the name of the parent property.
* @return all child property values for the given parent.
*/
public string [] getchildrenproperties(string parent) {
string[] propname = parsepropertyname(parent);
// search for this property by traversing down the xml heirarchy.
element element = doc.getrootelement();
for (int i = 0; i < propname.length; i++) {
element = element.getchild(propname[i]);
if (element == null) {
// this node doesnt match this part of the property name which
// indicates this property doesnt exist so return empty array.
return new string [] { };
}
}
// we found matching property, return names of children.
list children = element.getchildren();
int childcount = children.size();
string [] childrennames = new string[childcount];
for (int i=0; i<childcount; i++) {
childrennames[i] = ((element)children.get(i)).getname();
}
return childrennames;
}
//qiuss 2001.11.08
public list getchildren(string name)
{
string[] propname = parsepropertyname(name);
// search for this property by traversing down the xml heirarchy.
element element = doc.getrootelement();
if(propname!=null)
{ // qiuss
for (int i = 0; i < propname.length; i++)
{
element = element.getchild(propname[i]);
if (element == null)
{
// this node doesnt match this part of the property name which
// indicates this property doesnt exist so return null.
return null;
}
}
}
// we found matching property, return names of children.
return(element.getchildren());
}
/**
*@param element element==null start from root
*@param name name==null return this elements value
*@author qiuss
*@date 2001.11.08
*/
public string getproperty(element element,string name)
{
if (propertycache.containskey(name))
{
return (string)propertycache.get(name);
}
string[] propname = parsepropertyname(name);
// search for this property by traversing down the xml heirarchy.
if(element==null) //from rootelement when element equals null
element = doc.getrootelement();
if(propname!=null)
{
for (int i = 0; i < propname.length; i++)
{
element = element.getchild(propname[i]);
if (element == null)
{
// this node doesnt match this part of the property name which
// indicates this property doesnt exist so return null.
return null;
}
}
}
// at this point, we found a matching property, so return its value.
// empty strings are returned as null.
string value = element.gettext();
if ("".equals(value)) {
return null;
}
else {
value = value.trim();
propertycache.put(name, value);
return value;
}
}
/**
* returns the value of the specified property.
* @param name the name of the property to get.
* @return the value of the specified property.
*/
public string getproperty(string name)
{
return getproperty(null,name);
}
/**
*@param element element==null start from root
*@param name childs element name eg. x.y.z
*@param attname attribute name eg. "abc=1234" if attname==null get first element
*@return searched element
*@author qiuss
*@date 2001.11.08
*/
public element getchild(element element,string name,string attname)
{
//if(name==null) return element;
string[] propname = parsepropertyname(name);
string[] attrname = parseattributename(attname);
// search for this property by traversing down the xml heirarchy.
if(element==null)
element = doc.getrootelement();
if(propname!=null)
{
// qiuss
for (int i = 0; i < propname.length; i++)
{
element = element.getchild(propname[i]);
if (element == null)
{
// this node doesnt match this part of the property name which
// indicates this property doesnt exist so return null.
return null;
}
}
}
// we found matching property, return names of children.
list elist=element.getchildren();
if(attrname==null)
return (element)elist.get(0);
iterator it=elist.iterator();
while(it.hasnext()){
attribute att;
element ele=(element)it.next();
if((att=ele.getattribute(attrname[0]))!=null)
{
if(att.getvalue().equals(attrname[1]))
return ele;
}
}
return null;
}
/**
* 设置一个元素值。如果指定的元素不存在，就自动创建该元素。
*
* @param name 需要赋值的元素名称，格式为 x.y.z
* @param value 元素值
*
* @throws ioexception
*/
public void setproperty(string name, string value)
{
propertycache.put(name, value);
//查找指定的元素元素
element element = this.findcreate(name);
element.settext(value);
saveproperties();
}
/**
* 设置一个元素的attribute值。如果指定的元素不存在，就自动创建该元素。
*
* @param name 需要赋值的元素名称，格式为 x.y.z
* @param attr attribute名称
* @param value 元素值
*
* @throws ioexception
*/
public void setproperty(string name, string attr, string value)
{
string nameattr = name + ":" + attr;
propertycache.put(nameattr, value);
//查找指定的元素元素
element element = this.findcreate(name);
element.setattribute(attr, value);
saveproperties();
}
/**
* helper方法，查找一个指定的元素,如果这个元素不存在，创建它
*
* @param name 元素名称，格式为 x.y.z
* @return element 找到就返回这个元素，否则返回创建的新元素
*/
private element findcreate(string name)
{
//分解元素的名称
string[] propname = parsepropertyname(name);
element element = doc.getrootelement();
//遍历搜索匹配的元素，不存在则创建它
for (int i = 0; i < propname.length; i++)
{
if(element.getchild(propname[i]) == null)
{
//自动创建该元素
element.addcontent(new element(propname[i]));
}
element = element.getchild(propname[i]);
}
//找到啦！
return element;
}
/**
* 删除指定的元素，如果该元素不存在，不做任何事情
*
* @param name 要删除的元素的名称，格式为 x.y.z
*
*/
public void deleteproperty(string name)
{
if(propertycache.containskey(name))
propertycache.remove(name);
element element = this.findonly(name);
if(element != null) element.detach();
saveproperties();
}
/**
* 删除指定的元素的attribute，如果该元素或者attribute不存在，不做任何事情
*
* @param name 元素的名称，格式为 x.y.z
* @param attr attribute的名称
*
* @throws ioexception
*/
public void deleteproperty(string name, string attr) throws ioexception
{
string nameattr = name + ":" + attr;
if(propertycache.containskey(nameattr))
propertycache.remove(nameattr);
element element = this.findonly(name);
if(element != null) element.removeattribute(attr);
saveproperties();
}
